MULTI-HAZARD MITIGATION PLAN FOR BENTON COUNTY, OREGON January 2006 Prepared by: Kenneth A. Goettel Goettel & Associates Inc. 1732 Arena Drive Davis, CA 95616 (530) 750-0440 www.kengoettel.com Cover Photos: Top: Highway 34 landslide debris, December 1998 Left: Flooding in vicinity of Highway 34, December 1998 Right: Flooding on Quarry Road, North Albany, February 1996 This document is a result of several partnerships that collaborated during the research and creation of this plan. Marion, Polk, Yamhill Counties: J. Ingram Moore Benton County: M. Bamberger Lane County: L. Cook, M. McKay Linn County: R. Wheeldon City of Albany: D. Tedisch This Natural Hazard Mitigation Plan was developed through a regional partnership funded by the Federal Emergency Management Agency's Pre-Disaster Mitigation Competitive Grant Program. The Mid/Southern Willamette Valley Region grant was awarded to support the development of natural hazard mitigation plans for the region. The region's planning process utilized a seven-step planning process, plan framework, and plan development support provided by the Oregon Natural Hazards Workgroup at the University of Oregon. Regional partners include: ? Federal Emergency Management Agency Region 10 ? Marion County ? Oregon Emergency Management ? Polk County ? Oregon Department of Geology and Mineral Industries ? Yamhill County ? Oregon Natural Hazard Workgroup at the University of Oregon's ? City of Albany ? Community Service Center ? Mid-Willamette Valley Council of Governments ? Benton County ? City of Corvallis ? Lane County ? City of Philomath ? Linn County ? Oregon State University Exec - 1 EXECUTIVE SUMMARY This Multi-Hazard Mitigation Plan for Benton County, Oregon covers each of the major natural and human-caused hazards that pose risks to the County. The primary objectives of this Mitigation plan are to reduce the negative impacts of future disasters on the community: to enhance life safety, increase public awareness, protect natural systems, and build partnerships. This Mitigation Plan is a planning document, not a regulatory document. This mitigation plan meets FEMA?s planning requirements by addressing hazards, vulnerability and risk. Hazard means the frequency and severity of disaster events. Vulnerability means the value, importance, and fragility of buildings and infrastructure. Risk means the threat to people, buildings and infrastructure, taking into account the probabilities of disaster events. Adoption of a mitigation plan is required for communities to remain eligible for future FEMA mitigation grant funds. Review comments, suggestions, corrections and additions are enthusiastically encouraged from all interested parties. Please send comments to: Mike Bamberger, Benton County Emergency Manager at: Michael.Bamberger@co.benton.or.us Overview and Context Chapter 1: Introduction Chapter 2: Community Profile Chapter 3: Community Involvement and Public Process Chapter 4: Mitigation Goals, Strategies and Action Items Chapter 5: Plan Adoption, Implementation, and Maintenance Hazards Chapter 6: Floods Chapter 7: Winter Storms Chapter 8: Landslides Chapter 9: Wildland/Urban Interface Fires Chapter 10: Earthquakes Chapter 11: Volcanic Hazards Chapter 12: Dam Safety Chapter 13: Disruption of Utility and Transportation Systems Chapter 14: HAZMAT Incidents Chapter 15: Terrorism Appendices A - Natural Hazards Resource Directory B - Benton County Special Districts Exec - 2 Mission Statement The mission of the Benton County Hazard Mitigation Plan is to: Promote sound polices and programs designed to protect citizens, critical facilities, infrastructure, public and private property, economic vitality, and the environment from natural and human- caused hazards. 4.3 Mitigation Plan Goals and Objectives Goal 1: Reduce the Threat to Life Safety Objectives: ? Enhance life safety by minimizing the potential for deaths and injuries in future disaster events. ? Improve community warning and notification methods ? Evaluate jurisdictional guidelines, codes, policies, and permitting processes to address hazard mitigation Goal 2: Protect Critical Facilities and Enhance Emergency and Essential Services Objectives: ? Implement activities or projects to protect critical facilities and infrastructure ? Seek opportunities to enhance, protect, and integrate emergency and essential services. ? Strengthen emergency operations plans and procedures by increasing collaboration and coordination among public agencies, non-profit organizations, business, and industry. Goal 3: Reduce the Threat to Property Objectives: ? Seek opportunities to protect, enhance and integrate emergency and essential services with land use planning and natural resource management. ? Strengthen emergency operations plans and procedures by increasing collaboration and coordination among public agencies, non-profit organizations, business, industry and the citizens of Benton County. ? Preserve and rehabilitate natural systems to serve as natural hazard mitigation functions (i.e., floodplains, watersheds, and urban interfaces) Exec - 3 Goal 4: Create a Disaster Resistant and Disaster-Resilient Economy Objectives: ? Develop and implement activities to protect economic well-being and vitality while reducing economic hardship in post disaster situations. ? Reduce insurance losses and repetitive claims for chronic hazard events ? Work with State and Federal Partners to reduce short-term and long-term recovery and reconstruction costs. ? Work with local organization, such as Benton Emergency Planning Association (BEPA). ? Expedite pre-disaster and post-disaster grants and program funding. Goal 5: Increase Public Awareness, Education, Outreach, and Partnerships Objectives: ? Coordinate and collaborate, where possible, risk reduction outreach efforts with the Oregon Partners for Disaster Resistance & Resilience and other public and private organizations. ? Develop and implement risk reduction education programs to increase awareness among citizens, local, county, and regional agencies, non- profit organizations, business, and industry. ? Promote insurance coverage for catastrophic hazards ? Strengthen communication and coordinate participation in and between public agencies, citizens, nonprofit organizations, business, and industry. ? Develop relationships for planning and mitigation activities that are inclusive of multiple areas (i.e., communication and environment and transportation) Exec - 4 Exec - 5 Mitigation Plan Goals Addressed Hazard Action Item Coordinating Organizations Timeline Life Safe Critical Facilities and Eme Services Protect Property Disaster Resilient Econo Public Education, Outr Partner Multi-Hazard Mitigation Action Items Short-Term #1 Establish a formal role for the Benton County Hazard Steering Planning Committee to develop a sustainable process to encourage, implement, monitor, and evaluate countywide mitigation actionsBenton County Hazard Mitigation Steering Committee Ongoing X X X X X Short-Term #2 Identify and pursue funding opportunities to implement mitigation actions Benton County Hazard Mitigation Steering Committee Ongoing X X X X X Short-Term #3 Develop public and private sector partnerships to foster hazard mitigation activities, Benton County Hazard Mitigation Steering Committee Ongoing X X X X X Short-Term #4 Develop detailed inventories of at-risk buildings and infrastructure and prioritize mitigation actions, especially for critical facilities Benton County GIS and Emergency Management 1-2 YearsX X X X Long-Term #1 Develop education programs aimed at mitigating the risk posed by hazards Benton County Hazard Mitigation Steering Committee, BC Em Mgt Council Ongoing X X X X X Long-Term #2 Integrate the Mitigation Plan findings into planning and regulatory documents and programs Benton County Hazard Mitigation Steering Committee and Community Development, cities Ongoing X X X X X Long-Term #3 Integrate hazard, vulnerability and risk Mitigation Plan findings into enhanced Emergency Operations planning. Benton County Emergency Management Ongoing X X X X X Long-Term #4 Countywide GIS mapping: add data layers for high risk areas for each natural hazard Benton County GIS and Emergency Management, cities Ongoing X X X X X Exec - 6 Mitigation Plan Goals Addressed Hazard Action Item Coordinating Organizations Timeline Life Safe Critical Facilities and Eme Services Protect Property Disaster Resilient Econo Public Education, Outr Partner Flood Mitigation Action Items: Within FEMA-Mapped Floodplains Short-Term #1 Complete inventory of critical facilities within 100- year and 500-year floodplains, with GIS mapping if possible Benton County GIS, cities, special districts Ongoing X X X X Short-Term #2 Complete inventory of residential and commercial buildings within 100-year and 500-year floodplains, with GIS mapping if possible Benton County GIS, cities, special districts Ongoing X X X Short-Term #3 Consult with property owners and explore mitigation actions for any Benton County properties on FEMA's national repetitive loss list Benton County Hazard Mitigation Steering Committee / Community Development / BC Emer Mgt 1 year X X X X Long-Term #1 Survey elevation data for critical facilities, residential buildings and commercial buildings within the 100-year floodplain and establish flood mitigation priorities Local emergency service agencies, Benton County Hazard Mitigation Steering Committee 2-5 years X X X X X Long-Term #2 For critical facilities within the 100-year floodplain and for other structures deep within the 100-year floodplain explore mitigation options with property owners and implement mitigation measures Local emergency service agencies, Benton County Hazard Mitigation Steering Committee 2-10 yearsX X X X X Exec - 7 Mitigation Plan Goals Addressed Hazard Action Item Coordinating Organizations Timeline Life Safe Critical Facilities and Eme Services Protect Property Disaster Resilient Econo Public Education, Outr Partner Flood Mitigation Action Items: Outside of FEMA-Mapped Floodplains Short-Term #1 Complete the inventory of locations in Benton County subject to frequent storm water flooding Benton County Roads and GIS, cities, special districts Ongoing XX X X X Long-Term #1 For locations with repetitive flooding and significant damages or road closures, determine and implement mitigation measures such as upsizing culverts or storm water drainage ditches Benton County Engineer, Community Development, cities, special districts Ongoing XX X X X Exec - 8 Mitigation Plan Goals Addressed Hazard Action Item Coordinating Organizations Timeline Life Safe Critical Facilities and Eme Services Protect Property Disaster Resilient Econo Public Education, Outr Partner Winter Storms Mitigation Action Items Short-Term #1 Complete the inventory of locations in Benton County subject to frequent storm water flooding Benton County Roads, GIS, cities Ongoing X X X X X Short-Term #2 Enhance tree trimming efforts especially for transmission lines and trunk distribution lines. BPA, Consumers Power, PP&L, local PUDs Ongoing X X X X X Short-Term #3 Encourage prudent tree planting (avoid service lines) and safe, professional tree trimming where necessary Community Development Ongoing X X X Short-Term #4 Ensure that all critical facilities in Benton County have backup power and emergency operations plans to deal with power outages Emergency Management, Benton County Facilities, Benton County Hazard Mitigation Steering Committee 1-2 YearsX X Long-Term #1 For locations with repetitive flooding and significant damages or road closures, determine and implement mitigation measures such as upsizing culverts or storm water drainage ditches Benton County Roads and Engineer, cities Ongoing X X X X X Long-Term #2 Consider upgrading lines and poles to improve wind/ice loading, under grounding critical lines, and adding interconnect switches to allow alternative feed paths and disconnect switches to minimize outage areas BPA, Consumers Power, PP&L, local PUDs 5 Years X X X X X Long-Term #3 Encourage new developments to include underground power lines Benton County Community Development, cities ongoing X X X X X Exec - 9 Mitigation Plan Goals Addressed Hazard Action Item Coordinating Organizations Timeline Life Safe Critical Facilities and Emergen Serv Protect Property Disaster Resilient Econo Public Education, Outr Partner Landslide Mitigation Action Items Short-Term #1 Complete the inventory of locations where critical facilities, other buildings and infrastructure are subject to landslides Benton County GIS, cities (public works) 1-2 YearsX X X X X Long-Term #1 Consider landslide mitigation actions for slides seriously threatening critical facilities, other buildings or infrastructure Benton County Engineer, Community Development, cities, special districts 5 Years X X X X X Long-Term #2 Limit future development in high landslide potential areas by adopting landslide development practices that minimize landslide potential Benton County Community Development Ongoing X X X X X Exec - 10 Mitigation Plan Goals Addressed Hazard Action Item Coordinating Organizations Timeline Life Safe Critical Facilities and Emergen Serv Protect Property Disaster Resilient Econo Public Education, Outr Partner Wildland/Urban Interface Fire Mitigation Action Items Short-Term #1 Identify specific parts of Benton County at high risk for urban/wildland urban interface fires because of fuel loading, topography and prevailing construction practices Benton County GIS and Community Development, Benton County Fire Defense Board, fire agencies 1-2 YearsX X X X X Short-Term #2 Identify evacuation routes and procedures for high risk areas and educate the public Benton County Fire Defense Board, fire agencies, law enforcement, County Roads, public works Ongoing X X X X Short-Term #3 Develop Community Wildland Fire Protection Plans Benton County Community Development, cities, fire agencies, ODF 1-2 YearsX X X X X Short-Term #4 Collect statistics on non-ODF vegetation fires from local fire agencies Benton County Fire Defense Board, GIS 1 year X X X X Short-Term #5 Complete surveys of areas of special concern for Wildland/urban interface firs from remaining l fire agencies in Benton County along the lines of Table 9.5 above Local Fire Departments, Benton County Emergency Services 1 year X X X X Long-Term #1 Encourage fire-safe construction practices for existing and new construction in high risk areas Benton County Community Development, city building departments, fire agencies Ongoing X X X X X Exec - 11 Mitigation Plan Goals Addressed Hazard Action Item Coordinating Organizations Timeline Life Safe Critical Facilities and Eme Services Protect Property Disaster Resilient Econo Public Education, Outr Partner Earthquake Mitigation Action Items Short-Term #1 Complete inventory of public and commercial buildings that may be particularly vulnerable to earthquake damage Benton County GIS, Community Development, cities, special districts 1-2 YearsX X X X X Short-Term #2 Complete inventory of wood-frame residential buildings that may be particularly vulnerable to earthquake damage, including pre-1940s homes and homes with cripple wall foundations. Benton County GIS, Community Development, cities, special districts 1-2 YearsX X X X X Short-Term #3 Disseminate FEMA pamphlets to educate homeowners about structural and non-structural retrofitting of vulnerable homes and encourage retrofit Benton County Community Development, Emergency Management, Hazard Mitigation Steering Committee Ongoing X X X X Short-Term #4 Complete seismic vulnerability analysis of important public facilities with significant seismic vulnerabilities County, cities, special districts 1-2 YearsX X X X X Long-Term #1 Obtain funding and retrofit important public facilities with significant seismic vulnerabilities County, cities, special districts 10 years X X X X X Long-Term #2 Retrofit bridges that are not seismically adequate for lifeline transportation routes ODOT, County, cities, roads X X X X X Exec - 12 Mitigation Plan Goals Addressed Hazard Action Item Coordinating Organizations Timeline Life Safe Critical Facilities and Eme Services Protect Property Disaster Resilient Econo Public Education, Outr Partner Volcanic Hazards Mitigation Action Items Short-Term #1 Update public emergency notification procedures for ash fall events CRCC, Benton County Emergency Management 1-2 YearsX X X Short-Term #2 Update emergency response planning for ash fall events local emergency services agencies 1-2 YearsX X X Short-Term #3 Evaluate capability of water treatment plants to deal with high turbidity from ash falls and upgrade treatment facilities and emergency response plans to deal with ash falls local water agencies 1-2 YearsX X X X X Short-Term #4 Evaluate ash impact on storm water drainage system and develop mitigation actions if necessary public works agencies 1-2 Years X X X X Exec - 13 Mitigation Plan Goals Addressed Hazard Action Item Coordinating Organizations Timeline Life Safe Critical Facilities and Emerg Protect Property Disaster Resilient Econo Public Education, Outr Partner Dam Safety Mitigation Action Items Short-Term #1 Prepare high resolution maps of dam failure inundation areas and update emergency response plans, including public notification and evacuation routes Benton County GIS, Benton County Emergency Management, Corps of Engineers, city building departments 1-2 YearsX X X Short-Term #2 Identify dikes and owners and the impact of protected structures Benton County GIS, Benton County Emergency Management, Benton County Public Works, city building departments 2-3 years X X X X Long-Term #2 Encourage the Corps of Engineers to complete seismic vulnerability assessments for dams upstream of heavily populated areas in Benton County and to make seismic improvements as necessary Benton County Hazard Mitigation Steering Committee, US Army Corps of Engineers Ongoing X X X X X Long-Term #3 Evaluate the adequacy of dike systems for both floods and earthquakes and implement mitigation measures if necessary Benton County Public Works, US Army Corps of Engineers Ongoing X X X X X Exec - 14 Mitigation Plan Goals Addressed Hazard Action Item Coordinating Organizations Timeline Life Safe Critical Facilities and Eme Services Protect Property Disaster Resilient Econo Public Education, Outr Partner Utility and Transportation System Disruption Mitigation Action Items Short-Term #1 Educate and encourage residents to maintain several days of emergency supplies for power outages or road closures Benton County Emergency Management Ongoing X X X Short-Term #2 Review and update emergency response plans for disruptions of utilities or roads local emergency service agencies, CRCC 1-2 YearsX X X Short-Term #3 Ensure that all critical facilities in Benton County have backup power and emergency operations plans to deal with power outages Benton County Emergency Management, Benton County Facilities 1-2 YearsX X X Exec - 15 Mitigation Plan Goals Addressed Hazard Action Item Coordinating Organizations Timeline Life Safe Critical Facilities and Eme Services Protect Property Disas Resilient Econo P Education, Outr Partner Hazmat Incident Mitigation Action Items Short-Term #1 Ensure that first responders have readily available site-specific knowledge of hazardous chemical inventories in Benton County local fire and law enforcement agencies 1 year X X X Short-Term #2 Enhance emergency planning, emergency response training and equipment to address hazardous materials incidents. local fire and law enforcement agencies Ongoing X X X Long-Term #1 Modify existing codes to prohibit aggravating or creating a hazard in identified risk areas i.e. HAZMAT storage in a floodplain Community Development Departments 5 years X X X X Long-Term #2 Evaluate and assist with upgrade seismic bracing/anchoring for storage of large quantities of hazardous materials and for all Extremely Hazardous Material storage location Benton County Public Works (for county materials), city public works (for city materials), local industry, County Engineer, Benton County Emergency Management 10 years X X X X Exec - 16 Mitigation Plan Goals Addressed Hazard Action Item Coordinating Organizations Timeline Life Safe Critical Facilities and Emerg Protect Property Disaster Resilient Econo Public Education, Outr Partner Terrorism Mitigation Action Items Short-Term #1 Enhance emergency planning, emergency response training and equipment to address potential terrorism incidents. local fire and law enforcement agencies, facility managers Ongoing X X X X X Long-Term #1 Upgrade physical security detection and response capability for critical facilities, including water systems and for any high-profile facilities such as major timber industry facilities and sites with large quantities of hazardous materials facility managers 5 Years X X X X X TABLE OF CONTENTS 1.0 INTRODUCTION ...........................................................................................................1-1 1.1 What is a Mitigation Plan?..................................................................................1-1 1.2 Why is Mitigation Planning Important for Benton County?.................................1-2 1.3 The Benton County Mitigation Plan....................................................................1-6 1.4 Key Concepts and Definitions ............................................................................1-6 1.5 The Mitigation Process.....................................................................................1-10 1.6 The Role of Benefit-Cost Analysis in Mitigation Planning ................................1-13 1.7 Hazard Synopsis...............................................................................................1-13 Chapter 1 Annex: Principles of Benefit-Cost Analysis...........................................1-19 2.0 COMMUNITY PROFILE: BENTON COUNTY .............................................................2-1 2.1 Geography and Climate......................................................................................2-1 2.2 Population and Demographics ...........................................................................2-2 2.3 Employment and Economics..............................................................................2-4 2.4 Housing in Benton County..................................................................................2-7 2.5 Land and Development ......................................................................................2-7 2.6 Regulatory Context: Overview..........................................................................2-10 2.7 Regulatory Context: Oregon Statewide Planning Goal 7 .................................2-10 2.8 Regulatory Context: Benton Code....................................................................2-12 2.9 Community Rating System...............................................................................2-13 2.10 Regulatory Context: Summary Comments....................................................2-13 3.0 PUBLIC PROCESS and COMMUNITY INVOLVEMENT.............................................3-1 3.1 Overview.............................................................................................................3-1 3.2 Steering and Public Committee..........................................................................3-1 4.0 PLAN GOALS, MITIGATION STRATEGIES and ACTION ITEMS..............................4-1 4.1 Overview.............................................................................................................4-1 4.2 Mission Statement..............................................................................................4-2 4.3 Mitigation Plan Goals and Objectives.................................................................4-2 4.4 Benton County Hazard Mitigation Plan Action Items..........................................4-5 5.0 MITIGATION PLAN ADOPTION, MAINTENANCE AND IMPLEMENTATION............5-1 5.1 Overview.............................................................................................................5-1 5.2 Plan Adoption .....................................................................................................5-1 5.3 Implementation ...................................................................................................5-2 5.4 Project Prioritization............................................................................................5-3 5.5 Maintenance .......................................................................................................5-6 i 6.0 FLOOD HAZARDS........................................................................................................6-1 6.1 Historical Floods in Benton County ....................................................................6-1 6.2 The 1996 Flood...................................................................................................6-2 6.3 Flood Hazards and Flood Risk: Within Mapped Floodplains.............................6-3 6.3.1 Overview ..............................................................................................6-3 6.3.2 Flood Hazard Data .............................................................................6-12 6.3.3 Interpreting Flood Hazard Data for Mapped Floodplains...................6-13 6.3.4 Caveats for the Benton County Flood Insurance Study.....................6-14 6.4 Flood Hazards and Flood Risk: Outside of Mapped Floodplains ....................6-15 6.5 Inventory Exposed to Flood Hazards in the Eugene/Springfield Area .............6-16 6.6 Estimating Flood Losses and Flood Risk .........................................................6-20 6.6.1 Flood Loss Estimates.........................................................................6-20 6.2.2 Techniques for More Accurate Flood Loss Estimates........................6-23 6.7 Flood Insurance Data for Benton County .........................................................6-24 6.8 Summary of Flood Risk for Benton County ......................................................6-26 6.9 Common Flood Mitigation Projects and Action Items.......................................6-27 7.0 WINTER STORMS ........................................................................................................7-1 7.1 Overview.............................................................................................................7-1 7.2 Rain Hazard Data...............................................................................................7-2 7.3 Wind Hazard Data ..............................................................................................7-9 7.4 Snow and Ice Hazard Data...............................................................................7-15 7.5 Other Severe Weather Events..........................................................................7-17 7.6 Winter Storm Risk Assessment........................................................................7-19 7.7 Mitigation of Winter Storm Impacts...................................................................7-20 8.0 LANDSLIDES................................................................................................................8-1 8.1 Landslide Overview and Definitions ...................................................................8-1 8.2 Landslide Hazard Assessment for Benton County.............................................8-3 8.3 Landslide Risk Assessment for Benton County ...............................................8-14 8.4 Mitigation of Landslide Risk..............................................................................8-15 9.0 WILDLAND/URBAN INTERFACE FIRES ....................................................................9-1 9.1 Fire Primer..........................................................................................................9-2 9.1.1 Structure Fires......................................................................................9-2 9.1.2 Wildland Fires.......................................................................................9-4 9.1.3 Wildland/Urban Interface Fires.............................................................9-7 9.2 Measures of the Level of Fire Hazard ................................................................9-9 9.3 Historical Data for Wildland Fires in Oregon ....................................................9-11 9.4 Urban/Wildland Interface Fire Hazards for Benton County ..............................9-15 9.5 Fire Protection Service Providers ....................................................................9-20 9.6 Mitigation Strategies.........................................................................................9-27 ii 10.0 EARTHQUAKES .......................................................................................................10-1 10.1 Earthquake Primer..........................................................................................10-1 10.2 Seismic Hazards for Benton County...............................................................10-3 10.3 Other Aspects of Seismic Hazards in Benton County..................................10-10 10.3.1 Soil Effects .....................................................................................10-10 10.3.2 Landslides ......................................................................................10-19 10.3.3 Dam Failures..................................................................................10-19 10.3.4 Tsunamis and Seiches...................................................................10-19 10.4 Risk Assessment for Scenario Earthquakes ................................................10-20 10.4.1 M8.5 Cascadia Subduction Zone Interface Earthquake ................10-20 10.4.2 M7.5 Cascadia Subduction Zone Intraplate Earthquake ...............10-23 10.5 Earthquake Risk Assessment: Technical Guidance....................................10-24 10.5.1 Level Two Risk Assessment ..........................................................10-25 10.5.2 Level Three Risk Assessment........................................................10-25 10.6 Other Earthquake Loss Estimates for Benton County..................................10-27 10.7 Earthquake Hazard Mitigation Projects: General Examples ........................10-30 Appendix: Seismic Retrofit of Monroe High School..............................................10-32 11.0 VOLCANIC HAZARDS..............................................................................................11-1 11.1 Overview.........................................................................................................11-1 11.2 Volcanic Hazard Types...................................................................................11-3 11.3 Volcanic Hazards for Benton County..............................................................11-4 11.4 Mitigation of Volcanic Hazards .......................................................................11-9 12.0 DAM SAFETY............................................................................................................12-1 12.1 Overview of Dams ..........................................................................................12-1 12.2 Dam Primer.....................................................................................................12-2 12.2.1 Dam Nomenclature and Types of Dams..........................................12-2 12.2.2 Dam Failure Modes..........................................................................12-3 12.3 Oregon Dam Data ..........................................................................................12-5 12.4 Dam Failure Hazard Assessment: Benton County.........................................12-6 12.5 Risk Assessment (Preliminary).......................................................................12-8 12.5.1 Flood Damage to Dams ...................................................................12-8 12.5.2 Earthquake Damage to Dams..........................................................12-9 12.5.3 Loss Estimates (Preliminary) .........................................................12-10 12.6 Mitigation Strategies.....................................................................................12-12 References ...........................................................................................................12-13 13.0 DISRUPTION OF UTILITY AND TRANSPORTATION SYSTEMS ..........................13-1 13.1 Transportation Systems..................................................................................13-1 13.2 Utility Systems - Overview..............................................................................13-3 13.3 Potable Water Systems..................................................................................13-5 13.4 Wastewater Systems......................................................................................13-6 13.5 Natural Gas Systems......................................................................................13-6 13.6 Telecommunications Systems........................................................................13-7 iii 13.7 Electric Power Systems..................................................................................13-8 13.8 Impacts on Benton County and Mitigation Action Items...............................13-10 14.0 HAZARDOUS MATERIALS......................................................................................14-1 14.1 Introduction.....................................................................................................14-1 14.2 Effects of Hazardous Materials on Humans...................................................14-2 14.3 Classification Systems and Emergency Response Protocols........................14-3 14.4 Statutory and Regulatory Context ..................................................................14-6 14.5 Fixed Site Hazardous Materials Locations in Benton County ........................14-7 14.6 Commentary on Inventory of Extremely Hazardous Substances...................14-9 14.7 Benton County Locations with Large Inventories of Hazardous Materials...14-10 14.7.1 Hewlett Packard, Corvallis .............................................................14-10 14.7.2 OSU Nuclear Reactor, Corvallis.....................................................14-11 14.7.3 Western Pulp Products, Corvallis...................................................14-13 14.7.4 Wilbur Ellis Co., Monroe.................................................................14-14 14.8 Hazardous Materials Transport: Truck, Rail and Pipelines .........................14-16 14.8.1 Overview and Truck Shipments .....................................................14-16 14.8.2 Rail Shipments ...............................................................................14-18 14.8.3 Pipelines.........................................................................................14-18 14.9 Reference Information for Hazardous Materials Incidents Emergency Response..............................................................................................................14-19 14.10 Vulnerability and Risk Assessments...........................................................14-23 14.11 Summary and Mitigation Strategies............................................................14-24 14.11.1 Planning and Response...............................................................14-24 14.11.2 Mitigation Measures .....................................................................14-25 References ...........................................................................................................14-27 15.0 TERRORISM .............................................................................................................15-1 15.1 Overview.........................................................................................................15-1 15.2 Threat Spectrum.............................................................................................15-1 15.3 Mitigation Actions ...........................................................................................15-3 APPENDIX: NATURAL HAZARDS RESOURCE DIRECTORY.......................................A-1 APPENDIX: SPECIAL DISTRICTS/MULTI-JURISDICTIONAL PLANS..........................B-1 iv 1.0 INTRODUCTION 1.1 What is a Mitigation Plan? The communities of Benton County are subject to a wide range of natural and human- caused hazards, including: floods, winter storms, landslides, wildland/urban interface fires, earthquakes, dam failures, hazardous material spills, and many others. The impact of a hazard event on a community may be minor - a few inches of water in a street - or it may be major - with damages reaching millions of dollars. There have been several recent events in Benton County with widespread damages and impacts: ? The flooding in February 1996 affected many portions of Benton County. A combination of rain, warmer temperatures causing snow melt, and then more rain caused flooding in the southern part of Corvallis and southern Benton County. Shelters were opened, some families were evacuated by boat, and massive sandbagging efforts were conducted to save governmental and private structures. This winter storm also brought numerous landslides and resulted in the closure of a lifeline transportation route for about 24 hours. ? The winter storm in December 2003 and January 2004 struck the Pacific Northwest and rapidly developed into a full-blown snowstorm in elevations as low as 500 feet. There was significant snowfall and freezing rain across the entire county. Freezing rain fell along the coast and throughout the Willamette Valley causing widespread ice accumulations. Critical services within Benton County were disrupted, with about 10,000 consumers without electricity for 3 to 4 days. Local governments were closed, and the local hospital discharged non-critical patients due to an increase in patient admissions that were related to the storm. Emergency snow removal was conducted to keep primary roads open. Transport of emergency workers by Search and Rescue groups kept care facilities and medical facilities operational. One person died as a result of the power outage. The impacts of hazard events on communities can be devastating: the total damages, economic losses, casualties, disruption, hardships and suffering are often far greater than the physical damages alone. Furthermore, recovery from major events often takes many years and some heavily impacted communities may never fully recover. Completely eliminating the risk of future disasters is neither technologically possible nor economically feasible. However, substantially reducing the negative impacts of future disasters is achievable with the development and implementation of a pragmatic Hazard Mitigation Plan. Mitigation simply means actions that reduce the potential for negative impacts from future disasters. Mitigation actions reduce future damages, losses and casualties. This Mitigation Plan addresses all levels of natural hazard events and some human- caused hazards as well. The Plan includes minor events such as winter storms or 1-1 localized storm water flooding that may happen in some locations almost every year and localized events such as landslides or mudslides. The plan also includes larger events such as major floods, earthquakes, or major wildland/urban interface fires that may affect large numbers of residents in Benton County, with very high levels of damages and losses, albeit with much lower probabilities of occurrence. The Benton County mitigation plan has several key elements. 1. Each hazard that may impact Benton County significantly is reviewed to determine the probability (frequency) and severity of likely hazard events. 2. The vulnerability of Benton County to each hazard is evaluated to determine the likely extent of physical damages, casualties, and economic impacts. 3. A range of mitigation alternatives are evaluated to identify those with the greatest potential to reduce future damages and losses in Benton County, to protect facilities deemed critical to the community?s well being, and that are desirable from the community?s political and economic perspectives. 1.2 Why is Mitigation Planning Important for Benton County? Effective mitigation planning will help the residents of Benton County deal with natural and anthropogenic (human-caused) hazards realistically and rationally. That is, it will help identify specific locations in Benton County where the level of risk from one or more hazards may be unacceptably high and then find cost effective ways to reduce such risk. Mitigation planning strikes a pragmatic middle ground between unwisely ignoring the potential for major hazard events on one hand and unnecessarily overreacting to the potential for disasters on the other hand. Furthermore, the Federal Emergency Management Agency (FEMA) now requires each local government entity to adopt a multi-hazard mitigation plan to remain eligible for future pre- or post-disaster FEMA mitigation funding. Thus, an important objective in developing this plan is to maintain eligibility for FEMA funding and to enhance Benton County?s ability to attract future FEMA mitigation funding. The Plan is specifically designed to help Benton County gather the data necessary to compete successfully for future FEMA funding of mitigation projects. FEMA requires that all FEMA-funded hazard mitigation projects must be ?cost-effective? (i.e., the benefits of a project must exceed the costs). Benefit-cost analysis is thus an important component of mitigation planning, not only to meet FEMA requirements, but also to help evaluate and prioritize potential hazard mitigation projects in Benton County, regardless of whether funding is from FEMA, state or local government or from private sources. 1-2 1-3 Hazard mitigation planning is applicable to Benton County as a whole, including the entire population and all of the built environment of buildings (residential, commercial, and public) and infrastructure (transportation and utility systems). However, for mitigation planning purposes and for implementation of mitigation actions, facilities designated as critical for the well being of residents of Benton County are given a higher priority. A brief summary of the types of critical facilities in Benton County is given below in Table 1.1. 1-4 Table 1.1 Types of Critical Facilities in Benton County Category Critical Functions High Priority Medium Priority Emergency Services Facilities critical for immediate emergency response, including life safety Fire Stations YES Police Stations YES Ambulance Services YES Emergency Operations Centers YES Emergency Shelters YES Medical Facilities Facilities providing direct patient care, including hospitals, clinics, and nursing homes Hospitals and Urgent Care Facilities YES Other Medical Facilities YES Special Needs Populations Facilities housing people that may need assistance is evacuation from emergencies Elderly Housing High occupancy facilities Low occupancy facilities Schools (K-12) YES Schools (Higher Education) YES Jails YES Utilities Telecommunications Facilities for transmission, switching and distribution of telephone traffic PSAPs (911 centers) and Central Offices (switching) Trunk lines Electric Power Facilities for generation, transmission and distribution of electric power High voltage substations and transmission lines Other substations and transmission lines, trunk distribution lines Natural Gas Facilities for transmission and distribution ofnatural gas Transmission lines and compressor stations Water Facilities for treatment and distribution of potable and irrigation water Major reservoirs, well fields, treatment plants and major pumping plants Smaller reservoirs and pumping plants Wastewater Facilities for pumping and treatment of wastewater Treatment plants and major pumping plants 1-5 Category Critical Functions High Priority Medium Priority Dams Facilities to impound water for flood control, power generation and water supply Major dams upstream of population centers Smaller dams and dams not upstream of population centers Transportation Systems Roadways Necessary for emergency response, public safety and disaster recovery Major highways, arterials, and bridges on such roads Secondary roads and bridges Air, rail, and water transport These transport modes are of secondary importance for Benton County Not at this time Not at this time Hazmat Facilities Facilities that manufacture, store, use, or transport hazardous materials Sites with large inventories of hazardous materials Sites with smaller inventories of hazardous materials 1.3 The Benton County Mitigation Plan This Benton County Mitigation Plan is built is upon a quantitative assessment of each of the major hazards that may impact Benton County, including their frequency, severity, and areas of the County likely to be affected. The hazards addressed include: floods, severe winter storms (including windstorms), landslides, wildland/urban interface fires, earthquakes, volcanic eruptions, dam failures, utility and transportation disruptions, hazmat incidents, and terrorism. The Benton County Mitigation plan includes a quantitative assessment of the vulnerability of buildings, infrastructure, and people to each of these hazards, to the extent possible with existing data. The plan also includes an evaluation of the likely magnitude of the impacts of future disasters on Benton County. These reviews of the hazards and the vulnerability of Benton County to these hazards are the foundation of the mitigation plan. From these assessments, high hazard areas where buildings, infrastructure, and/or people may be at high risk are identified whenever possible. These high-risk situations then become priorities for future mitigation actions to reduce the negative impacts of future disasters on Benton County. The Benton County Mitigation Plan deals with hazards realistically and rationally and also strikes a balance between suggested physical mitigation measures to eliminate or reduce the negative impacts of future disasters and enhancements in land use planning to reduce the potential for negative impacts of disasters on new development. Finally, the plan suggests better emergency planning to help prepare the community to respond to and recover from disasters for which physical mitigation measures are not possible or not economically feasible. 1.4 Key Concepts and Definitions The central concept of mitigation planning is that mitigation reduces risk. Risk is defined as the threat to the built environment posed by the hazards being considered. That is, risk is the potential for damages, losses and casualties arising from the impact of hazards on the built environment. The extent of risk depends on the combination of hazard and exposure as shown in Figure 1.2 below. 1-6 Figure 1.2 Hazard and Exposure Combine to Produce Risk HAZARD EXPOSURE RISK Frequency + Value and = Threat to the and Severity Vulnerability Built Environment of Hazard Events of Inventory Thus, there are four key concepts that govern hazard mitigation planning: hazard, exposure, risk and mitigation. Each of these key concepts is addressed in turn. HAZARD refers to natural or anthropogenic events that potentially may cause damages, losses or casualties (e.g., floods, winter storms, landslides, earthquakes, hazardous material spills, etc.). Hazards are characterized by their frequency and severity and by the geographic area affected. Each hazard is characterized differently, with appropriate parameters for the specific hazard. For example, floods may be characterized by the frequency of flooding, along with flood depth and flood velocity. Winter storms may be characterized by the amount of rainfall in a 24-hour period, by the wind speed, by the amount of snow or ice associated with a storm. Earthquakes may be characterized by the severity and duration of ground motions and so on. A hazard, by itself, may not result in any negative impacts on a community. For example, a highly flood-prone five acre parcel may typically experience several shallow floods per year, with several feet of water expected in a 50-year flood event and more than six feet of water expected in a 100-year flood event. However, the parcel may be wetlands adjacent to a tidal marsh that floods daily, with no development (structures or infrastructure) on the parcel. In this case, the frequent flooding does not have any negative impacts on the community. Indeed, in such circumstances, the very frequent flooding (i.e., high hazard) may be beneficial in providing wildlife habitat. The important point here is that hazards do not produce risk, unless there is vulnerable inventory exposed to the hazard. In the context of mitigation planning, ?inventory? means simply people, buildings, or infrastructure exposed to damages from one or more natural or manmade hazards. EXPOSURE is the quantity, value and vulnerability of the built environment (inventory of buildings and infrastructure) in a particular location subject to one or more hazards. Inventory is described by the number, size, type, use, and occupancy of buildings and by the infrastructure present. Infrastructure includes roads and other transportation systems, utilities (potable water, wastewater, natural gas, electric power), telecommunications systems and so on. 1-7 Inventory varies markedly in its importance to a community and thus varies markedly in its importance for hazard mitigation planning. Some types of facilities, ?critical facilities,? are especially important to a community, particularly during disaster situations. Examples of critical facilities include police and fire stations, hospitals, schools, emergency shelters, 911 centers, and other important buildings. Critical facilities may also include infrastructure elements that are important links or nodes in providing service to large numbers of people such as a potable water source, an electric power substation and so on. ?Links? are elements such as water pipes, electric power lines, telephone cables that connect portions of a utility or transportation system. ?Nodes? are locations with important functions, such as pumping plants, substations, or switching offices. For hazard mitigation planning, inventory is characterized not only by the quantity and value of buildings or infrastructure present but also by its vulnerability to each hazard under evaluation. For example, a given facility may be vulnerable to flood damages and earthquake damages or to flood damages only or to earthquake damages only. Depending on the hazard, different measures of vulnerability must be used. RISK is the threat to the built environment (buildings and infrastructure) and people - the potential for damages, losses and casualties arising from hazards. Risk results from the combination of Hazard and Exposure. That is, when the geographic areas affected by one or more hazards contain people, buildings, and infrastructure vulnerable to damage from the hazard(s). For mitigation planning, evaluation of risk generally emphasizes the built environment and people. However, risk also includes the potential for environmental damage. Risk is the potential for future damages, losses or casualties. A disaster event happens when a hazard event is combined with vulnerable inventory (that is when hazard event strikes vulnerability inventory exposed to the hazard). The highest risk in a community occurs in high hazard areas (frequent and/or severe hazard events) with large inventories of vulnerable buildings or infrastructure. However, high risk can also occur with only moderately high hazard, if there is a large inventory of highly vulnerable inventory exposed to the hazard. For example, seismic hazard is lower in Oregon than in the seismically active areas of California. However, for some buildings, seismic risk in Oregon may be comparable to or even higher than seismic risk in California, due to the very recent adoption in Oregon of seismic design standards commensurate with current understanding of seismic hazards in Oregon. Much of the building inventory in Oregon is vulnerable to earthquake damages because older buildings were generally designed and built too much lower seismic standards than currently required in Oregon. Conversely, a high hazard area can have relatively low risk if the inventory is resistant to damages (e.g., elevated to protect against flooding or strengthened to minimize earthquake damages). 1-8 Figure 1.3 Risk Results from the Combination of Hazard and Exposure RISK . . . MITIGATION means actions to reduce the risk due to hazards. Mitigation actions reduce the potential for damages, losses, and casualties in future disaster events. Repair of buildings or infrastructure damaged in a disaster is not mitigation because repair simply restores a facility to its pre-disaster condition and does not reduce the potential for future damages, losses, or casualties. Hazard mitigation projects may be initiated proactively - before a disaster, or after a disaster has already occurred. In either case, the objective of mitigation is always to reduce future damages, losses or casualties. 1-9 A few of the most common types of mitigation projects are shown below in Table 1.4. Table 1.4 Common Mitigation Projects Hazard Mitigation Project Flood Build or improve levees or flood walls Improve channels for flood control Improve drainage systems and culvert capacities Create detention ponds for storage Relocate, elevate or floodproof flood-prone structures Acquire and demolish highly flood-prone structures Winter Storms Add emergency generators for critical facilities Improve redundancy of utility systems Trim trees to reduce failures of utility lines Earthquakes Upgrade seismic performance of buildings Upgrade seismic performance of infrastructure Landslides Remediate slide conditions Relocate utility lines or structures Wildland/Urban Interface Fires Increase fire safe construction practices Vegetation (fuel load) control General Enhance emergency planning and mutual aid Expand public education programs The mitigation project list above is not comprehensive and mitigation projects can encompass a broad range of other actions to reduce future damages, losses, and casualties. 1.5 The Mitigation Process The key element for all hazard mitigation projects is that they reduce risk. The benefits of a mitigation project are the reduction in risk (i.e., the avoided damages, losses, and casualties attributable to the mitigation project). In other words, benefits are simply the difference in expected damages, losses, and casualties before mitigation (as-is conditions) and after mitigation. These important concepts are illustrated below in Figure 1-5. 1-10 Figure 1.5 Mitigation Projects Reduce Risk RISK BEFORE MITIGATION BENEFITS OF MITIGATION REDUCTION RISK IN RISK AFTER MITIGATION Quantifying the benefits of a proposed mitigation project is an essential step in hazard mitigation planning and implementation. Only by quantifying benefits is it possible to compare the benefits and costs of mitigation to determine whether or not a particular project is worth doing (i.e., is economically feasible). Real world mitigation planning almost always involves choosing between a range of possible alternatives, often with varying costs and varying effectiveness in reducing risk. Quantitative risk assessment is centrally important to hazard mitigation planning. When the level of risk is high, the expected levels of damages and losses are likely to be unacceptable and mitigation actions have a high priority. Thus, the greater the risk, the greater the urgency of undertaking mitigation actions. Conversely, when risk is moderate both the urgency and the benefits of undertaking mitigation are reduced. It is neither technologically possible nor economically feasible to eliminate risk completely. Therefore, when levels of risk are low and/or the cost of mitigation is high relative to the level of risk, the risk may be deemed acceptable (or at least tolerable). Therefore, proposed mitigation projects that address low levels of risk or where the cost of the mitigation project is large relative to the level of risk are generally poor candidates for implementation. The overall mitigation planning process is outlined in Figure 1.6 on the following page. The flow chart below outlines the major steps in Hazard Mitigation Planning and Implementation for Benton County. The first steps are quantitative evaluation of the hazards (frequency and severity) impacting Benton County and of the inventory (people, buildings, infrastructure) exposed to these hazards. Together these hazard and exposure data determine the level of risk for specific locations, buildings or facilities in Benton County. The next key step is to determine whether or not the level of risk posed by each of the hazards impacting Benton County is acceptable or tolerable. Only the residents of 1-11 Benton County can make this determination. If the level of risk is deemed acceptable or at least tolerable, then mitigation actions are not necessary or at least not a high priority. On the other hand, if the level of risk is deemed not acceptable or tolerable, then mitigation actions are desired. In this case, the mitigation planning process moves on to more detailed evaluation of specific mitigation alternatives, prioritization, funding and implementation of mitigation measures. As with the determination of whether or not the level of risk posed by each hazard is acceptable or not, decisions about which mitigation projects to undertake can be made only by the residents of Benton County. For reference, a more detailed discussion of the overall mitigation planning process, including each step in the planning process flow chart shown below in Figure 1.6, is given in Chapter 2 of the Regional All Hazard Mitigation Master Plan for Benton, Benton and Linn Counties (in both the Phase One and Phase Two reports). Figure 1.6 The Mitigation Planning Process Implement Mitigation Measures Reduce Risk Mitigation Planning Flowchart Prioritize Mitigation Alternatives Benefit-Cost Analysis and related tools Obtain Funding Find Solutions to Risk Identify Mitigation Alternatives Risk Not Acceptable? Mitigation Desired Acceptable? Risk Acceptable? Mitigation Not Necessary Risk Assessment Quantify the Threat to the Built Environment Is Level of Risk 1-12 1.6 The Role of Benefit-Cost Analysis in Mitigation Planning Communities that are considering whether or not to undertake mitigation projects must answer questions that don?t always have obvious answers, such as: What is the nature of the hazard problem? How frequent and how severe are hazard events? Do we want to undertake mitigation measures? What mitigation measures are feasible, appropriate, and affordable? How do we prioritize between competing mitigation projects? Are our mitigation projects likely to be eligible for FEMA funding? Benefit-cost analysis is a powerful tool that can help communities provide solid, defensible answers to these difficult socio-political-economic-engineering questions. Benefit-cost analysis is required for all FEMA-funded mitigation projects, under both pre-disaster and post-disaster mitigation programs. Thus, communities seeking FEMA funding must understand benefit-cost analysis. However, regardless of whether or not FEMA funding is involved, benefit-cost analysis provides a sound basis for evaluating and prioritizing possible mitigation projects for any natural hazard. Benefit-cost analysis software, technical manuals and a wide range of guidance documents are available from FEMA at no cost to communities. A Benefit-Cost Analysis Toolkit CD, which contains all of the FEMA benefit-cost materials, is available from FEMA. The publication What is a Benefit? Draft Guidance for Benefit-Cost Analysis is particularly recommended as a general reference for benefit-cost analysis. This publication includes categories of benefits to count for mitigation projects for various types of buildings, critical facilities, and infrastructure and has simple, standard methods to quantity the full range of benefits for most types of mitigation projects. The principles of benefit-cost analysis are briefly summarized in the Annex at the end of this Chapter. 1.7 Hazard Synopsis To set the overall context of hazard mitigation planning, we briefly review the major hazards that impact Benton County. Different parts of Benton County vary in topography, climate, population, development patterns and so on. Similarly, the impact of many hazards on communities in Benton County varies with location within the 1-13 County. Some hazards affect the entire County, while some hazards have only localized potential consequences. Floods. Nearly every community in Benton County is affected by flood hazards, to at least some extent. Most communities in Benton County have areas of flood plains mapped by FEMA. These include areas along the Willamette River, as well as areas along smaller creeks, Other portions of Benton County, outside of the mapped floodplains, are also subject to significant, repetitive flooding from local storm water drainage. Winter Storms. All of Benton County is subject to the effects of winter storms, including wind, rain, snow and ice, as well as secondary effects such as power outages. However, the severity of impacts and types of impacts vary with location and with elevation. Landslides. Portions of the hilly areas of Benton County, especially the in the Coast Range, in are subject to landslides or debris flows (mudslides), which may affect buildings, roads, and utilities. Wildland/Urban Interface Fires. Much of Benton County is subject to the risk of wildland fires, including the hilly-forested areas of the Coast Range. As a result, many residential areas bordering or impinging into forested areas near the edges of the developed areas of Benton County may have high levels of risk from wildland/urban interface fires. Thus, portions of most communities in Benton County have at least some level of risk from wildland/urban interface fires. Earthquakes. All of Benton County is subject to the impacts of earthquakes, including not only major earthquakes on the Cascadia Subduction Zone off the Oregon coast, but also smaller crustal earthquakes within western Oregon. Volcanic Hazards. All of Benton County is subjected, to a minor degree, to volcanic hazards from eruptions in the Cascades (e.g., Mount Hood, the Three Sisters). For Benton County, the impacts of volcanic events are likely to be only minor ash falls, with perhaps some impact on public water supplies from ash causing high turbidity in drinking water supplies. Dam Failures. Many heavily populated portions of Benton County along the Willamette River are in the inundation areas from dam failures. While dam failures are highly unlikely, the consequences of failure would be high. Disruption of Utility and Transportation Systems. All of Benton County is also subject to disruption of utility and transportation systems 1-14 from winter storms and other natural hazards, as well as from anthropogenic causes. Hazmat Incidents. Human-caused hazards, such as hazardous material releases, are possible nearby or downwind from fixed site concentrations (e.g., industrial sites) as well as along transportation corridors from truck or railroad accidents. All populated areas of Benton County are subject to HAZMAT incidents. Terrorism. The term ?terrorism? is broadly inclusive of all deliberate malevolent actions intended to damage property or inflict casualties. Terrorism includes actions by outsiders (domestic or international groups or individuals,), insiders (e.g., employees), and cyber-terrorists (computer hackers). Any community in Benton County could potentially be affected by terrorist actions. According to the FBI, acts of violence in protest of harm to animals or to the environment, is the United States' number one domestic terrorism threat. In evaluating these natural or human-caused hazards, it is important to recognize that the risk to Benton County (i.e., the potential for damages, economic losses, and casualties) varies markedly from one hazard to another. As discussed in more detail in Section 1.4, risk depends on the combination of the frequency and severity of hazard events and on the value and vulnerability of infrastructure, buildings, and people to each potential hazard. Risk is thus always probabilistic in nature. Some hazard events, such as winter storms, happen every year to at least some extent. Other hazard events, such as major earthquakes may happen only once every few hundred years. However, risk from earthquakes may not be low, even though the frequency of occurrence is low, because the consequences (damage, economic losses, and casualties) may be very high. The relative risk posed to Benton County by each of the 10 hazards covered in this mitigation plan is summarized below in Table 1.7. Table 1.7 Relative Risk to Benton County Hazard Risk Flood High Earthquake High Dam Failure High Winter storms (Severe weather) Moderate Wildand/Urban Interface Fires Moderate Disruption of Utility and Transportation Systems Moderate Hazmat Incidents Low/Moderate Terrorism Low/Moderate Landslides Low Volcanic Eruptions (Ash Falls) Low 1-15 Hazards affecting Benton County have also been ranked for emergency planning purposes (Benton County Hazard Analysis, June 1, 2002). These results are shown below in Table 1.8. These hazard scores are based on the Oregon Office of Emergency Management?s hazard matrix criteria, which include measures of the event history (number of events in last 100 years), vulnerability (percentage of population likely to be affected), maximum threat (percentage of population the could be affected in a worst- case incident) and probability (likelihood of occurrence in specified time periods). These rankings are useful for emergency response planning, but are not necessarily good measures of risk because they do not take into account the severity of impacts (damages, economic losses, and casualties) and the probability of hazard events is included only semi-quantitatively. For these reasons, these ranking scores differ somewhat from those shown above in Table 1.7. Table 1.8 Benton County Hazards Analysis Hazard Points Severe Weather 240 Earthquake 195 Hazardous Materials Incident 165 Fire/Wildland Fire 165 Flood 165 Utility failure 162 Enemy Attack (War) 134 Civil Disorder (Terrorism) 120 Drought 100 Volcanic Ash Fallout 92 Dam Failure 84 Radiological Incident 64 In summary, there are many natural and human-caused hazards which affect all or large portions of Benton County. The remaining chapters of this mitigation plan include the following. Chapter 2 provides a brief community profile for Benton County. Chapter 3 documents the community involvement and public process involved in developing this mitigation plan. Chapter 4 outlines the mitigation plan goals, mitigation strategies, and action items. Chapter 5 documents the formal process of plan adoption, implementation, and maintenance. 1-16 Chapters 6 through 15 cover each of the major hazards addressed in this mitigation plan, including: floods, winter storms, landslides, wildland/urban interface fires, earthquakes, volcanic hazards, dam safety, disruption of utility and transportation systems, hazmat incidents, and terrorism. 1-17 1-18 Chapter 1 Annex Principles of Benefit-Cost Analysis Benefit-cost analysis is the tool that provides answers to a central question for hazard mitigation projects: ?Is it worth it?? If hazard mitigation were free, individuals and communities would undertake mitigation with robust enthusiasm and the risks from hazards would soon be greatly reduced. Unfortunately, mitigation is not free, but often rather expensive. For a given situation, is the investment in mitigation justified? Is the owner (public or private) better off economically to accept the risk or invest now in mitigation to reduce future damages? These are hard questions to answer! Benefit- cost analysis can help a community answer these difficult questions. In the complicated real world of mitigation projects, there are many factors that determine whether or not a mitigation project is worth doing or which of two or more mitigation projects should have the highest priority. Consider a town that has two flood prone neighborhoods and each neighborhood desires a mitigation project. The two neighborhoods have different numbers of houses, different value of houses, different frequencies and severity of flooding. The first neighborhood proposes storm water drainage improvements at a cost of $3.0 million. The second neighborhood wants to elevate houses at a cost of $3.0 million. Which of these projects should be completed? Both? One or the Other? Neither? Which project should be completed first if there is only funding for one? Are there alternative mitigation projects that are more sensible or more cost-effective than the proposed projects? Such complex socio-political-economic-engineering questions are nearly impossible to answer without completing the type of quantitative flood risk assessment and benefit- cost analysis discussed below. In determining whether or not a given mitigation project is worth doing, the level of risk exposure without mitigation is critical. Consider a hypothetical $1,000,000 mitigation project. Whether or not the project is worth doing depends on the level of risk before mitigation and on the effectiveness of the project in reducing risk. For example, if the before mitigation risk is low (a subdivision street has a few inches of water on the street every couple of years or a soccer field in a city park floods every five years or so) the answer is different than if the before mitigation risk is high (100 or more houses are expected to have flooding above the first floor every 10 years or a critical facility is expected to be shut down because of flood damages once every five years). All well-designed mitigation projects reduce risk (badly designed projects can increase risk or simply transfer risk from one community to another). However, just because a mitigation project reduces risk does not make it a good project. A $1,000,000 project that avoids an average of $100 per year in flood damages is not worth doing, while the same project that avoids an average of $200,000 per year in flood damages is worth doing. 1-19 The principles of benefit-cost analysis are briefly summarized here. The benefits of a hazard mitigation project are the reduction in future damages and losses, that is, the avoided damages and losses that are attributable to a mitigation project. To conduct benefit-cost analysis of a specific mitigation project the risk of damages and losses must be evaluated twice: before mitigation and after mitigation, with the benefits being the difference. The benefits of a hazard mitigation project are thus simply avoided future damages and losses. Because the benefits of a hazard mitigation project accrue in the future, it is impossible to know exactly what they will be. For example, we do not know when future floods or other natural hazards will occur or how severe they will be. We do know, however, the probability of future floods or other natural hazards (if we have appropriate hazard data). Therefore, the benefits of mitigation projects must be evaluated probabilistically and expressed as the difference between annualized damages before and after mitigation. The following simplified example illustrates the principles of benefit-cost analysis; more details are given in the examples in the Appendices. To illustrate the principles of benefit-cost analysis, we consider a hypothetical single- family house in the town of Acorn, with the house located on the banks of Squirrel Creek. The house is a one-story house, about 1500 square feet on a post foundation, with a replacement value of $60/square foot (total $90,000). We have flood hazard data for Squirrel Creek (stream discharge and flood elevation data) and elevation data for the first floor of the house. Therefore, we can calculate the annual probability of flooding in one-foot increments, as shown below. Table 1.9 Damages Before Mitigation Flood Depth (feet) Annual Probability of Flooding Scenario Damages and Losses Per Flood Event Annualized Flood Damages and Losses 0 0.2050 $6,400 $1,312 1 0.1234 $14,300 $1,765 2 0.0867 $24,500 $2,124 3 0.0223 $28,900 $673 4 0.0098 $32,100 $315 5 0.0036 $36,300 $123 Total Expected Annual (Annualized) Damages and Losses $6,312 1-20 Flood depths shown above in Table 1.9 are in one-foot increments of water depth above the lowest floor elevation. Thus, a ?3" foot flood means all floods between 2.5 feet and 3.5 feet of water depth above the floor. We note that a ?0" foot flood has, on average, damages because this flood depth means water plus or minus 6" of the floor; even if the flood level is a few inches below the first floor, there may be damage to flooring and other building elements because of wicking of water. The Scenario (per flood event) damages and losses include expected damages to the building, content, and displacement costs if occupants have to move to temporary quarters while flood damage is repaired. The Annualized (expected annual) damages and losses are calculated as the product of the flood probability times the scenario damages. For example, a 4-foot flood has slightly less than a 1% chance per year of occurring. If it does occur, we expect about $32,100 in damages and losses. Averaged over a long time, 4-foot floods are thus expected to cause an average of about $315 per year in flood damages. Note that the smaller floods, which cause less damage per flood event, actually cause higher average annual damages because the probability of smaller floods is so much higher than that for larger floods. With these data, the house is expected to average $6312 per year in flood damages. This expected annual or ?annualized? damage estimate does not mean that the house has this much damage every year. Rather, in most years there will be no floods, but over time the cumulative damages and losses from a mix of relatively frequent smaller floods and less frequent larger floods is calculated to average $6312 per year. The calculated results in Table 1.9 are the flood risk assessment for this house for the as-is, before mitigation situation. The table shows the expected levels of damages and losses for scenario floods of various depths and also the annualized damages and losses. The risk assessment shown in Table 1.9 shows a high flood risk, with frequent severe flooding which the owner deems unacceptable. Therefore he explores mitigation alternatives to reduce the risk: the example below is to elevate the house 4 feet. Table 1.10 Damages After Mitigation Flood Depth (feet) Annual Probability of Flooding Scenario Damages and Losses Per Flood Event Annualized Flood Damages and Losses 0 0.2050 $0 $0 1 0.1234 $0 $0 2 0.0867 $0 $0 1-21 3 0.0223 $0 $0 4 0.0098 $6,400 $63 5 0.0036 $14,300 $49 $112 By elevating the house 4 feet, the owner has reduced his expected annual (annualized) damages from $6312 to $112 (98% reduction) and greatly reduced the probability or frequency of flooding affecting his house. The annualized benefits are the difference in the annualized damages and losses before and after mitigation or $6312 - $112 = $6200. Is this mitigation project worth doing? Common sense says yes, because the flood risk appears high: the annualized damages before mitigation are high ($6,312). To answer this question more quantitatively, we complete our benefit-cost analysis of this project. One key factor is the cost of mitigation. A mitigation project that is worth doing at one cost may not be worth doing at a higher cost. Let?s assume that the elevation costs $20,000. This $20,000 cost occurs once, up front, in the year that the elevation project is completed. The benefits, however, accrue statistically over the lifetime of the mitigation project. Following FEMA convention, we assume that a residential mitigation project has a useful lifetime of 30 years. Money (benefits) received in the future has less value than money received today because of the time value of money. To take the time value of money into account, we need to do what is known as a ?present value calculation.? We compare the present value of the anticipated stream of benefits over 30 years in the future to the up-front out-of-pocket cost of the mitigation project. A present value calculation depends on the lifetime of the mitigation project and on what is known as the discount rate. The discount rate may be viewed simply as the interest rate you might earn on the cost of the project if you didn?t spend the money on the mitigation project. Let?s assume that this mitigation project is to be funded by FEMA, which uses a 7% discount rate to evaluate hazard mitigation projects. With a 30-year lifetime and a 7% discount rate, the ?present value coefficient? which is the value today of $1.00 per year in benefits over the lifetime of the mitigation project is 12.41. That is, each $1.00 per year in benefits over 30 years is worth $12.41 now. The benefit-cost results are now as follows. Table 1.11 Benefit-Cost Results Annualized Benefits $6,200 Present Value Coefficient 12.41 Net Present Value of Future Benefits $76,942 Mitigation Project Cost $20,000 1-22 Benefit-Cost Ratio 3.85 These results indicate a benefit-cost ratio of 3.85. Thus, in FEMA?s terms the mitigation project is cost-effective and eligible for FEMA funding. Taking into account the time value of money, which is essential for a correct economic calculation, results in lower benefits than if we simply multiplied the annual benefits times the 30-year project useful lifetime. Economically, simply multiplying the annual benefits times the lifetime would ignore the time value of money and thus gives an incorrect, spurious result. The above discussion of benefit-cost analysis of a flood hazard mitigation project is intended to illustrate the basic concepts. Very similar principles apply to mitigation projects for earthquakes or any other natural hazards. The role of benefit-cost analysis in prioritizing and implementing mitigation projects in Benton County is also addressed in Chapter 4 (Plan Goals, Mitigation Strategies and Action Items). More detailed example evaluations mitigation projects for Benton County are given in the Appendices. 1-23 This Page Left Blank 1-24 2.0 Community Profile: Benton County 2.1 Geography and Climate Benton County is located in western Oregon and covers about 676 square miles. The geography, topography, climate, and other natural attributes such as vegetation vary significantly with location in Benton County. The geographic diversity of Benton County is an important factor to consider in mitigation planning for natural and human-caused hazards. The relative impacts of some natural hazards such as winter storms vary with location in Benton County. Other hazards such as landslides and wildland urban interface fires vary spatially within the County, depending on local topography, rainfall, and vegetation. Other hazards such as earthquakes vary more or less smoothly across Benton County. For hazard mitigation planning, we consider two main physiographic regions within Benton County, based on nomenclature commonly used by the National Weather Service: The Coast Range, in the western portion of Benton County, is a relatively low population, heavily forested area, generally characterized by heavy rainfalls, although the eastern slopes in Benton County have lower rainfall than do the western slopes. The Willamette Valley in eastern Benton County, which is characterized by flat or gently hilly topography, is the most heavily populated area. In addition to these two main physiographic regions of Benton County, there are additional descriptive classifications of geographic factors that are used for specific hazards. For example, for wildland or wildland/urban interface fire risk, the Oregon Department of Forestry commonly considers several regions, two of which encompass Benton County. The Coast Range includes the wetter and typically steeper slope portions of the coastal mountains. The Interior Region includes the drier foothills on both sides of the Willamette Valley. The climate for Benton County is moderate. Mean daily temperatures range from highs of about 81 degrees and lows of about 51 degrees in July and August to highs of about 46 degrees and lows of about 33 or 34 degrees in December and January (Corvallis, Oregon State University weather station data). The average annual rainfall is about 41 inches. Average monthly precipitation varies from about 6 to 7 inches in November through January to about 0.4 inch in July. Average annual snowfall is about 6.1 inches. At higher elevations in the Coast Range, temperatures are typically lower, with higher amounts of precipitation. Average annual precipitation exceeds 140 inches per year in the Coast Range in western Benton County. 2-1 2.2 Population and Demographics Benton County was created from Polk County in 1847 from an area originally inhabited by the Klickitat and Calapooias Native Americans. When created, Benton County extended from the Willamette River to the coast and south to the California border. Lane, Douglas, Jackson, Lincoln, Josephine, Curry and Coos Counties were created later from portions of the original Benton County. The city of Marysville, which became the county seat in 1851, was renamed Corvallis in 1853. Corvallis was incorporated as a city in 1857. Oregon State University was founded in Corvallis in 1862 as the Oregon State Agricultural College and has since become a major educational institution with about 20,000 students and an important presence in Benton County. Benton County population (2000 Census) was 78,153. The 2003 population estimate was 79, 335. Population data for Benton County and for the incorporated cities in Benton County are shown below in Table 2.1. Benton County?s current (2004) population is thus approximately 80,000. Table 2.1 Benton County Population Data Location 2000 Census Estimate July 1, 2003 Benton County 78,153 79,335 Incorporated Cities Adair Village 536 519 Corvallis 49,322 50,126 Monroe 607 594 Philomath 3,838 4,198 Albany (North)1 6,984 n/a 1 Only North Albany is within Benton County. 2000 Census Data (Census Tract 101) show a population of 6,984 in North Albany and surrounding areas in Benton County. Albany's total population (2003) is about 43,000. The City of Corvallis has more than 60% of Benton County?s total population. Together, the three largest population concentrations (Corvallis, Philomath, and North Albany) contain nearly 80% of the county?s population. The remaining 20% of Benton County?s population is scattered in small communities and in rural areas. 2-2 Historical population data for Benton County since 1900 are shown below in Table 2.2. These long-term data show the steady growth of population in Benton County over the decades. Table 2.2 Benton County Historical Population Data Census Population 1900 6,706 1910 10,663 1920 13,744 1930 16,555 1940 18,629 1950 31,570 1960 39,165 1970 53,776 1980 68,211 1990 70,811 2000 78,153 More detailed population and demographic data for Benton County from the 2000 Census are shown below in Table 2.3, along with similar data for Oregon. The Age and Ethnicity categories in Table 2.3 below intentionally include overlapping subsets of categories for planning purposes. 2-3 Table 2.3 Population Demographics (2000 Census Data) Benton County Oregon Under 5 years 5.1% 6.5% Under 18 years 21.3% 24.7% 18 years and over 78.7% 75.3% 18 years to 65 years 68.4% 62.5% 65 years and over 10.3% 12.8% White 89.2% 86.6% Black or African American 0.8% 1.6% American Indian and Alaska Native 0.8% 1.3% Asian 4.5% 3.0% Native Hawaiian and Pacific Islander 0.2% 0.2% Other or two or more races 4.5% 7.3% Hispanic or Latino (of any race) 4.7% 8.0% English only 90.0% 87.9% Language other than English 10.0% 12.1% Speak English less than very well 4.0% 5.9% Spanish 4.1% 6.8% Other Indo-European languages 2.3% 2.6% Asian and Pacific Island languages 3.1% 2.4% Demographic Data Age Ethnicity of Households Language Spoken at Home For emergency planning purposes, children, elderly adults, the disabled, and people whose primary language is not English are considered special needs populations. Based on these 2000 census data, Benton County has a substantial population of children and elderly adults, along with about 10% of the population whose primary language is not English. As shown in Table 2.2 below, about 21% of the population is children less than 18 years old, while about 10% are adults over 65 years old. The Census website (www.census.gov) has a vast amount of demographic data for Benton County and for the individual cities within Benton County. See the website for additional demographic data, including school enrollment, educational levels, disability status, and other categories of demographic data useful for planning purposes. 2.3 Employment and Economics In the earliest years, the economy of Benton County was largely agrarian; wheat was the first commercial crop in the Willamette Valley. Industrialization began in the 1850s with the construction of millraces to provide waterpower for flourmills, lumber mills, and later for woolen mills and electricity. In the earliest years, the Willamette River was the major transportation artery for the region. In the 1870s, development of the Willamette 2-4 Valley accelerated when the railroad from California reached Eugene and Albany; the railroad reached Corvallis in the 1880s. Through the mid-20th century, the lumber industry was a very important segment of the local economy. However, by the 1990s, the lumber industry had declined in importance, with economic growth in new sectors, including the high-tech sector. The major employment categories in Benton County are government (Federal, State, County, and the Cities), education (OSU and school districts), high technology (Hewlett-Packard and others), medical care (Good Samaritan Hospital), wood products, and others. Data for the largest employers in Benton County are shown below in Table 2.3. These data are representative, although specific numbers for various employers will change over time. Table 2.3 Largest Employers in Benton County1 Private Sector Employees Public Sector Employees Hewlett Packard 4,200 Oregon State University 8,756 Good Samaritan Hospital 1,400 Corvallis School District 734 Corvallis Clinic 570 City of Corvallis 420 Summit Information Systems 460 Benton County 385 CH2M Hill 420 Suislaw National Forest 150 ATS Systems Oregon 220 US Post Office 128 Evanite Fiber Corp. 176 Greenberry Industries 175 Stahlbush Island Farms 170 Winco Foods 150 OSU Federal Credit Union 150 Georgia-Pacific Corp. 140 GE Interlogic/Kalatel, Inc. 130 Agilent Tech. 100 1 September 2002 Data As shown above, the largest employers include OSU, Hewlett-Packard, Good Samaritan Hospital, Corvallis School District, Corvallis Clinic, Summit Information Systems, City of Corvallis, CH2M Hill, and Benton County, all of who have over 300 employees. 2-5 Selected economic data for Benton County from the 2000 Census are summarized below in Table 2.4. Corresponding data for Oregon are also shown for reference. Table 2.4 Selected Economic Data Benton County Oregon Population 16 years and older 63,608 3,472,867 In labor force 63.6% 65.2% Employed 63.4% 61.0% Unemployed 3.1% 4.2% Not in labor force 36.4% 34.8% Drove alone 70.7% 73.2% Carpooled 10.4% 12.2% Public transportation 1.6% 4.2% Walked 7.7% 3.6% Other means (includes bicycles) 5.2% 1.9% Worked at home 4.4% 5.0% Homeownership rate 57.3% 64.3% Housing units in multi-unit structures 29.8% 23.1% Median household income $41,897 $40,916 Per capita money income $21,868 $20,940 Families below poverty level 6.8% 7.9 with children under 18 years 9.9% 12.4 with children under 5 years 13.5% 16.6 Incomes and poverty levels Demographic Data Commuting to work Housing Data The Census website (www.census.gov) has a vast amount of other economic/ demographic data for Benton County and for the individual cities within Benton County. See the Census website for additional economic/demographic data, including employment breakdowns by occupation and industry, and detailed income data. 2-6 2.4 Housing in Benton County Housing demographic data for Benton County from the 2000 Census are summarized below in Table 2.5. Table 2.5 Housing Data Demographic Data Benton County Oregon Total housing units 31,980 1,452,709 Occupied units 30,145 1,333,723 Vacant units 1,835 118,986 Vacany percentage 5.7% 8.2% Owner-occupied units 54.0% 53.5% Renter-occupied units 40.3% 38.2% For Benton County, the percentage of owner-occupied units is slightly lower than for Oregon as a whole. The age distribution of Benton County?s housing stock is shown below in Table 2.6. Age of the housing stock is relevant for mitigation planning purposes because older construction is much less likely to conform to current building code requirements for fire safety and earthquake safety and less likely to conform to current flood plain management regulations. For example, about 25% of Benton County?s housing stock was built before 1960, with nearly 10% built before 1940. Table 2.6 Benton County Housing Stock by Year Built Year Built Percent 1990 - March 2000 19.4% 1980-1989 9.7% 1970-1979 30.0% 1960-1969 14.8% 1940-1959 16.7% 1939 or earlier 9.4% 2.5 Land and Development The overall pattern of land use and development in Benton County is shown below in Figure 2.7. Benton County Zoning Map 2-7 Figure 2.7. Benton County Zoning Map The vast majority of Benton County is forest, with much smaller areas of agricultural or agricultural/forest lands. Cities and rural residential areas are heavily concentrated along the rivers (Willamette River and Marys River) in the eastern part of the County 2-8 2.6 Regulatory Context: Overview Oregon land use laws require land outside Urban Growth Boundaries (UGBs) to be protected for farm, forest, and aggregate resource values. For the most part, this law limits the amount of development in the rural areas. However, the land use designation can change from resource protection in one of two ways: ? The requested change could qualify as an exception to Statewide Planning Goals, in which case the county must demonstrate to the State that the change meets requirements for an exception. These lands, known as exception lands, are predominantly designated for residential use. ? Resource land can also be converted to non-resource use when it can be demonstrated to Benton County that the land is no longer suitable for farm or forest production. Local and state policies currently direct growth away from rural lands into UGBs and, to a lesser extent, into rural communities. Over the next 50 years, emerging telecommunications services may affect the rural economy, enhancing the capacity of residents in rural areas to access information and deliver services from remote locations. Pressure for rural development may come from people seeking a rural lifestyle, especially workers in the information economy with remote service capacity and retirees who do not have commuting needs. If development follows historical development trends, urban areas will expand their UGBs, rural unincorporated communities will continue to grow, and overall rural residential density will increase slightly with the bulk of rural lands kept in farm and forest use. The existing pattern of development in the rural areas, that of radiating out from the urban areas along rivers and streams is likely to continue. Most of the ?easy to develop? land is already developed, in general leaving more constrained land such as land in the floodplains or on steep slopes to be developed in the future, perhaps increasing the rate at which development occurs in natural hazard areas. 2.7 Regulatory Context: Oregon Statewide Planning Goal 7 Oregon State Planning Overview Since 1973, Oregon has maintained a strong statewide program for land use planning. The foundation of that program is a set of 19 statewide planning goals that express the state's policies on land use and on related topics, such as citizen involvement, land use planning, and natural resources. 2-9 Most of the goals are accompanied by "guidelines," which are suggestions about how a goal may be applied. Oregon's statewide goals are achieved through local comprehensive planning. State law requires each city and county to adopt a comprehensive plan and the zoning and land-division ordinances needed to put the plan into effect. The local comprehensive plans must be consistent with the statewide planning goals. The state?s Land Conservation and Development Commission (LCDC) review plans for such consistency. When LCDC officially approves a local government's plan, the plan is said to be "acknowledged." It then becomes the controlling document for land use in the area covered by that plan. Goal 7 Goal 7: Areas Subject to Natural Disasters and Hazards has the overriding purpose to ?protect people and property from natural hazards?. Goal 7 requires local governments to adopt comprehensive plans (inventories, policies and implementing measures) to reduce risk to people and property from natural hazards. Natural hazards include floods, landslides, earthquakes, tsunamis, coastal erosion, and wildfires. To comply with Goal 7, local governments are required to respond to new hazard inventory information from federal or state agencies. The local government must evaluate the hazard risk and assess the: a. Frequency, severity, and location of the hazard; b. Effects of the hazard on existing and future development; c. Potential for development in the hazard area to increase the frequency and severity of the hazard; and d. Types and intensities of land use to be allowed in the hazard area. Local governments must adopt or amend comprehensive plan policies and implementing measures to avoid development in hazard areas where the risk cannot be mitigated. In addition, the siting of essential facilities, major structures, hazardous facilities and special occupancy structures should be prohibited in hazard areas where the risk to public safety cannot be mitigated. The state recognizes compliance with Goal 7 for coastal and riverine flood hazards by adopting and implementing local floodplain regulations that meet the minimum National Flood Insurance Program (NFIP) requirements. Goal 7 provides local jurisdictions with the following guidelines for planning and implementation: Planning 1. In adopting plan policies and implementing measures for protection from natural hazards local governments should consider: 2-10 a. The benefits of maintaining natural hazard areas as open space, recreation, and other low density uses; b. The beneficial effects that natural hazards can have on natural resources and the environment; and c. The effects of development and mitigation measures in identified hazard areas on the management of natural resources. 2. Local governments should coordinate their land use plans and decisions with emergency preparedness, response, recovery and mitigation programs. Given the numerous waterways and forested lands throughout Benton County, special attention should be given to problems associated with riverbank erosion and potential for wild land/urban interface fires. Implementation 1. Goal 7 guides local governments to give special attention to emergency access when considering development in identified hazard areas. 2. Consider programs to manage storm water runoff as a means to address flood and landslide hazards. 3. Consider non-regulatory approaches to help implement the goal. 4. When reviewing development requests in high hazard areas, require site-specific reports, appropriate for the level and type of hazard. Reports should evaluate the risk to the site as well as the risk the proposed development may pose to other properties. 5. Consider measures exceeding the National Flood Insurance Program. Benton County Compliance With Goal 7 The County evaluates emergency access when considering development. For the most part (with few acceptations) developers are required to build dwellings near the roadway in part to provide easier access for emergency vehicles. Larger development proposals must include a storm water management plan for storm water discharge and development cannot alter an existing waterway. In conformance with NFIP regulations, the County requires that new development in mapped floodplains be at least one foot above the base flood elevation reducing the risk of flood damage. The County improves compliance with Goal 7 by participating in the Community Rating System (CRS) program (see Section 2.9) which exceeds the minimum measures required by the National Flood Insurance Program, including developing a program for storm water maintenance and management. The County could also establish limitations or standards for development in steep slope areas. 2-11 2.9 Community Rating System Jurisdictions that regulate new development in their floodplains are able to join the National Flood Insurance Program (NFIP). In return, the NFIP provides federally backed flood insurance for properties in participating areas. Benton County participates in the NFIP program and over flood 950 insurance policies are held within Benton County (including the cities). The Community Rating System (CRS) is a part of the NFIP. The CRS reduces flood insurance premiums to reflect what a community does above and beyond the NFIP?s minimum standards for floodplain regulation. The objective of the CRS is to reward communities for what they are doing, as well as to provide an incentive for new flood protection activities. The reduction in flood insurance premium rates is provided according to a jurisdiction?s CRS classification, which is dependent upon the number of points awarded the jurisdictions for flood reduction activities implemented. To apply, a jurisdiction submits documentation that shows what it is doing and that its activities deserve at least 500 points. By participating in the CRS program, a jurisdiction not only reduces the risk of loss due to flood damage but policyholders gain up to a 45 percent reduction in flood insurance premiums. Community participation in the CRS is voluntary and Benton County does participate in this program, with a rating of 7. There are 18 floodplain management activities credited by the CRS organized under four series: 1. Public Information, 2. Mapping and Regulations, 3. Flood Damage Reduction, and 4. Flood Preparedness. All but two of the 18 management activities are optional. The two required activities are elevation certificate and repetitive loss requirements. Following are the 18 activities from which a jurisdiction can receive CRS credits. Included also is a brief assessment summary for land outside the urban growth boundaries, of what the County is currently doing that meets or does not meet the CRS activity requirements. 2.10 Regulatory Context: Summary Comments Sections 2.6 to 2.9 above reviewed regulatory programs and issues related to hazard mitigation planning. The state land use planning requirements, Goal 7, the Benton Code provisions and the CRS regulations are all regulatory programs. That is, these programs impose legal requirements and restrictions on development that are intended to provide for public safety and to minimize the future impacts of disaster events on Benton County. In contrast, this Hazard Mitigation Plan is not a regulatory document. That is, a Hazard Mitigation Plan is intended to educate the public about hazards and to encourage 2-12 prudent practices but it does not mandate practices or regulate development. However, a Hazard Mitigation Plan is closely related so some regulatory processes in the sense that greater awareness about and better data on hazards may subsequently lead to changes in regulations. An important objective of developing a Hazard Mitigation Plan is to start the long-term process of acquiring better data on hazards, vulnerability and risk in Benton County. Acquiring better data may eventually lead to more regulation of identified high hazard areas. However, better data with higher spatial resolution may also result in reclassifying areas tentatively mapped as being in potential hazard areas as, in fact, not being in hazard areas. For example, the spatial resolution of mapping of potential landslide areas or areas subject to liquefaction in earthquakes is generally low. More refined mapped of such hazards is likely to reduce the areas designated as being potentially subject to these hazards. 2-13 This Page Left Blank 2-14 3.0 Public Process 3.1 Overview Benton County has a strong history of involving citizens and community partners in many of its planning activities. The Board of Commissioners maintains 21 citizen advisory boards that provide input and direction for topics ranging from waste disposal to roads to libraries. One board, the Planning Commission has been active during the development of the Pre-Disaster Mitigation plan. Public participation allows a range of public interests to participate and express their ideas, thoughts, and opinions on matters that are important to their way of life. As government stewards of the people, Benton County Government has an obligation to solicit and receive the view of its citizenry. Additionally, the State of Oregon and FEMA have requirements to receive public input during the development of Land Use Plans and flood mitigation plans, respectively. The involvement of the public has resulted in a Pre-Disaster Mitigation plan that represents the concerns and ideas of individuals, organizations, and other agencies and reflects these concerns and ideas in the action items. 3.2 Steering Committee A steering committee was formed from agencies that had a vested interest in developing a Pre-Disaster Mitigation plan. The members represent other agencies that are tasked with similar activities as stated in this plan?s goals and objectives. The stakeholders shared their perspectives that they have received from conducting their own public process and the result is a more balanced and comprehensive plan. The following were agencies that participated in the Benton County Pre-Disaster Mitigation Plan Steering Committee: Participant Organization Ed Barlow-Pietrick CH2M Hill Gordon Brown Benton County Health Department Kevin Bryan ODOT Ken Elwer City of Philomath Police Department Roy Emery City of Corvallis - Fire Department Kathy Gager City of Corvallis - Community Development Peter Idema Benton County - Public Works Steve LeBoeuf Oregon State University Mike Bamberger Benton County Emergency Management Peggy Peirson Benton County Emergency Management Steve Rogers City of Corvallis - PW Rick Smith Monroe Rural Fire Protection District 3-1 Dale Staib Philomath Rural Fire Protection District/BCFDB Laurie Starha Benton County - Public Works Bob Vanderford Good Samaritan Regional Medical Center Periodic meetings were held to aid in the timely development of the plan. The original timeline was delayed and ultimately dismissed as other activities occurred. The major activities that affected the original timeline were a Presidential Disaster Winter Storm, a massive abducted person search operation, and the contractor bidding process. Ultimately, a new timeline that integrated contract work and continual work by the steering committee was developed and the public process continued until completion. August 28, 2003 ? Steering Committee The Benton County Emergency Manager met with the Benton County Emergency Council sub-committee Plans, Training, and Exercise to inform them of the PDM, its requirements and to seek their guidance in developing the Steering Committee. The group then conducted a goal and objective review of various existing documents to develop a framework to develop Pre-Disaster Mitigation Plan goals and objectives. This sub-committee consists of members that would eventually form the PDM Steering Committee. This sub-committee meets monthly and updates each other on projects/plans/training and uses this meeting to merge activities so a more integrated product is developed. October 23, 2003 ? Steering Committee Mike Bamberger presented the PDM concept and program to the Quarterly Meeting of the community Benton County Emergency Management Council. The 20 representatives voted to support the program and several volunteered to become part of the Steering Committee. November 18, 2003 ? Steering Committee A Kickoff meeting was held with the steering committee members (listed previously) plus representatives from the special districts in Benton County. Those members of the special districts that could not attend were notified of the results of the meeting via mail and how they would be asked to participate in the later portions of the process, as the plan was readied for public comment. A presentation about the requirement and what it entailed was given, a work schedule was decided upon, and a timeline of meetings was developed. The members of the steering committee were given samples of goals and objectives and asked to research similar documents within their jurisdictions to help develop the goals at the next meeting. 3-2 December 11, 2003 ? Steering Committee The steering committee met and developed a Vision, Mission and Goals for the PDM. Additionally, they identified other people they would like to see participate in the process ? whether as committee members or as consultants. The committee also worked through a process that resulted in identifying the top hazards facing Benton County and its communities. The committee was tasked to come back to the next meeting with research on what existing studies, GIS layers, or information existed on the hazards that were determined. Additionally, the committee asked Mike Bamberger to draft some Objectives for their review and discussion at the next work session. March 11, 2004 ? Steering Committee The group met and reviewed the work conducted in December, since the long interval between meetings occurred due to a Presidential Declaration for the Dec/Jan snowstorm. The committee also reviewed and modified the objectives that had been developed and approved of the final Vision, Mission, Goals, and Objectives for the plan. The group approved the request from Mike Bamberger to seek a contractor to help with the development of the plan, funded by the Benton County Emergency Management Office. Finally, a compilation of all information regarding the identified hazards was presented as a reference. Bamberger stated that he had a volunteer that was conducting research in historical archives and documenting as much data as could be found. Bamberger then stated he had enough guidance and materials to develop a scope of work, conduct a contract process, and begin working on the plan. As chapters became completed, the steering committee would be emailed the documents for review. After an initial draft of all the chapters was completed, the committee would meet again and begin the public input process to develop the future work items of the plan. February 24, 2005 ? Public Meeting #1 A public meeting was held with the community Benton County Emergency Management Council. Bamberger presented the Pre-Disaster Mitigation Plan draft, reviewed the mission, vision, goals, and objectives of the plan, and then summarized each hazard chapter. 3-3 A facilitated session was held to identify mitigation projects and efforts that would support the implementation of the plan. From this discussion, several ideas were gathered and incorporated into the short- and long-term action plan list. A summary of the meeting and ideas generated are attached at the end of this chapter. July 26, 2005 Steering Committee #4 and separate Special District Meeting The steering committee met to review the draft plan and finalize the Mitigation Plan Action Item list. Additionally, the committee decided on the formation of the Pre-Disaster Mitigation Committee, which will meet quarterly to continue the plan?s work items. Finally, the Cities of Corvallis and Philomath discussed how the County plan could be used to facilitate their plan. With most of the research and documentation within the County plan, annexes of city specific action items and addressing other city specific items should meet the FEMA requirements. +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ A following meeting was held with Special District Representatives to detail the requirements of having a mitigation plan for their district. The process of how the County mitigation plan was created and input solicited was described. The Special District representatives reviewed the Vision, Mission, Objectives and the Action Item list and provided input and comments about the projects identified within. The Districts agreed that the plan captured their risks and that the Action List items would help them in their planning and mitigation efforts. Districts were encouraged to return to their board members and begin a mini- planning session to identify specific risks and solutions that the Pre-Disaster Mitigation Grant program could assist with. Additionally, the special districts would have to complete a district specific annex and receive approval from their board and FEMA to be eligible for grant application. 3-4 Pre-Disaster Mitigation Plan Public Meeting #1 ? Benton County Emergency Management Council Meeting February 24, 2005 Attending: Michael Bamberger Benton County Emergency Management Ed Barlow-Pieterick CH2M Hill Gordon Brown Benton County Environmental Health Roy Emery Corvallis Fire Department Kevin Harding Hewlett Packard J Brian Leeper American Red Cross Joe Lewis Philomath Fire and Rescue Peggy Peirson Benton County Emergency Management James Ramseyer Consumers Power Inc Jack Rogers Oregon State University, Department of Public Safety Jerry Smith City of Corvallis Public Works Laurie Starha Benton County Public Works Ann Steeves Good Samaritan Regional Medical Center Dan Sundseth US Department of Agriculture Karen Selander Corvallis School District Dale Staib Philomath Fire and Rescue Doug Van Pelt Citizen, BCEMC Chairperson The public session was held in conjunction with the Benton County Emergency Management Quarterly meeting. Emergency Manger Mike Bamberger presented the Pre-Disaster Mitigation Plan to the participants and then conducted group review/brainstorming sessions. The participants agreed with the proposed long term/short term action items and felt the items were consistent with previous Project Impact work and other efforts within the community. Additionally, the participants focused on how to keep the plan alive and working, through a focus on increased public education and awareness. A discussion was held regarding BCEMC adopt shepherding of the PDM? Not unlike Project Impact. Seems like a fitting spot for community-wide PDM, Steering Committee. Further thought and analysis were needed before the Council would consider adopting the PDM as an undertaking by the group. Attach 3-1 Several ideas that came from the session were: ? Keep hazards/vulnerability top of mind without ?Armageddon- style?/sensationalism approach. Assertive, proactive, planned media/public ed component? ?Teachable moments.? ? Highlight mitigation applied, practices. Campaign. ? Insert in utility bills? Tip of the month idea? o CPI Ruralite? o USDA Publication o Email distribution lists o ?The City? newsletter o Regular column w/GT, DH o Peggy?s email lists o PPL, NW Natural, Water Bills, Corvallis Disposal o Cable Public Access or TV Guide Channel? (crawler) o Sponsor for direct-mailing, topic specific o Piggy-back on other mailings (i.e., NFIP/CRS mailing) o Property tax bill, ?protect YOUR investment? o Landlords/renters o Faith community ? Revamp Benton County Emergency Management website? ? Employer/employee preparedness campaigns o Target critical services workers o Presentations-Peggy has ready ? Standardized messages, all singing from the same sheet of music? ? It is the responsible thing for citizens to do, responsibility, contribution to community resilience, all-hazards effort, advocate w/o scaring ? Get message and the capability to do something about it combined ? at the same time. Advertising/preparedness campaigns at hardware store, etc. ? Seasonal campaigns, i.e., ?squirrel? and fall preparedness? Possible Projects? ? Fuel load study (wildfire) ? Building code/development restrictions/requirements ? Note: possible drought year coming?. (teachable moment) ? Flooding o Repetitive flood loss properties identified o At risk properties identified o At risk properties/population targeted with information ? Winter storms o Utility, power, life-line disruptions o Prevention, target hardening (tree-trimming, burying lines) ? publicize when these efforts are undertaken Attach 3-2 o Preparedness o Landslides/vulnerability along Hwy 20/22 and isolation/access effect ? Special Needs Population ? identification, reaching ? ?Victimology? ? assessment of affected populations and focus campaigns on them. Organizations already have history of vulnerable (utilities, public works, etc.) o ARC proposed project? Not funded by United Way. Also a critical HRSA benchmark. ? Earthquake ? non-structural seismic mitigation ? promote and highlight organizations who do this. Attach 3-3 Attach 3-4 July 26, 2005 1430-1530 Pre-Disaster Mitigation Plan Special Districts MINUTES Present: Mike Bamberger Benton County Emergency Manager Peggy Peirson Benton County Emergency Coordinator Ken Goettel Contractor Curtis Day (for Bardon Maginnis) Marys River Estates Road District Brooke Collison Country Estates Road District Ann Adams Country Estates Road District Harold Haskins McDonald Forest Estates Road District Michael Drost Westwood Hills Road District Joe Heaney Vineyard Mountain Road District Introductions Explanation of handouts/DRAFT Plan Ken Goettel Chapter layout Chapter 2 Review of regulatory context Chapter 4 Review of Mission, Objective, Goals Review of Task List Verification of tasks Agreement on action agencies Addition/Subtraction of tasks Review and input from Special Districts How to customize/make applicable the County Plan for a special district plan List of partners involved with PDM Plan Development S = Steering Committee I = Invited A = Attend Comm Agency First Name Last Name 8/28/03 BCEMC - Sub Comm 10/23/03 BCEMC Meeting - 1a 11/18/03 Kickoff - 1b 12/11/2003 Mission/Vis 3/11/04 Session 3 07/26/2005 Session 4 7/26/05 Spec Dist S Benton County - Public Works Peter Idema I I I A S Benton County - Public Works Laurie Starha A A A I S Benton County Emergency Management Mike Bamberger A A A A A A S Benton County Emergency Management Peggy Peirson A A A I A S Benton County Health Department Gordon Brown A A A A I S CH2M Hill Ed Barlow-Pietrick A A A A I S City of Corvallis - Community Development Kathy Gager A A A S City of Corvallis - Fire Department Roy Emery I I A I I S City of Corvallis - PW Steve Rogers I A A A S City of Monroe I* I I I S City of Philomath Police Department Ken Elwer I I A A A A S Good Samaritan Regional Medical Center Bob Vanderford I I A A I S Monroe Rural Fire Protection District Rick Smith I A I I I S ODOT Kevin Bryan A A I I S Oregon State University Steve LeBoeuf A I A A A I S Philomath Rural Fire Protection District/BCFDB Dale Staib I I I* I A I Accountable Behavioral Health All I Adair Rural Fire Protection District Chuck Harris I I Albany Fire Department Kevin Kreitman I Alpine County Service District Chris Bielenberg I I Alsea Cemetery Maintenance District I I Alsea County Service District Chris Bielenberg I I Alsea Rural Fire Protection District Chuck Carver I I American Red Cross A Attach 3-5 List of partners involved with PDM Plan Development Comm S = Steering Committee I = Invited A = Attend 8/28/03 10/23/03 7/26/05 Spec Dist BCEMC - Agency First Name Last Name Sub Comm BCEMC 11/18/03 12/11/2003 3/11/04 07/26/2005 Kickoff - 1b Mission/Vis Session 3 Session 4 Meeting - 1a ARES Al Ward I ARES Lew Williams I Benton County - Commissioner Linda Modrell A Benton County - Public Works Roger Irvin I I Benton County Emergency Management Council Doug Van Pelt A Benton County Health Department Bill Emminger I Benton County Health Department Tom Eversole I Benton County Health Department Craig Hogue A Benton County Library Service District I Benton County School District 001J Terry Mahler I Benton County School District 007J Del Corsey I Benton County School District 017J Rod Harvey I Benton County School District 017J Tom Ries I I I Benton County School District 509J Gregg Griffin A Benton County School District 509J Karen Selander I I Benton County School District 509J Fred Wright I I Benton Soil and Water Conservation District I Blodgett Summit Rural Fire Protection District Ed Young I I Brownly Marshall Road District I I Cascade View County Service District Chris Bielenberg I I Chinook Drive Special Road District Jay Sorgen A I Citizen John Butterworth I Citizen Mary Carper I City of Adair Village Jim Minard I Attach 3-6 List of partners involved with PDM Plan Development Comm S = Steering Committee I = Invited A = Attend 8/28/03 10/23/03 7/26/05 Spec Dist BCEMC - Agency First Name Last Name Sub Comm BCEMC 11/18/03 12/11/2003 3/11/04 07/26/2005 Kickoff - 1b Mission/Vis Session 3 Session 4 Meeting - 1a City of Corvallis Ken Gibb I City of Corvallis - Airport Buck Taylor I I City of Corvallis - Community Development Kelly Schlesener City of Corvallis - Police Department Gary Boldizsar I City of Corvallis - Police Department Jon Sassaman I A City of Corvallis - PW Tom Penpraze A City of Corvallis - PW - Electronics Jim Mitchell I City of Philomath - City Manager Randy Kugler I I City of Philomath - Public Works Beau Vencil I I Community Service Consortium Tom Clancy-Burns I Community Service Consortium Mike Gibson I Consumers Power James Ramseyer A Corvallis Clinic Jeff Brandt I Corvallis Rural Fire Protection District Dan Campbell I Corvallis Rural Fire Protection District George Mears I Country Estates Road District Ann Adams I A Evanite Fiber Corp Jay Doyle I Good Samaritan Regional Medical Center Kathy Hale I Greenberry Irrigation District 3 I Hewlett Packard David Gramlich I Hewlett Packard Kevin Harding I A Hewlett Packard Sharon Pleu A Hoskins-Kings Valley Rural Fire Protection District Dave Evans I Hospital Facility Authority of Benton County Rib Stevens A League of Women Voters Kathryn Conner I Attach 3-7 List of partners involved with PDM Plan Development Comm S = Steering Committee I = Invited A = Attend 8/28/03 10/23/03 7/26/05 Spec Dist BCEMC - Agency First Name Last Name Sub Comm BCEMC 11/18/03 12/11/2003 3/11/04 07/26/2005 Kickoff - 1b Mission/Vis Session 3 Session 4 Meeting - 1a Linn County Emergency Management Jim Howell I Love Inc Wilma Van Schlevyn A Mary's River Estates Road District Bardon Maginnis I A McDonald Forest Estates Special Road District Harold Haskins A A North "F" Street Road District I I North Albany County Service District Chris Bielenberg I I North Albany Rural Fire Protection District I I Oakwood Heights Road District Jeff Hansen I I Oregon Cascades West Council of Government I Oregon State University Jim Lloyd I Palestine Rural Fire Protection District No. 6 I Philomath Urban Renewal Agency Randy Kugler I Pioneer Telephone Dick Hubbard I Pioneer Village Service District Chris Bielenberg I Ridgewood Development Road District Robert Collier I I Rosewood Estates Road District I I Salvation Army Lee Corson I USDA Dan Sundseth A Vineyard Mountain Parks and Recreation District I I Vineyard Mountain Road District Joe Heaney I A Westwood Hills Road District Michael Drost I A Country Estates Road District Brooke Collison A Attach 3-8 4.0 Mitigation Plan Mission Statement, Goals, Objectives and Action Items 4.1 Overview The overall purpose of the Benton County Hazard Mitigation Plan is to reduce the impacts of future natural or human-caused disasters on the people and communities of Benton County. Benton County has a vision of building a safer, hazard resilient, and more sustainable community, by reducing the vulnerability to disasters and enhancing the capability to respond effectively to and recover quickly from future disasters. Completely eliminating the risk of future disasters in Benton County is neither technologically possible nor economically feasible. However, substantially reducing the negative impacts of future disasters is achievable with the adoption of this pragmatic Hazard Mitigation Plan and ongoing implementation of risk reducing action items. Incorporating risk reduction strategies and action items into the county?s existing programs and decision making processes will facilitate moving Benton County toward a safer and more disaster resistant future. To proactively facilitate and support countywide policies, practices, and programs that will make Benton County more disaster resistant and disaster resilient, Benton County must take steps and actions to: ? Protect life safety, ? Reduce property damage, ? Minimize economic losses and disruption, and ? Shorten the recovery period from future disasters. In addition, the Benton County Hazard Mitigation Plan is intended to meet or contribute towards meeting various regulatory requirements, including: 1. FEMA?s (Federal Emergency Management Agency) mitigation planning requirements so that Benton County remains eligible for pre- and post- disaster mitigation funding from FEMA, 2. FEMA?s Flood Insurance Program?s Community Rating System guidelines, to help minimize future flood insurance rates in Benton County, 3. Oregon Emergency Management?s mitigation planning evaluation criteria, and 4. Oregon?s Goal 7 natural hazard planning guidelines. Meeting these regulatory requirements is an essential step to facilitate implementation of mitigation measures and in making progress towards achieving the primary mission, goals and objectives summarized below. 4-1 The Benton County Hazard Mitigation Plan is based on a four-step framework that is designed to help focus attention and action on successful mitigation strategies: Mission Statement, Goals, Objectives and Action Items. ? Mission Statement. The Mission Statement states the purpose and defines the primary function of the Benton County Hazard Mitigation Plan. The Mission Statement is an action-oriented summary that answers the question ?Why develop a hazard mitigation plan?? ? Goals. Goals identify priorities and specify how Benton County intends to work toward reducing the risks from natural and human-caused hazards. The Goals represent the guiding principles toward which the County?s efforts are directed. Goals provide focus for the more specific issues, recommendations and actions addressed in Objectives and Action Items. ? Objectives. Each Goal has Objectives that specify the directions, methods, processes, or steps necessary to accomplish the plan?s Goals. Objectives lead directly to specific Action Items. ? Action Items. Action items are specific well-defined activities or projects that work to reduce risk. That is, the Action Items represent the steps necessary to achieve the Mission Statement, Goals and Objectives. 4.2 Mission Statement The mission of the Benton County Hazard Mitigation Plan is to: Promote sound polices and programs designed to protect citizens, critical facilities, infrastructure, public and private property, economic vitality, and the environment from natural and human- caused hazards. 4.3 Mitigation Plan Goals and Objectives Mitigation plan goals and objectives guide the direction of future policies and activities aimed at reducing risk and preventing loss from disaster events. The goals and objectives listed here serve as guideposts and checklists as agencies, organizations, and individuals begin implementing mitigation action items in Benton County. Benton County?s mitigation plan goals and objectives are based on the goals established by the State of Oregon Natural Hazards Mitigation Plan. However, the specific priorities, emphasis and language are Benton County?s. These goals were developed with extensive input and priority setting by agencies, the mitigation plan steering committee, stakeholders and citizens from throughout Benton County. 4-2 Goal 1: Reduce the Threat to Life Safety Objectives: ? Enhance life safety by minimizing the potential for deaths and injuries in future disaster events. ? Improve community warning and notification methods ? Evaluate jurisdictional guidelines, codes, policies, and permitting processes to address hazard mitigation Goal 2: Protect Critical Facilities and Enhance Emergency and Essential Services Objectives: ? Implement activities or projects to protect critical facilities and infrastructure ? Seek opportunities to enhance, protect, and integrate emergency and essential services. ? Strengthen emergency operations plans and procedures by increasing collaboration and coordination among public agencies, non-profit organizations, business, and industry. Goal 3: Reduce the Threat to Property Objectives: ? Seek opportunities to protect, enhance and integrate emergency and essential services with land use planning and natural resource management. ? Strengthen emergency operations plans and procedures by increasing collaboration and coordination among public agencies, non-profit organizations, business, industry and the citizens of Benton County. ? Preserve and rehabilitate natural systems to serve as natural hazard mitigation functions (i.e., floodplains, watersheds, and urban interfaces) Goal 4: Create a Disaster Resistant and Disaster-Resilient Economy Objectives: ? Develop and implement activities to protect economic well-being and vitality while reducing economic hardship in post disaster situations. ? Reduce insurance losses and repetitive claims for chronic hazard events ? Work with State and Federal Partners to reduce short-term and long-term recovery and reconstruction costs. ? Work with local organization, such as Benton Emergency Planning Association (BEPA). ? Expedite pre-disaster and post-disaster grants and program funding. 4-3 4-4 Goal 5: Increase Public Awareness, Education, Outreach, and Partnerships Objectives: ? Coordinate and collaborate, where possible, risk reduction outreach efforts with the Oregon Partners for Disaster Resistance & Resilience and other public and private organizations. ? Develop and implement risk reduction education programs to increase awareness among citizens, local, county, and regional agencies, non- profit organizations, business, and industry. ? Promote insurance coverage for catastrophic hazards ? Strengthen communication and coordinate participation in and between public agencies, citizens, nonprofit organizations, business, and industry. ? Develop relationships for planning and mitigation activities that are inclusive of multiple areas (i.e., communication and environment and transportation) 4.3 Benton County Hazard Mitigation Plan Action Items The Mission Statement, Goals and Objectives for Benton County, as outlined above, are achieved via implementation of specific mitigation action items. Action items may include refinement of policies, data collection to better characterize hazards or risk, education, outreach or partnership building activities, as well as specific engineering or construction measures to reduce risk from one or more hazards at specific locations within Benton County. Individual action items may address a single hazard (such as flood, earthquake, or wildland/urban interface fires) or they may address two or more hazards concurrently. Action items identified and prioritized during the development of the Benton County Hazard Mitigation Plan are summarized in the following tables. The first group of action items is for multi-hazard items that address more than one hazard, followed by groups of action items for each of the ten hazards addressed in this plan (as addressed in Chapters 6 to 15). Mitigation Plan Goals Addressed Hazard Action Item Coordinating Organizations Timeline Life Safe Critical Facilities and Eme Services Protect Property Disaster Resilient Econo Public Education, Outr Partner Multi-Hazard Mitigation Action Items Short-Term #1 Establish a formal role for the Benton County Hazard Steering Planning Committee to develop a sustainable process to encourage, implement, monitor, and evaluate countywide mitigation actions Benton County Hazard Mitigation Steering Committee Ongoing X X X X X Short-Term #2 Identify and pursue funding opportunities to implement mitigation actions Benton County Hazard Mitigation Steering Committee Ongoing X X X X X Short-Term #3 Develop public and private sector partnerships to foster hazard mitigation activities Benton County Hazard Mitigation Steering Committee Ongoing X X X X X Short-Term #4 Develop detailed inventories of at-risk buildings and infrastructure and prioritize mitigation actions, especially for critical facilities Benton County GIS and Emergency Management 1-2 Years X X X X Long-Term #1 Develop education programs aimed at mitigating the risk posed by hazards Benton County Hazard Mitigation Steering Committee, BC Em Mgt Council Ongoing X X X X X Long-Term #2 Integrate the Mitigation Plan findings into planning and regulatory documents and programs Benton County Hazard Mitigation Steering Committee and Community Development, cities Ongoing X X X X X Long-Term #3 Integrate hazard, vulnerability and risk Mitigation Plan findings into enhanced Emergency Operations planning. Benton County Emergency Management Ongoing X X X X X Long-Term #4 Countywide GIS mapping: add data layers for high risk areas for each natural hazard Benton County GIS and Emergency Management, cities Ongoing X X X X X 4-5 Mitigation Plan Goals Addressed Hazard Action Item Coordinating Organizations Timeline Life Safe Critical Facilities and Eme Services Protect Property Disaster Resilient Econo Public Education, Outr Partner Flood Mitigation Action Items: Within FEMA-Mapped Floodplains Short-Term #1 Complete inventory of critical facilities within 100- year and 500-year floodplains, with GIS mapping if possible Benton County GIS, cities, special districts Ongoing X X X X Short-Term #2 Complete inventory of residential and commercial buildings within 100-year and 500-year floodplains, with GIS mapping if possible Benton County GIS, cities, special districts Ongoing X X X Short-Term #3 Consult with property owners and explore mitigation actions for any Benton County properties on FEMA's national repetitive loss list Benton County Hazard Mitigation Steering Committee / Community Development / BC Em Mgt 1 year X X X X Long-Term #1 Survey elevation data for critical facilities, residential buildings and commercial buildings within the 100-year floodplain and establish flood mitigation priorities Local emergency service agencies, Benton County Hazard Mitigation Steering Committee 2-5 years X X X X X Long-Term #2 For critical facilities within the 100-year floodplain and for other structures deep within the 100-year floodplain explore mitigation options with property owners and implement mitigation measures Local emergency service agencies, Benton County Hazard Mitigation Steering Committee 2-10 years X X X X X 4-6 Mitigation Plan Goals Addressed Hazard Action Item Coordinating Organizations Timeline Life Safe Critical Facilities and Eme Services Protect Property Disaster Resilient Econo Public Education, Outr Partner Flood Mitigation Action Items: Outside of FEMA-Mapped Floodplains Short-Term #1 Complete the inventory of locations in Benton County subject to frequent storm water flooding Benton County Roads and GIS, cities, special districts Ongoing X X X X X Long-Term #1 For locations with repetitive flooding and significant damages or road closures, determine and implement mitigation measures such as upsizing culverts or storm water drainage ditches Benton County Engineer, Community Development, cities, special districts Ongoing X X X X X 4-7 Mitigation Plan Goals Addressed Hazard Action Item Coordinating Organizations Timeline Life Safe Critical Facilities and Eme Services Protect Property Disaster Resilient Econo Public Education, Outr Partner Winter Storms Mitigation Action Items Short-Term #1 Complete the inventory of locations in Benton County subject to frequent storm water flooding Benton County Roads, GIS, cities Ongoing X X X X X Short-Term #2 Enhance tree-trimming efforts especially for transmission lines and trunk distribution lines. BPA, Consumers Power, PP&L, local PUDs Ongoing X X X X X Short-Term #3 Encourage prudent tree planting (avoid service lines) and safe, professional tree trimming where necessary Community Development Ongoing X X X Short-Term #4 Ensure that all critical facilities in Benton County have backup power and emergency operations plans to deal with power outages Emergency Management, Benton County Facilities, Benton County Hazard Mitigation Steering Committee 1-2 Years X X Long-Term #1 For locations with repetitive flooding and significant damages or road closures, determine and implement mitigation measures such as upsizing culverts or storm water drainage ditches Benton County Roads and Engineer, cities Ongoing X X X X X Long-Term #2 Consider upgrading lines and poles to improve wind/ice loading, under grounding critical lines, and adding interconnect switches to allow alternative feed paths and disconnect switches to minimize outage areas BPA, Consumers Power, PP&L, local PUDs 5 Years X X X X X Long-Term #3 Encourage new developments to include underground power lines Benton County Community Development, cities ongoing X X X X X 4-8 Mitigation Plan Goals Addressed Hazard Action Item Coordinating Organizations Timeline Life Safe Critical Facilities and Emergen Serv Protect Property Disaster Resilient Econo Public Education, Outr Partner Landslide Mitigation Action Items Short-Term #1 Complete the inventory of locations where critical facilities, other buildings and infrastructure are subject to landslides Benton County GIS, cities (public works) 1-2 Years X X X X X Long-Term #1 Consider landslide mitigation actions for slides seriously threatening critical facilities, other buildings or infrastructure Benton County Engineer, Community Development, cities, special districts 5 Years X X X X X Long-Term #2 Limit future development in high landslide potential areas by adopting landslide development practices that minimize landslide potential Benton County Community Development Ongoing X X X X X 4-9 Mitigation Plan Goals Addressed Hazard Action Item Coordinating Organizations Timeline Life Safe Critical Facilities and Emergen Serv Protect Property Disaster Resilient Econo Public Education, Outr Partner Wildland/Urban Interface Fire Mitigation Action Items Short-Term #1 Identify specific parts of Benton County at high risk for urban/wildland urban interface fires because of fuel loading, topography and prevailing construction practices Benton County GIS and Community Development, Benton County Fire Defense Board, fire agencies 1-2 Years X X X X X Short-Term #2 Identify evacuation routes and procedures for high risk areas and educate the public Benton County Fire Defense Board, fire agencies, law enforcement, County Roads, public works Ongoing X X X X Short-Term #3 Develop Community Wildland Fire Protection Plans Benton County Community Development, cities, fire agencies, ODF 1-2 Years X X X X X Short-Term #4 Collect statistics on non-ODF vegetation fires from local fire agencies Benton County Fire Defense Board, GIS 1 year X X X X Short-Term #5 Complete surveys of areas of special concern for Wildland/urban interface firs from remaining l fire agencies in Benton County along the lines of Table 9.5 above Local Fire Departments, Benton County Emergency Services 1 year X X X X Long-Term #1 Encourage fire-safe construction practices for existing and new construction in high risk areas Benton County Community Development, city building departments, fire agencies Ongoing X X X X X 4-10 Mitigation Plan Goals Addressed Hazard Action Item Coordinating Organizations Timeline Life Safe Critical Facilities and Eme Services Protect Property Disaster Resilient Econo Public Education, Outr Partner Earthquake Mitigation Action Items Short-Term #1 Complete inventory of public and commercial buildings that may be particularly vulnerable to earthquake damage Benton County GIS, Community Development, cities, special districts 1-2 Years X X X X X Short-Term #2 Complete inventory of wood-frame residential buildings that may be particularly vulnerable to earthquake damage, including pre-1940s homes and homes with cripple wall foundations. Benton County GIS, Community Development, cities, special districts 1-2 Years X X X X X Short-Term #3 Disseminate FEMA pamphlets to educate homeowners about structural and non-structural retrofitting of vulnerable homes and encourage retrofit Benton County Community Development, Emergency Management, Hazard Mitigation Steering Committee Ongoing X X X X Short-Term #4 Complete seismic vulnerability analysis of important public facilities with significant seismic vulnerabilities County, cities, special districts 1-2 Years X X X X X Long-Term #1 Obtain funding and retrofit important public facilities with significant seismic vulnerabilities County, cities, special districts 10 years X X X X X Long-Term #2 Retrofit bridges that are not seismically adequate for lifeline transportation routes ODOT, County, cities, roads X X X X X 4-11 Mitigation Plan Goals Addressed Hazard Action Item Coordinating Organizations Timeline Life Safe Critical Facilities and Eme Services Protect Property Disaster Resilient Econo Public Education, Outr Partner Volcanic Hazards Mitigation Action Items Short-Term #1 Update public emergency notification procedures for ash fall events CRCC, Benton County Emergency Management 1-2 Years X X X Short-Term #2 Update emergency response planning for ash fall events local emergency services agencies 1-2 Years X X X Short-Term #3 Evaluate capability of water treatment plants to deal with high turbidity from ash falls and upgrade treatment facilities and emergency response plans to deal with ash falls local water agencies 1-2 Years X X X X X Short-Term #4 Evaluate ash impact on storm water drainage system and develop mitigation actions if necessary public works agencies 1-2 Years X X X X 4-12 Mitigation Plan Goals Addressed Hazard Action Item Coordinating Organizations Timeline Life Safe Critical Facilities and Emerg Protect Property Disaster Resilient Econo Public Education, Outr Partner Dam Safety Mitigation Action Items Short-Term #1 Prepare high resolution maps of dam failure inundation areas and update emergency response plans, including public notification and evacuation routes Benton County GIS, Benton County Emergency Management, Corps of Engineers, city building departments 1-2 Years X X X Short-Term #2 Identify dikes and owners and the impact of protected structures Benton County GIS, Benton County Emergency Management, Benton County Public Works, city building departments 2-3 years X X X X Long-Term #2 Encourage the Corps of Engineers to complete seismic vulnerability assessments for dams upstream of heavily populated areas in Benton County and to make seismic improvements as necessary Benton County Hazard Mitigation Steering Committee, US Army Corps of Engineers Ongoing X X X X X Long-Term #3 Evaluate the adequacy of dike systems for both floods and earthquakes and implement mitigation measures if necessary Benton County Public Works, US Army Corps of Engineers Ongoing X X X X X 4-13 Mitigation Plan Goals Addressed Hazard Action Item Coordinating Organizations Timeline Life Safe Critical Facilities and Eme Services Protect Property Disaster Resilient Econo Public Education, Outr Partner Utility and Transportation System Disruption Mitigation Action Items Short-Term #1 Educate and encourage residents to maintain several days of emergency supplies for power outages or road closures Benton County Emergency Management Ongoing X X X Short-Term #2 Review and update emergency response plans for disruptions of utilities or roads local emergency service agencies, CRCC 1-2 Years X X X Short-Term #3 Ensure that all critical facilities in Benton County have backup power and emergency operations plans to deal with power outages Benton County Emergency Management, Benton County Facilities 1-2 Years X X X 4-14 Mitigation Plan Goals Addressed Hazard Action Item Coordinating Organizations Timeline Life Safe Critical Facilities and Eme Services Protect Property Disas Resilient Econo P Education, Outr Partner Hazmat Incident Mitigation Action Items Short-Term #1 Ensure that first responders have readily available site-specific knowledge of hazardous chemical inventories in Benton County local fire and law enforcement agencies 1 year X X X Short-Term #2 Enhance emergency planning, emergency response training and equipment to address hazardous materials incidents. local fire and law enforcement agencies Ongoing X X X Long-Term #1 Modify existing codes to prohibit aggravating or creating a hazard in identified risk areas i.e. HAZMAT storage in a floodplain Community Development Departments 5 years X X X X Long-Term #2 Evaluate and assist with upgrade seismic bracing/anchoring for storage of large quantities of hazardous materials and for all Extremely Hazardous Material storage location Benton County Public Works (for county materials), city public works (for city materials), local industry, County Engineer, Benton County Emergency Management 10 years X X X X 4-15 Mitigation Plan Goals Addressed Hazard Action Item Coordinating Organizations Timeline Life Safe Critical Facilities and Emerg Protect Property Disaster Resilient Econo Public Education, Outr Partner Terrorism Mitigation Action Items Short-Term #1 Enhance emergency planning, emergency response training and equipment to address potential terrorism incidents. local fire and law enforcement agencies, facility managers Ongoing X X X X X Long-Term #1 Upgrade physical security detection and response capability for critical facilities, including water systems and for any high-profile facilities such as major timber industry facilities and sites with large quantities of hazardous materials facility managers 5 Years X X X X X 4-16 5.0 Plan Adoption, Maintenance, and Implementation 5.1 Overview For a plan to be effective, it has to be implemented and maintained. Only through developing a system or routine will work items in this document be accomplished. The following sections depict how Benton County will manage the Pre-Disaster Mitigation Plan (PDM). The plan?s format allows it to review and update sections as new data becomes available. This keeps the plan current and relevant to Benton County. The benefits of keeping the plan active up-to-date include: ? Reducing the threat to life safety; protecting critical facilities; enhancing emergency and essential services; reducing the threat to property; creating a disaster resistant and resilient economy; and increasing public awareness, education, outreach, and partnerships ? Educating the public about natural hazard mitigation and specific mitigation efforts that the County is undertaking. ? Building mitigation partnerships throughout the community. ? The ability to apply for grants and other funding as opportunities become available 5.2 Plan Adoption The Benton County Pre-Disaster Mitigation Plan was adopted by the Benton County Board of Commissioners on 1/03/2006, making it the effective date of the plan. The Final Draft of the plan was submitted to OEM and FEMA for review approval, with the stipulation that edits required for approval were included in the adoption motion. FEMA approval of the Plan was received on TBD. FEMA approval means that Benton County?s Pre-Disaster Mitigation Plan meets national standards and that the County will continue to be eligible for hazard mitigation funding from FEMA?s Hazard Mitigation Grant Program, the Pre-Disaster Mitigation Program, and other programs. Benton County has the necessary human resources to ensure the Plan continues to be an actively used planning document. County staff has been active in the preparation of the plan, and have gained an understating of the process and the desire to integrate the plan into the Comprehensive Land Use Plan. Through this linkage, the plan will be kept active and be a working documents. Since 1996 and the creation of the initial Benton County Mitigation Master Plan, Benton County has experienced several disasters, including two Presidential and one Small Business 5-1 Administration declarations. These events have kept the interest of hazard mitigation planning and implementation alive at the Commissioner level. 5.3 Implementation The Benton County Pre-Disaster Mitigation Plan was developed and will be implemented through a collaborative process. The active collaboration in mitigation and emergency planning that exists within Benton County will insure the successful implementation of the plan. It will be guided by the Pre-Disaster Mitigation Plan Steering Committee while the Emergency Management Program will be Benton County?s coordinating agency and day to day plan activities. This consistent staffing allows for well-organized meetings and will ensure the right people are involved at the meetings, while the multi-partner Committee ensures participation and commitment from key community partners. Implementation of the mitigation actions identified in the Plan will engage the community. The participation that led to the Plan was the result of existing community networks and these networks will continue to participate as the community wide mitigation activities identified in the plan are begun. Some projects can be performed at the volunteer level, and others will require technical expertise. The stakeholders in the planning process will become project partners as needed on specific items. There are many organizations within the County that already cooperate due to common interests and concerns, including hazard mitigation. Organizations such as the City of Corvallis, Oregon Department of Forestry, Good Samaritan Regional Medical Center, Oregon State University, and large business will be important partners in the implementation of the Plan. To successfully complete action items will require project planning with active participation. Benton County has a proven history of involving and continues to involve multiple partners in planning and mitigation work. These partnerships with local, state, and federal partners has resulted in comprehensive plans and projects that could not have been completed by any agency alone. This cooperation is demonstrated by the Steering Committee makeup of all cities and large districts within Benton County. Additionally, the County and other partners have many existing programs that will be linked to mitigation projects. In 2004, the Benton County Planning Commission and Community Development Department conducted planning and public hearings for the rewriting of several chapters of the County Comprehensive Land Use Plan. The Benton County Emergency Manager was a member of the Steering Committee and participated in the development/exchange of ideas on Chapter 7 - Natural Hazards, and Chapter 6 ? Air, Land, Water Quality. The Director of Community Development is also a part of the Pre-Disaster Mitigation Plan Steering Committee. These links to each other?s committees have promoted sharing of information and 5-2 integration of goals/objectives that insure a systemic approach to reducing the risk to populations within Benton County. Additionally, the Benton County Emergency Management Council brings community partners and citizens together to share emergency management ideas and plans. This council, begun in 1990, has over 75 community participants and is more than a forum for sharing ideas. The council consists of several active sub-committees that conduct joint planning, public education, training, and mitigation activities throughout the region. The state, county, city, business, and citizen partnerships have resulted in projects that have spanned jurisdictional lines. The Council also received and administered the community FEMA Project Impact Grant in 1998 and parlayed the $300,000 seed money into over $7 million dollars of community activities, of which $6 million were mitigation projects. Even though Project Impact has been completed, the Council is still active with participation in the concepts and ideals of Project Impact. Continual meetings, collaboration, and partnership building is still the mainstay of the Council. These connections will continue for other plans and projects within the County. As development plans come into the Community Development Department, reviewers will need to keep in mind potential hazard mitigation actions that may need to be implemented. The adopted building codes for the County include many standards that mitigate potential hazard damage. The County stays current in adoption of upgraded codes, ensuring that the new construction activities will meet the highest standard available for hazards such as floods and seismic. The plan identifies many work items, with various estimated timelines for completion. Upon acceptance of the plan, the Steering Committee will meet and prioritize the list of work efforts. Some items will be emphasized based on grant funding periods, others on work plans. As items are completed, the Steering Committee will review and update the priority of work efforts. Benefit-Cost Analysis (BCA) will mostly be used to determine prioritization of ?brick and mortar? projects versus prioritizing all projects. Some project tasks can be incorporated into staff work plans as part of ?normal? business, while others tasks will require a CBA to determine when they are addressed. 5.4 Project Prioritization Project prioritization requires flexibility, due to the different sources of projects and funding. Projects can be identified through the citizen forums (Benton County Emergency Management Council), government agencies (Benton County Development Department or Public Works, City of Corvallis, City of Philomath, Oregon State University), or new community risk assessments. Each project is identified to address a need. The challenge is to decide which project, and application of monetary/equipment resources, will best meet the goals of the PDM. The benefit-cost analysis is an essential component of this decision/prioritization process. 5-3 The Steering Committee will consider all proposed projects and select projects that align with the plan?s goals. Again, a benefit-cost analysis (as described in step 3 below) will be part of the prioritization selection process. Such projects may then be incorporated into the plan as formal action items. Funding can then be considered for projects that have been formally incorporated into the plan. Depending on the potential project?s intent and implementation methods, several funding sources may be appropriate. Examples of mitigation funding sources include but are not limited to: FEMA?s Pre-Disaster Mitigation competitive grant program (PDM), Flood Mitigation Assistance (FMA) program, National Fire Plan (NFP), Title II and Title III funds, Community Development Block Grants (CDBG), local general funds, and private foundations, among others. The prioritization process utilizes a four-step process to prioritize activities to help ensure that mitigation dollars are used in a cost effective manner. Figure 5.1 illustrates the project prioritization process. Figure 5.1: Project Prioritization Process Overview PROJECT FUNDING & IMPLEMENTATION Step 1: Examine funding requirements Step 3: Complete quantitative, qualitative, and benefit-cost analysis Multi-Hazard PDM HMGP CDBG Local general funds Private foundations Flood Flood Mitigation Assistance Wildfire NFP SB360 Title II & III Projects Identified by the Committee Projects Identified Locally ? Residents, Organizations, County Staff Step 4: Steering Committee recommendation Project FundingProject Prioritization ProcessProject Sources Projects Identified through the Risk Assessment Step 2: Complete risk assessment evaluation Steering Committee incorporates selected projects into the NHMP as action items Source: Community Service Center?s Oregon Natural Hazards Workgroup at the University of Oregon, 2005 5-4 The Steering Committee and the Benton County Board of Commissioners have the option to implement any of the action items at any time, regardless of the prioritized order. This allows the committee to consider mitigation strategies as new opportunities arise, such as funding for action items that may not be of highest priority. As depicted in Figure 5.1, project sources and project funding can be received from many sources. The Steering Committee will then use the following four steps to prioritize projects. Step 1: Examine Funding Requirements The Steering Committee will examine the selected funding stream?s requirements to ensure that the mitigation activity would be eligible through the funding source. The Steering Committee may consult with the funding entity, Oregon Emergency Management, or other appropriate state or regional organization about the project?s eligibility. Step 2: Complete Risk Assessment Evaluation The second step in prioritizing the plan?s action items is to examine which hazards they are associated with and where these hazards rank in terms of community risk. The Steering Committee will determine whether or not the plan?s Risk Assessment supports the implementation of the action item i.e., mitigation activity. This determination will be based on the location of the potential activity and the proximity to known hazard areas, historic hazard occurrence, and the probability of future occurrence. Step 3: Complete Quantitative, Qualitative Assessment, and Economic Analysis Depending on the type of project and the funding source, either a quantitative or qualitative assessment of cost effectiveness will be completed to assist in prioritizing potential actions. In examining the feasibility of the plan?s prioritized action items, benefit-cost analysis would be encouraged for all structural mitigation projects. For FEMA- funded, nonstructural projects or projects funded through entities other than FEMA, a qualitative assessment will be completed to determine the project?s cost effectiveness. See Appendix C for more information on the process required for Step 3. Step 4: Steering Committee Recommendation Based on the steps above, the Steering Committee will recommend whether or not the mitigation activity should move forward. If the Steering Committee decides to sanction the action, a coordinating organization will be determined for the management of the project. 5-5 5.5 Plan Maintenance The Benton County Pre-Disaster Mitigation Plan will be monitored and evaluated on a regular basis as the community implements the action items within the Plan. The hazards that exist in the community will continue to exist, but the conditions within the community will continue to change. As these changes occur, the Plan needs to be reevaluated. This may be a change in the population or in the development patterns that were in place when the Plan was developed. Another change that may affect the effectiveness of the Plan would by changes in the values of the citizens of the County. Community values have be regularly monitored through Comprehensive Plan update process. As the Comprehensive Plan is implemented, the Pre-Disaster Mitigation Plan will need to be reviewed as well. Beyond the Comprehensive Plan, Benton County citizens will be informed of implementation efforts through the local newspaper coverage and ongoing Council meetings. The Steering Committee includes key decision makers and representatives from many jurisdictions. These representatives are tasked with identifying and incorporating mitigation planning into current and future projects. Additionally, the Pre-Disaster Mitigation Plan will be part of the County Comprehensive Plan and overlap of committee members insures that the values and objectives of the PDM are integrated into the community planning process. Local, state and federal agencies will conduct or refine studies that may lead to new or better information on specific hazards. The new information will need to be incorporated into other documents, such as the Comprehensive Plan and the Pre- Disaster Mitigation Plan. For example, this could include updated flood plains, identification of landslide areas or areas subject to seismic vulnerability. On an annual basis the Pre-Disaster Mitigation Plan Steering Committee will meet to review the Plan. This will be the opportunity to incorporate new information into the Plan and remove outdated items and completed actions. This will also be the time to recognize the success of the community in implementation of action items. All revisions of the Plan will be taken to the Board of Commissioners for acknowledgement as part of the Plan maintenance and implementation program. Initially, meetings will be held quarterly to begin the institutionalization process of mitigation planning. As efforts become incorporated into work plans, the steering committee could decide to conduct semi-annually meetings. If Quarterly meetings are discontinued, the Quarterly work processes listed in Figure 5.2 will be added to the semi-annual work process list. 5-6 Figure 5.2 Timetable of Steering Committee work process Quarterly ? Review activities and assignments ? Review old and new project proposals ? Review funding sources Semi Annually ? Review and prioritize project list ? Review or identify new issues/needs Annually ? Update risk assessment, based on new data ? Review process efficacy ? Review public involvement efforts ? Document successes and lessons learned ? Update Benton County Emergency Management Council 5 year ? Review update questions ? Review and update plan Quarterly and/or Semi-Annual Meeting The Steering Committee will meet to: ? Review assignments from previous meetings and monitor progress towards completion ? Initially review project proposals for completeness and applicability towards goals and objectives ? Review existing action items to determine appropriateness for funding ? Identify issues that may not have been identified when the plan was developed ? Prioritize potential mitigation projects using the methodology described in Figure 5.1 The convener will be responsible for documenting the outcome of the meetings. Annual Review Meeting The Steering Committee will meet annually to review updates of the Risk Assessment data and findings, discuss methods of continued public involvement, and document successes and lessons learned based on actions that were accomplished during the past year. As part of the community collaboration process, an informational report will be made to the Benton County Emergency Management Council. This is so members will know what activities are taking place and help determine if there is an opportunity for additional project partnerships. The convener will be responsible for documenting the outcomes of the meeting. 5-7 Five-Year Review of Plan This plan will be updated every five years in accordance with the update schedule outlined in the Disaster Mitigation Act of 2000. During the five-year plan update, the following questions should be asked to determine what actions are necessary to update the plan. The convener will be responsible for convening the Steering Committee to address the questions outlined below. ? Are the plan goals still applicable? ? Do the plan?s priorities align with state priorities? ? Are there new partners that should be brought to the table? ? Are there new local, regional, state, or federal policies influencing natural hazards that should be addressed? ? Has the community successfully implemented any mitigation activities since the plan was last updated? ? Have new issues or problems related to hazards been identified in the community? ? Do existing actions need to be reprioritized for implementation? ? Are the actions still appropriate given current resources? ? Have there been any changes in development patterns that could influence the effects of hazards? ? Have there been any significant changes in the community?s demographics that could influence the effects of hazards? ? Are there new studies or data available that would enhance the risk assessment? ? Has the community been affected by any disasters? Did the plan accurately address the impacts of this event? These questions will help the Steering Committee determine what components of the mitigation plan need updating. Emergency Management staff will be responsible for updating any deficiencies found in the plan based on the questions above. The revised/reviewed plan will be submitted for approval to the Benton County Board of Commissioners for another 5-year cycle. 5-8 6-1 6.0 FLOOD HAZARDS Benton County is subject to flooding from several different types of flood sources, including: 1) over bank flooding from the Willamette River and smaller rivers including Marys River and the Alsea River, 2) over bank flooding from numerous smaller creeks which are tributaries to the above rivers, and 3) local storm water drainage flooding. Flooding on streams and rivers within Benton County generally results from large winter storms from the Pacific, which often result in simultaneous flooding on many rivers and streams in an affected area. However, because of geographic variations in rainfall amounts and differences in drainage areas, slopes, and other watershed characteristics, the severity of flooding in any given rainfall event often varies significantly from stream to stream and location to location. Historically, most major floods in Benton County have occurred in the months of December, January and February, although flooding in other months is certainly possible. 6.1 Historical Floods in Benton County Historically, flooding has occurred in Benton County throughout the recorded history of the area, ever since the first European settlers arrived in the area in the mid-1800s. The FEMA Flood Insurance Studies for Benton County (August 5, 1986) and for Albany (July 7, 1999) have a brief history of major historical floods in Benton County. Major floods on the Willamette River occurred in 1861, 1890, 1901, 1909, 1923, 1964, 1972, and 1974. Lesser floods occurred in 1943, 1945, 1946, 1948, 1953, 1961, and 1977. The 1861 was the greatest flood event along the Willamette. Without flood control measures, the 1964 flood would have been the greatest flood of the 20th century; however, flood control measures greatly reduced the peak flood discharge and flood elevations and thereby greatly reduced areas affected by the flood. Even so, extensive flooding occurred in North Albany, South Corvallis and other areas along the river. Flooding potential along the Willamette River has been substantially reduced by the 11 major flood control reservoirs on the Willamette with about 1.7 million acre feet of flood control storage. Despite the reduction in flood potential from construction of the dams, portions of Benton County continue to have a significant level of flood risk from the major rivers as well as from the numerous smaller rivers and creaks running through 6-2 Benton County. The dams on the Willamette have not reduced flood risk on these smaller streams. 6.2 The 1996 Flood The most recent significant flood event in Benton County occurred in February 1996. Unusually heavy rains over the four-day period from February 5th to February 8th 1996 resulted in significant flooding on numerous rivers and streams throughout western Oregon. In Benton County, flood impacts continued for several days after the end of heavy rainfall. The following narratives about the 1996 flood are from: The Cascades West Region of Oregon and the February Flood of 1996: A Regional Flood Recovery Plan for Benton, Lane, Lincoln, and Linn Counties (November 1996). Benton County The already saturated ground caused the rain to flow into the creeks and soon overflow their banks in the north and south ends of Corvallis. 147 people were rescued by rubber raft in north Corvallis on Tuesday Feb 6. In the Philomath area, creeks reached flood stage early Tuesday morning and threatened homes. The situation continued to worsen throughout the county, but specifically in the City of Corvallis. The Marys River (Philomath/Corvallis) and Long Tom River (Monroe/Alpine) overtopped their banks and isolated homes and motorists, prompting more rescues throughout Tuesday and Wednesday. The Alsea River also flooded (southwest Benton County) and began to isolate homes. The Willamette River (Corvallis) came within 6 inches of flood stage, but did not flood. However, it affected the Marys and Long Tom, which could not feed into the Willamette and discharge their floodwaters. In total 2 people died and damages were estimated over $8 million dollars. The flood damages do not include the repair of a previously closed bridge of $550,000 and the $500,000 to flood proof the County Emergency Operation Center, located in the basement of the County Law Enforcement Building. City of Corvallis Shelters were established in Corvallis. Dixon, Oak and Squaw Creeks overflowed their banks, and storm runoff flooded many streets. The Marys River and Mill Race also overflowed their banks and affected south Corvallis. The sewer and storm drains were over capacity and sewage 6-3 contaminated much of the water. The main north street through town was closed at 8 pm, after many vehicles were stalled in the high water. Drainage ditches overflowed onto the highway and flooded homes and businesses in south Corvallis. Sandbagging attempts kept some of the water at bay, but not all of it. On Thursday morning, south Corvallis was cut off from the rest of the city. As the day worsened, the bridges over the Willamette (Hwy 34/20) were closed. The waters continued to back up into basements and began to flood key facilities (Pacific Power control station and Benton County Law Enforcement Building). On Friday, the waters crested and shuttles were used to bring residents to and from south Corvallis. Cost estimates of the flood for the City of Corvallis total $465,091. City of Philomath Flooding from the Marys River and smaller creeks damaged homes and facilities within the community. Affected were roads to the water and wastewater treatment plants, Marys River Park and the water draft site of Wren. Total damages reported were less than $10,000. For the 1996 flood in Benton County, FEMA-funded repair and response costs for eligible public entities totaled nearly $600,000. These costs were for Benton County, City of Corvallis, Corvallis School District and seven other FEMA-eligible applicants. The 1996 flood was significant for Benton County, but certainly not the maximum possible flood event. Much larger floods are possible. 6.3 Flood Hazards and Flood Risk: Within Mapped Floodplains 6.3.1 Overview FEMA Floodplain Maps show areas where the Federal Emergency Management Agency (FEMA) has determined that a flood hazard exists. Nearly all communities in Benton County have at least some portion of the mapped hazard areas, or floodplains, within their jurisdiction. The FEMA-mapped floodplains in Benton County are summarized below in Table 6.1 from the four FEMA Flood Insurance Studies (FIS) for Benton County. Each FIS includes a summary of historical flood experience along with quantitative data on stream discharges (volume of water flowing in the river or stream) and flood elevations. For the most part, the FEMA-mapped floodplains in Benton County include only areas along the larger rivers and streams, which also have significant concentrations of development and population. Throughout Benton County, there are many other localized areas that have significant flood risk but are not included in the FEMA mapped floodplains because the streams are too small and/or because the flood-prone population is too small. Furthermore, there are additional localities within Benton 6-4 County were flooding occurs because of local storm water drainage, rather than overbank flooding from rivers and streams. Such, local storm water drainage areas are not mapped by FEMA. Thus, evaluation of flood hazards in Benton County must consider not only the FEMA-mapped floodplains, but also the other localized areas of repetitive flooding or high flood risk outside of the mapped floodplains (see Section 6.4). Table 6.1 FEMA-Mapped Floodplains in Benton County Flood Insurance Study Flood Sources with Detailed Studies1 Flood Sources with Approximate Studies1 Willamette River Sequoia Ditch Marys River North Fork Squaw Creek Millrace and Millrace Overflow South Fork Squaw Creek Steward Slough Oak Creek Dixon Creek North Fork Dixon Creek South Fork Dixon Creek South Fork Dixon Creek Squaw Creek Unnamed tributary to Dixon Creek South Fork Squaw Creek Oak Creek Marys River East Fork Newton Creek Willamette River Benton County, Unincorporated Areas (August 5, 1986) Willamette River Greasy Creek Marys River North Fork Squaw Creek North Fork Alsea River South Fork Squaw Creek Newton Creek East Newton Creek Oak Creek Newton Creek Soap Creek Marys River Frazier Creek Alsea River Jackson Creek Millrace and Millrace Overflow Corvallis (July 2, 1984) Philomath (December 1, 1981) Albany ( July 7, 1999) 1 Detailed and approximate studies include specific portions of the reaches along these flood sources as listed in each Flood Insurance Study. FEMA Flood Insurance Rate Maps (FIRMs) for the above mapped areas show flood plain details such as the 100-year and 500-year flood plain boundaries. For Benton County, there are 17 FIRMs for cities and communities in unincorporated portions of the county. FEMA-mapped floodplains in Benton County include: 1) a broad swath of the lowlands along the reach of the Willamette River, 2) bands along the smaller FEMA-mapped rivers and creeks in Benton County, 6-5 3) portions of the larger cities and developed areas, including Corvallis, North Albany, Philomath, and Monroe. Of the larger population centers in Benton County, North Albany has the highest proportion of flood prone area and structures. However, Corvallis and Philomath also have significant developed areas within mapped flood plains. A synopsis of these FEMA mapped flood-prone areas in Benton County is given below in Table 6.2. Table 6.2 Synopsis of FEMA-Mapped Flood-Prone Areas in Benton County FIRM Maps Flood Source Geographic Area Willamette River band along the west bank of the river, extending to or near 1st Street, with wider flood-prone areas in the vicinity of Marys River and the Millrace and in the vicinity of Dixon Creek Dixon Creek, including North and South Forks Narrow bands along these creeks, extending to a wider band downtown in vicinity of Polk and Buchanan to the Willamette River Sequoia Ditch Area in vicinity of Sycamore Ave., Sequoia Ave. and 9th St. and area along Circle Blvd, east of the railroad tracks Steward Slew area in northeast Corvallis west of Canterbury, south to Plymouth Circle and Sherwood Way and west to the railroad tracks Oak Creek Area north of Highway 20/34 west of 27th Street Marys River Areas north and south of Highway 20/34 Squaw Creek, including North and South Forks narrow bands along these creeks, extending to the Marys River Mill Race and Marys River Area between Marys River and Millrace, east of the railroad tracks, south to vicinity of Tunison Ave. Willamette River large portions of North Albany Long Tom River and Shafer Creek mostly narrow band along these flood sources, affecting only small portions of a few streets or roads, but also affecting the wastewater treatment plant Marys River substantial area in southwest corner of Philomath, south of Main St., between 6th St. and 17th St. Newton Creek, including East Fork narrow bands along these creeks Willamette River band along the west bank of the river, for the entire reach of the river through Benton County, including a mix of developed, rural, and wildland areas Marys River banks along much of the river, including a mix of developed, rural, and wildland areas Alsea River, including North and South Forks narrow bands along these rivers, affecting some small developed areas Soap, Greasy, Frazier, Oak, Muddy and Bummer Creeks narrow bands along these creeks, affecting some small developed areas Benton County Unincorporated Areas (6 FIRMs) Corvallis (6 FIRMs) Albany (7 FIRMs, 3 of which include Benton County (North Albany)) Monroe (1 FIRM) Philomath (1 FIRM) 6-6 An important caveat in interpreting the FEMA floodplain maps (and the synopsis above) is that there are additional areas of Benton County, not within the mapped floodplains, that are also at flood risk. These flood-prone areas are discussed later in this chapter (Section 6.4). Full details of the FEMA-mapped flood plains in Benton County are shown on the 17 FIRMs referenced above. The following maps give an overview of these mapped flood- prone areas. The first map below provides an overview of mapped flood plains throughout Benton County. The following maps show more detailed data for areas with significant development within the mapped floodplains, including North Albany, North Corvallis, Corvallis (Dixon Creek Floodplain), Corvallis (Marys River Floodplain), and Philomath. Portions of the following smaller communities are also within FEMA- mapped floodplains: Alsea, Monroe, Blodgett, Summit, and Wren. For further details see the FEMA FIRM maps for these communities. 6-7 6-8 6-9 6-10 6-11 6-12 6.3.2 Flood Hazard Data For mapped floodplain areas, the flood hazard data included in the Flood Insurance Study (FIS) allow quantitative calculation of the frequency and severity of flooding for any property within the floodplain. Such calculations are very important for mitigation planning, because they allow the level of flood risk for any structure to be evaluated quantitatively. The example below illustrates these concepts. For example, for the Willamette River in North Albany in the vicinity of North Albany Road (across from the confluence of the Calapooia River), the 1999 FEMA FIS for Albany includes the following data: Table 6.3 Flood Hazard Data North Albany Road Vicinity Flood Frequency Discharge Elevation (years) (cfs) (feet) 10 117,000 195.9 50 172,000 200.1 100 200,000 202.2 500 272,000 206.0 The stream discharge data shown above are from the table on page 11 of the FIS for Albany, for the Willamette River stream gage at river mile 119.33, just downstream from the confluence of the Calapooia River. Stream discharge means the volume of water flowing down the river and is typically measured in cubic feet of water per second (cfs). The flood elevation data are from the Flood Profile Graph 1P in the FIS. Flood elevation data vary with location along the reach of the river and thus separate flood elevation data points must be read from the graph at each location along the river. The flood elevation data above for the Willamette River are at the convergence with the Calapooia River. Quantitative flood hazard data, such as shown above, are very important for mitigation planning purposes because they allow quantitative determination of the frequency and severity (i.e., depth) of flooding for any building or other facility (e.g., road or water treatment plant) for which elevation data exist. For example, a building located in North Albany Road in this vicinity (cf. Table 6.3 above), with a first floor elevation of 196 feet is expected to flood about once very 10 years, on average. 50-year, 100-year, and 500- year flood events would result in about 4.1 feet, 6.2 feet and 11 feet of water above the first floor, respectively. Thus, such a structure would demonstrably be at significantly high flood risk. However, another structure in the same vicinity with a first floor elevation of 200 feet would still be at flood risk, albeit at a much lower level of risk, with flooding above the first floor about once every 50 years, on average. 6-13 Such quantitative flood hazard data also facilitate detailed economic analysis (e.g., benefit-cost analysis) of mitigation projects to reduce the level of flood risk for a particular building or other facility. 6.3.3 Interpreting Flood Hazard Data for Mapped Floodplains The level of flood hazard (frequency and severity of flooding) is not determined simply by whether the footprint of a given structure is or is not within the 100-year floodplain. A common error is to assume that structures within the 100-year floodplain are at risk of flooding while structures outside of the 100-year floodplain are not. Some importance guidance for interpreting flood hazard is given below. A. Being in the 100-year floodplain does not mean that floods happen once every 100 years. Rather, a 100-year flood simply means that the probability of a flood to the 100-year level or greater has a 1% chance of happening every year. B. Much flooding happens outside of the mapped 100-year floodplain. First, the 100-year flood is by no means the worst possible flood. For example, for flooding along the Willamette River in North Albany, the 500-year flood is nearly four feet higher than the 100-year flood (cf. data in Table 6.3 above). Thus, floods greater than the 100-year event will flood many areas outside of the mapped 100-year floodplain. Second, many flood prone areas flood because of local storm water drainage conditions. Such flood prone areas have nothing to do with the 100-year floodplain boundaries. C. The key determinant of flood hazard and flood risk for a structure or other facility is the relationship of the elevation of the structure or facility to the flood elevations for various flood events. Thus, homes with first floor elevations below or near the 10-year flood elevation have drastically higher levels of flood hazard and risk than other homes in the same neighborhood with first floor elevations near the 50- year or 100-year flood elevation. The FEMA FIRM maps use a variety of nomenclature to describe different types of flood-prone area and flood plain classifications have changed over time. For reference, definitions of some important flood plain terms commonly used on FIRMs are given below. The FEMA floodplain maps include the following types of flood-prone areas: 1. Zone AE, within the 100-year floodplain, with base flood elevation (100-year flood) and detailed flood hazard data. On older FIRMs, numbered A-Zones (A1 to A30) have similar flood information. 6-14 2. Zone A, within 100-year flood plain, but without base flood elevation or detailed flood hazard data. 3. Zone AH, flood depths of 1 to 3 feet (usually areas of ponding), base flood elevations determined. 4. Zone AO, flood depths of 1 to 3 feet (usually sheet flow on sloping terrain). 5. Zone A99, to be protected from 100-year flood by Federal flood protection system under construction, no base flood elevations determined. 6. Zone X (shaded), areas of 500-year flood, areas of 100-year flood with average depths less than 1 foot or with drainage areas less than 1 square mile, and areas protected by levees from 100-year flood. On older FIRMS, Zone B areas have similar meaning. 7. Zone X (unshaded), areas outside 500-year flood plain. 8. Zone D, areas in which flood hazards are undetermined. 6.3.4 Caveats for Benton County Flood Insurance Study The Flood Insurance Studies (FIS) for Benton County were published between 1981 and 1999: Philomath (1981), Corvallis (1984), Benton County Unincorporated Areas (1986), and Albany (1999). Flood hazard conditions often change with time as channels and watersheds evolve with increasing development and other changes. Over time, the accuracy of a FIS typically diminishes with time and any FIS should be redone periodically to ensure that data are accurate and up to date for flood zoning and mitigation planning purposes. In many cases, increasing development within watersheds (which increases runoff), and gradual accumulation of sediment and debris in channels results in higher flood levels with time. In other cases, however, improvements in storm water management or channel improvements may results in lower flood levels. Simply because an FIS is old, does not necessarily mean that a FIS is obsolete or inaccurate. However, the older a study is, the more likely it is that channel or watershed conditions have changed over time. Therefore, as time passes, care should be taken in interpreting and using data from the FIS, especially in reaches of rivers or streams where substantial channel changes are documented or flood control measures have been added. FEMA has recognized that may FIS?s are old and is in-process with a nationwide map modernization program which is intended to update all of the FIS?s and FIRMs and map additional areas. However, this map modernization program will not be completed for 6-15 several years at the earliest. Meanwhile, the existing FIS?s and FIRMs for Benton County are generally the best available flood data. 6.4 Flood Hazards and Flood Risk: Outside of Mapped Floodplains The discussion above in Section 6.3 above applies only to the limited portions of Benton County that are within the FEMA-mapped floodplains of the major rivers and portions of some of the smaller streams. For mitigation planning purposes, it is very important to recognize that flood risk for a community is not limited only to areas of mapped floodplains. Other portions of Benton County outside of the mapped floodplains may also at relatively high risk from over bank flooding from streams too small to be mapped by FEMA or from local storm water drainage. In Benton County as a whole there are dozens of small creeks with unmapped floodplains. Many areas of Benton County outside of mapped floodplains are also subject to repetitive, damaging floods from local storm water drainage, separate from overbank flooding from creeks too small to be mapped. In many cases, local storm water drainage flooding occurs along unnamed gullies or simply in low spots. There are probably numerous such flood prone sites in Benton County; many of these sites may have experienced repetitive flooding over many years. Unlike FEMA-mapped floodplains for larger rivers and creeks, areas subject to storm water drainage are not systematically mapped. Storm water drainage systems vary markedly within Benton County. In urban areas and some smaller communities, storm water drainage consists of drains and an underground pipe system. In lower population density areas, storm water drainage systems are generally open drainage ditches. In rural areas, storm water drainage systems are typically hit or miss, with culverts or other drainage infrastructure built only in limited locations with repetitive flooding episodes. A complete inventory of Benton County?s storm water drainage system is beyond the scope of this mitigation plan. Individual communities can provide information about their specific local drainage system. In general, however, storm water drainage systems, including those in Benton County, are almost always designed to handle only small to moderate size rainfall events. Storm water systems are sometimes designed to handle only 2-year or 5-year flood events, and are rarely designed to handle rainfall events greater than 10-year or 15-year events. For local rainfall events that exceed the collection and conveyance capacities of the storm water drainage system, some level of flooding inevitably occurs. In many cases, local storm water drainage systems are designed to allow minor street flooding to carry off storm waters that exceed the capacity of the storm water drainage system. In larger rainfall events, flooding may extend beyond streets to include yards. In major rainfall events, local storm water drainage flooding can also flood buildings. In extreme cases, local storm water drainage flooding can sometimes result in several feet of water in buildings, with correspondingly high damage levels. 6-16 6.5 Inventory Exposed to Flood Hazards in Benton County Critical facilities such as emergency communications, fire stations, police stations, medical care facilities are, by definition, particularly important to a community. Similarly, key transportation and utility infrastructure are also particularly important to a community. One important action item for Benton County Hazard Mitigation Plan is to compile an inventory of such critical facilities that are at high risk for each hazard, including floods. A preliminary list of critical facilities located within the FEMA-mapped 100-year or 500-year floodplains, or otherwise perceived to be at high flood risk is given below in Table 6.4. These facilities are also shown on the map following Table 6.4. Transportation routes subject to flooding are shown on the map following the critical facilities map. To quantify the level of flood hazard for buildings, other facilities or infrastructure, within mapped floodplains, it is necessary to determine the elevations of these structures. Only by determining the elevation of each potentially flood-prone structure, can the level of flood hazard (frequency and severity of flooding) be calculated accurately. Similarly, acquiring elevation data for additional structures within the 500-year flood plain as well as for structures in other flood-prone areas outside of mapped floodplains would greatly increase the accuracy of hazard, inventory, and vulnerability assessments for floods in Benton County. Compiling and interpreting such elevation data, especially for critical facilities is encouraged as a high priority action item. The best structure elevations (first floor elevations) are those determined accurately by surveying. Flood insurance certificates generally include survey elevation data. Absent survey data, however, useful estimates of elevations for structures can often be made by reference to elevations of nearby structures or public infrastructure with surveyed elevation data. In addition to elevation data, quantifying the level of risk faced by these structures requires basic data about each structure, including building data (square footage, number of stories, with or without basement), and information on the type and importance of function (residential, commercial, public). Additional sites of repetitive flood problems outside of the mapped floodplains are also included below in Table 6.4. As noted above, many localized areas of Benton County, outside of the mapped floodplains, are also subject to relatively high levels of flood risk. To quantify the level of flood risk posed by these areas, historical data should be systematically compiled to include documentation of the frequency and severity of flooding. Severity of flooding can include dollar estimates of past damages, if available, and/or simple narratives reporting whether the flooding in a given area is limited to minor street and yard flooding only, or whether flooding is severe enough to produce road damages, road closures, or damages to other infrastructure or buildings as well. 6-17 Table 6.4 Critical Facilities with 100-Year Floodplains ALBANY School ALBANY School Alsea Water Treatment Benton Public Works/Waste Water Treatment Corvallis Fire Department Drill Tower Corvallis Fire Station Corvallis Public Works Corvallis Parks Department Corvallis KLOO/KFAT Radio Transmitter Corvallis Long Distance Telephone Corvallis Water Treatment Monroe Sewage Treatment Facility Philomath Library Philomath City Hall Philomath Sewage Treatment Facility The above list of flood prone facilities is only a sample of flood prone facilities in Benton County and may not be complete. Other critical facilities and infrastructure is like to be at flood risk, within mapped floodplains and outside of mapped floodplains. A more complete inventory of such facilities is a high priority for mitigation planning and mitigation actions for Benton County. Critical facilities and major transportation routes at flood risk are shown on the following two maps. 6-18 6-19 6-20 6.6 Flood Loss Estimates and Flood Risk 6.6.1 Flood Loss Estimates For the FEMA-mapped floodplains, the digital FEMA FIRM maps (Q3) provide one basis to quantify the flood risk throughout Benton County, when combined with inventory data on buildings and infrastructure within the mapped floodplains. The following paragraphs present summary flood loss estimates from the modeling of flood risk in Benton County, from the Regional All Hazard Mitigation Master Plan for Benton, Benton, Lincoln, and Linn Counties (Phase One, 1998). See the Phase One Plan for further details of these calculations. The FEMA Q3 digital flood maps for Benton County show the geographic areas within mapped floodplains for 100-year and 500-year flood events. The geographic extent of these mapped flood plains is tabulated below in Table 6.5. Table 6.5 100-year and 500-year Floodplain Data for Benton County County Area (sq. km) Area in 100-year floodplain (sq. km) Percent in 100-year floodplain Area in 500- year floodplain (sq. km) Percent in 500-year floodplain Benton 1,754 92 5.25% 94 5.36% The data in Table 6.5 show that about 5.25% and 5.36% of the total geographic area of Benton County are located in the 100-year and 500-year floodplains, respectively. These data are for the entire county; separate data are not available for urban and rural areas. However, the percentages of land area within the mapped floodplains appear approximately similar for the larger cities and the smaller communities of Benton County. Although the data in Table 6.5 are informative, what is really desired for mitigation planning purposes is the percentage of the built environment (buildings plus infrastructure) that are subject to flood hazards. That is, what is the level of flood risk? To assess the level of flood risk, the inventory of buildings and infrastructure must be overlain onto the mapped flood plains. We conduct a preliminary flood risk assessment for Benton County, using census tract data and other nationally available data sources as outlined in the Phase One Plan. These default data sources generally contain data sorted by census tract and do not sort data as to whether or not the inventory is within the mapped floodplains. For this Level One Risk Assessment, we make the simple approximation that the fraction of 6-21 buildings in a given census tract that are located within the mapped floodplain is the same as the percentage of roads in the census tract that are located within the mapped floodplain. This approximation appears reasonable, since the location of buildings is well correlated with the location of roads, albeit certainly not exact. With these assumptions, the estimated numbers of buildings in each county located within the 100- year and 500-year floodplain are as shown in Table 6.6. The 500-year floodplain data are inclusive of the 100-year data; the difference between the 500-year and 100-year data indicates the estimated number of buildings (2,545) outside of the 100-year floodplain, but within the 500-year floodplain. Table 6.6 Estimated Number of Buildings in Mapped Floodplains (assuming same percentages as roads in each census tract) Buildings in 100-year Floodplain Buildings in 500-year Floodplain County Total Number of Buildings Percent Number Percent Number Benton 20,077 10.31% 2,070 13.10% 2,630 These rough estimates may somewhat overestimate the percentages of buildings located in the floodplains, for two reasons. First, there is probably some degree of risk aversion; that is, people are probably less likely to build buildings in the floodplains, than not, at least in recent decades. Second, many structures may have first floors elevated somewhat above grade level. Thus, although a structure?s footprint maps into the 100- year or 500-year floodplain, a 100-year or 500-year flood may not actually flood the structure itself. These caveats notwithstanding, the above estimates of the approximate numbers and percentages of buildings located within the mapped floodplains are at least a useful starting point for planning purposes. Overlays of parcel data with floodplain boundaries in Benton County yield results similar to those shown above as shown in Table 6.7. Table 6.7 Parcels and Dwellings in Floodplains Category Benton County 100-Year Floodplain 500-Year Floodplain1 Parcels 32,538 5,708 1,851 Market Value $5,799,334,117 $1,178,989,191 $470,917,775 Dwellings 9,787 1,860 291 1 within 500-year floodplain, but above 100-year floodplain. 6-22 With the above approximations, using Census data on the number, size, and function of buildings (residential, commercial, industrial, agriculture, public) and using default data on the breakdown of types of buildings, we then use FEMA depth-damage tabulations flood damages to estimate the vulnerability of the inventory as a function of flood depth. To model flood risk accurately, it is necessary to have elevation data on structures. In the absence of such data on a regional basis, we made additional approximations as discussed in the Phase One Plan. With the above assumptions, we estimate the total flood losses to buildings and contents in 100-year and 500-year flood events. We recognize that it is highly unlikely that all flood-prone areas in an entire county will experience 100-year or 500-year events at the same time. Nevertheless, such estimates are useful as an upper bound on potential flood losses to buildings in major floods. These estimates are shown in Table 6.8 Table 6.8 Estimated Building Damages in Mapped Floodplains County 100-year Flood 500-year Flood Benton $104,600,00 $139,500,000 The building damages shown above are based on a replacement value of $100/sf, which roughly considers both buildings and typical contents. As discussed above, these estimates probably overestimate flood losses. However, in addition to building damages within mapped floodplains, there will also be building damages outside of mapped floodplains. Furthermore, there will also be damages to infrastructure, not included in the tabulations above. The loss estimates shown above are very approximate and should not be interpreted literally, but rather as indications that flood damages in major floods in Benton County could reach into the tens of millions of dollars. Concurrent flooding of the Willamette River along with other rivers and streams could result in damages in the 100 million dollar range. As noted earlier, the construction of major dams on most of the major rivers in Benton County has substantially reduced the level of flood risk for most communities in Benton County. Absent these dams, a recurrence of major floods experienced in the 19th century (e.g., 1861 or 1890) would likely result in damages in the many hundreds of millions of dollars with major portions of many cities and smaller communities under many feet of floodwaters. Finally, these estimates of potential flood damages are for the FEMA-mapped floodplains only. Although the FEMA-mapped floodplains include much of the flood- prone inventory of buildings and infrastructure in Benton County, there are additional flood-prone areas outside of the mapped floodplains. 6-23 Similar approximate flood damage and loss estimates can be made using loss estimation calculation tools such as FEMA?s HAZUS-MH loss estimation software. However, accurate flood loss estimates for specific communities requires much more detailed data as discussed below in the following section. 6.6.2 Techniques for More Accurate Flood Loss Estimates Obtaining more detailed inventory information, including elevations of flood prone structures, can make more accurate flood loss estimates for specific areas of Benton County. Then, the economic impacts of floods can be estimated more completely using the approaches outlined below. For most residential structures and many similar commercial and public structures, the likely amount of building damage from floods of any given depth can be estimated approximately using FEMA depth-damage tables. These depth damage tables are derived from Federal Insurance Administration flood insurance claims data for several million properties and thus represent typical damage levels for typical structures. Although actual damages will vary somewhat from structure to structure, depending also on flood conditions such as duration, velocity, and degree of contamination, these typical values represent a good starting point to estimate flood damages for typical structures and thus to help quantify the level of flood risk. In estimating flood losses or evaluating flood risk (for a structure or a whole community) it is very important to recognize that the economic impact of floods includes not only damages to buildings and contents but other economic impacts as well, including: 1. damages to yards, vehicles, and outbuildings (not in depth damage data above), 2. displacement costs for temporary quarters while repairs are made, 3. loss of business income, 4. loss of public services. In some cases, these economic impacts of floods can be a significant fraction of building and contents damages, or even larger, especially for critical facilities or critical infrastructure. FEMA?s publication What is a Benefit? Draft Guidance for Benefit-Cost Analysis provides an excellent primer, along with typical values and simple economic methods, to place monetary values on the loss of function of buildings, critical facilities, roads and bridges, and utility systems. 6-24 6.7 Flood Insurance Data for Benton County. The National Flood Insurance Program (NFIP) maintains a database of all flood insurance policies in the United States. NFIP data for Benton County are summarized below in Table 6.9. As shown below, there are 953 flood insurance policies in place in Benton County as a whole, with about 35% of these outside of the larger cities. The FEMA NFIP database indicates that 215 of these insured structures (23%) are post-FIRM structures and thus may have been built in accord with flood plain management regulations governing minimum first floor elevations vis-?-vis the base flood (100-year) elevation. However, 735 of these structures (77%) are pre-FIRM structures and likely to be lower, more flood-prone elevations. The data of construction and pre- or post-FIRM status of the remaining 3 structures is not known. Table 6.9 NFIP Data for Benton County (August 2004) Jurisdiction Policies Repetitive Loss4 Albany 1 202 0 Benton 2 341 0 Corvallis 370 0 Monroe 4 0 Philomath 36 0 Benton County3 953 0 1 Benton County portion (North Albany) 2 Benton County outside of listed cities 3 Benton County (entire) 4 A property is considered a repetitive loss property when there are 2 or more losses reported which were paid $1,000 or more on each loss. The 2 losses must be within 10 years of each other and be at least 10 days apart. Only losses from 1/1/1978 that are closed are considered. FEMA?s national repetitive loss list includes all insured properties that have experienced two or more insured losses of at least $1,000 for which the flood events were at least 10 days apart but not more than 10 years apart. The FEMA repetitive loss list provides one indication of properties that may be at high risk for future flooding. However, because these claims data do not consider the severity or frequency of the flood events causing the flood loss claims, the repetitive loss list is not mathematically rigorous. For 6-25 example, some properties on the list may have simply been unlucky and have experienced two flood events with low probabilities (e.g., 100-year or greater events) within a short time period. Thus, the properties on the repetitive loss list may be at relatively high flood risk or they may not. Correspondingly, there are almost certainly other properties within Benton County at equal or higher levels of flood risk that are not on the FEMA repetitive loss list. These properties may not have flood insurance or simply may have been lucky over the relatively short reporting period for the NFIP repetitive loss list (data since 1978). Despite these limitations of FEMA?s repetitive loss list, properties within Benton County on the repetitive loss list may be good targets of opportunity for flood mitigation. Most of FEMA?s mitigation programs list repetitive loss properties as high priorities for mitigation and thus obtaining FEMA funding for properties on the repetitive loss list may be more likely than for properties not on the list. For reference, we note that the very approximate calculations presented above in Table 6.6 estimated about 2,070 buildings with footprints within the 100-year floodplain. The actual number of flood insurance policies in Benton County, 953, (cf. Table 6.9 above) is about 50% of this estimate. A 50% ratio of flood insurance policies to structures in the 100-year flood plain is more of less typical of many communities. The lower number of policies most likely results from a combination of factors, including homeowners who simply choose not to buy flood insurance, buildings not required to have flood insurance or not having insurance whether required or not as well as buildings whose footprint is in the 100-year flood plain but whose first floor elevation is above the 100-year flood elevation. 6-26 6.8 Summary of Flood Risk for Benton County The flood hazard, vulnerability and risk data, estimates and analyses presented above are summarized in the following table. Table 6.10 Summary of Flood Risk for Benton County Question Commentary a. overbank flooding from Willamette and Mary's Rivers and numerous smaller streams Affects portions of every community in Benton County. b. storm water drainage flooding Affects portions of many communities and rural areas. a. FEMA-mapped floodplains Every major community in Benton County has portions of the community within FEMA-mapped floodplains. North Albany has the largest percentage of flood-prone structures, but significant areas of Corvallis and Philomath are also within mapped floodplains. b. areas outside of FEMA-mapped floodplains Numerous locations affected by storm water drainage and flooding on smaller, unmapped streams; complete inventory of flood prone sites not yet available a. Buildings Complete inventory not yet available. Rough estimate is that about 2,070 buildings may be within footprint of 100-year flood plain. b. Critical facilities Complete inventory not yet available. b. Roads and other infrastructure As demonstrated by the 1996 flood, every major highway in Benton County and many secondary roads are subject to closure during flood events. a. roads Road closures and road damages happen to some extent almost every year b. buildings Relatively few buildings appear to be at extremely high flood risk (10-year floodplain or lower), but many buildings are at risk from flooding in larger less frequent flood events a. frequent flooding (annual or every few years) Very frequent flooding appears to impact primarily roads and relatively few buildings and other facilities b major floods (25-year, 50-year, 100-year etc. events) Increasingly major floods affect increasingly large fractions of the population, building stock and infrastructure of Benton County. A widespread 100-year flood event could result in up to one hundred million dollars of damages and directly affect over 2000 buildings and several thousand people. How serious is the flooding problem? What is the source and type of the flood problem? What is the geographic area affected by the flooding? What inventory of buildings and infrastructure are at risk? How frequent is the flooding problem? 6-27 6.9 Common Flood Mitigation Projects Potential mitigation projects to reduce the potential for future flood losses cover a wide range of possibilities. For either major rivers or the creeks, it would be theoretically possible to reduce future flood losses by building levees or floodwalls. In practice, however, such projects are often very expensive and have a host of environmental and other regulatory hurdles. For the smaller creeks, channel improvements to improve water conveyance capacity and removal of flow-restriction obstructions may be desirable. Another possibility for some of the smaller creeks would be to construct detention ponds upstream to temporarily store water during high rainfall periods. Detention ponds are basically leaky dams, designed to be dry during normal conditions. Detention ponds typically have restricted outlets with controlled flow rates. Thus, during periods of high inflow into the pond, water is stored temporarily and then gradually released. The effect of detention ponds is to lower peak discharge values and thus to lower peak flood elevations. For areas of Benton County subject to flooding from storm water drainage, various storm water drainage system improvements may be desirable. Typical improvements include upgrades to the size of drainage ditches or storm water drainage pipes and upgrades to pumping capacity (for pumped portions of drainage systems). Another possibility for some areas may be construction of local detention ponds. For critical facilities at low elevations with high flood risk, such as the water and wastewater treatment plants, construction of berms or floodwalls to protect the facilities may be desirable. For residential, commercial or public facilities at high flood risk, elevation of structures or, for structures at very high flood risk, acquisition and demolition are potential mitigation options. Elevation and acquisition (especially) are expensive mitigation options that are generally not cost-effective unless the levels of flood hazard and flood risk are rather high. That is, these mitigation options are most attractive for structures deep in the flood plain (i.e., with first floors below the 10-, or 20-, or 30-year flood elevations). For structures outside of mapped floodplains, elevation or acquisition would likely be cost-effective only for structures with a strong history of major, repetitive flood losses. For structures near the fringe of the 100-year flood plain, near the 100-year flood level, or with some history of repetitive flood losses, various small-scale flood loss reduction measures such as elevation of furnaces and utilities may be desirable. The following table contains flood mitigation action items from the Master Action Item table in Chapter 4. 6-28 . 6-29 Table 6.11 Flood Mitigation Action Items Mitigation Plan Goals Addressed Hazard Action Item Coordinating Organizations Timeline Life Safe Critical Facilities and Eme Services Protect Property Disaster Resilient Econo Public Education, Outr Partner Flood Mitigation Action Items: Within FEMA-Mapped Floodplains Short-Term #1 Complete inventory of critical facilities within 100-year and 500- year floodplains, with GIS mapping if possible Benton County GIS, cities, special districts Ongoing X X X X Short-Term #2 Complete inventory of residential and commercial buildings within 100-year and 500-year floodplains, with GIS mapping if possible Benton County GIS, cities, special districts Ongoing X X X Short-Term #3 Consult with property owners and explore mitigation actions for any Benton County properties on FEMA's national repetitive loss list Benton County Hazard Mitigation Steering Committee / Community Development / BC Em Mgt 1 year X X X X Long-Term #1 Survey elevation data for critical facilities, residential buildings and commercial buildings within the 100-year floodplain and establish flood mitigation priorities Local emergency service agencies, Benton County Hazard Mitigation Steering Committee 2-5 years X X X X X Long-Term #2 For critical facilities within the 100-year floodplain and for other structures deep within the 100-year floodplain explore mitigation options with property owners and implement mitigation measures Local emergency service agencies, Benton County Hazard Mitigation Steering Committee 2-10 years X X X X X Flood Mitigation Action Items: Outside of FEMA-Mapped Floodplains Short-Term #1 Complete the inventory of locations in Benton County subject to frequent storm water flooding Benton County Roads and GIS, cities, special districts Ongoing X X X X X Long-Term #1 For locations with repetitive flooding and significant damages or road closures, determine and implement mitigation measures such as upsizing culverts or storm water drainage ditches Benton County Engineer, Community Development, cities, special districts Ongoing X X X X X 6-30 This Page Left Blank 7.0 WINTER STORMS 7.1 Overview Winter storms affecting Benton County are generally characterized by a combination of heavy rains and high winds throughout the county, sometimes with snowfall, especially at higher elevations. Heavy rains can result in localized or widespread flooding, as well as debris slides and landslides. High winds commonly result in tree falls which primarily affect the electric power system, but which may also affect roads, buildings and vehicles. This chapter deals primarily with the rain, wind, snow and ice effects of winter storms. Larger scale flooding is addressed in Chapter 6. Debris flows and landslides are addressed in Chapter 8. For completeness, we also briefly address other weather events in this chapter, including severe thunderstorms, hail, lightning strikes and tornadoes. The frequency, severity, and impacts of such weather events are generally minor for Benton County, compared to winter storm effects (see Section 7.5). Winter storms can affect the area directly, with damage within Benton County, or indirectly, with damage outside the area but affecting transportation to/from the area and/or utility services (especially electric power). Historically, Benton County has often been subject to both direct and indirect impacts of winter storms. The winter storms that affect Benton County are typically not local events affecting only small geographic areas. Rather, the winter storms are typically large cyclonic low-pressure systems moving from the Pacific Ocean and that thus usually affect large areas of Oregon and/or the whole Pacific Northwest. Historical winter storm data complied by the Portland Office of the National Weather Service (www.wrh.noaa.gov/Portland/windstorm.html) list the following major winter storm events with substantial wind damage in Oregon: 1. February 7, 2002 2. December 12, 1995 3. November 13-15, 1981 4. March 25-26, 1971 5. October 2, 1967 6. March 27, 1963 7. October 12, 1962 8. November 3, 1958 9. December 21-23, 1955 10. December 4, 1951 11. November 10-11, 1951 12. April 21-22, 1931 13. January 20, 1921 14. January 9, 1880. 7-1 The website referenced above has informative narrative summaries of each winter storm event, including wind speed data and damage reports. Similar summaries of historical windstorm data have been compiled by Wolf Read at Oregon State University (http://oregonstate.edu/~readw/). This OSU website has a vast archive of historical winter storm data for Oregon. The specific severity and impacts of the major historical winter storm events listed above varied significantly with geographic location within Oregon. However, in terms of sustained wind speeds and damage levels, the 1880 and 1962 storms stand out as the most severe such events for Oregon. 7.2 Rain Hazard Data Severe winter storms in Benton County often include heavy rainfall. The potential impact of heavy rainfall depends on both the total inches of rain and the intensity of rainfall (inches per hour or inches per day). In the context of potential flooding, ?rainfall? also includes the rainfall equivalent from snowmelt. Flash floods, which are produced by episodes of intense heavy rains (usually 6 hours or less) or dam breaks are rare in Benton County (and western Oregon as a whole) but do represent a potential meteorological hazard. Large drainage basins, such as that for the Willamette River typically have response times of several days: the total rainfall amounts (plus snow melt) over periods of several days or more are what determines the peak level of flooding along large rivers. Smaller rivers may have response times of several hours up to a day or so. Smaller, local drainage basins have even shorter response times and levels of peak flooding may be governed by rainfall totals over a period of an hour to a few hours. However, for the Willamette River, there are numerous large multi-purpose dams and thus the usual natural correlation between rainfall events and flood levels does not completely apply. Rather, flooding along such rivers is heavily governed by water release patterns from the dams. For the major rivers, dam operating characteristics and capacities are included in the flood modeling for FEMA- mapped floodplains (see Chapter 6). Benton County annual rainfall data are summarized in Table 7.1 below two representative locations. The Corvallis and Alsea Fish Hatchery data are generally representative of eastern and western Benton County, respectively. 7-2 Table 7.1 Benton County Rainfall Data Location Average Annual Precipitation (inches) Lowest Annual Precipitation (inches) Highest Annual Precipitation (inches) Period of Record Corvallis 40.96 23.68 (1930) 73.21 (1996) 1889-2004 Alsea Fish Hatchery 91.83 62.69 (1985) 139.02 (1996) 1954-2004 www.wrcc.dri.edu Data for Corvallis (OSU) and Alsea Fish Hatchery weather stations from Average annual rainfall amounts are moderately high throughout Benton County, with higher averages in western portions of the county. The lowest average annual rainfalls of about 40? are in eastern Benton County. The highest average annual rainfall location in Benton County is in the lightly populated corner of the county near Hoskins, which has annual rainfall of more than 140?. As shown above, there are also substantial variations in annual rainfall from year to year. The rainfall data shown in Table 7.1 give general overview of the potential for winter storm flooding in Benton County, but whether or not flooding occurs at specific sites depends heavily on specific local rainfall and local drainage conditions. Statistical rainfall data for Benton County are shown on the following maps from NOAA data. These maps show the annual rainfall data and the 24-hour rainfall amounts for various return periods: 2-years, 25-years, and 100-years. The frequency of rainfall events is interpreted in the same manner as the frequency of flood events. Thus, a 2-year rainfall event simply means that such rainfalls have a 50% chance of happening in any given year. A 25-year or 100-year rainfall event mean simply that such rainfalls have a 4% or 1% chance, respectively, of happening in any given year. Such rainfall maps are prepared using what is known as orographic modeling. Rainfall gauge stations are relatively widely spaced. However, for modeling the localized impacts of heavy rainfall, higher resolution rainfall maps are needed. Orographic modeling considers topography, wind effects, and soil conditions and calibrates rainfall contours to conform to measured runoffs from stream gauge readings. Using these modeling techniques, rainfall maps are produced with higher spatial resolution than would be possible relying solely on rain gauge data. Evaluating the potential localized flood impacts of winter storms, these 24-hour precipitation maps provide useful information. The 24-hour precipitation totals are a reasonable measure of flood risk for small drainage basins. Longer duration precipitation totals govern flooding on larger rivers, but such flooding is already included in the modeling behind FEMA?s floodplain mapping and covered by the discussion of flood hazards in Chapter 6. 7-3 For Benton County as a whole, we note that 2-year rainfalls in 24-hours range from less than 3? to 6?. 25-year 24-hour precipitation totals range from less than 4? to above 9?. 100-year 24-hour precipitation totals range from less than 5? to above 10?. In each case, the lower rain totals are for areas in eastern Benton County and the higher totals are for mountainous areas in western Benton County. Such totals are high enough to generate significant potential localized flooding problems. However, whether or not localized flooding does occur depends on specific local drainage conditions. For example, 5" of rain in one area may cause no damage at all, while 5" of rain in a nearby area may cause road washouts and flooding of buildings. 7-4 Benton County Average Annual Rainfall Map 7-5 Benton County: 2-Year 24-Hour Rainfall 7-6 Benton County: 25-Year 24-Hour Rainfall 7-7 Benton County: 100-Year 24-Hour Rainfall 7-8 For Benton County, identification of specific sites subject to localized flooding during winter storms is based on historical occurrences of repetitive flooding events during past winter storm events. The flood-prone sites in Benton County identified in Chapter 6 Floods are for combination of overbank flooding from streams and rivers and from local storm water drainage flooding. See Table 6.4 and the maps of Flood Hazards to Critical Facilities and Transportation in Chapter 6. Additional sites in Benton County with a history of repetitive flood problems are shown below in Table 7.2; this list is representative but not complete, there are other repetitive loss sites as well. Table 7.2 Repetitive Flood Sites in Benton County Location Notes Law Enforcement Building, Corvallis Police Dept, regional communications, county mainframe computer Quarry Rd., North Albany 20-30 homes at risk Dixon Creek between Buchanan Ave. and Circle Blvd., Corvallis 30 homes threatened Avery Dr., south to the Mill Race, South Corvallis several homes and businesses threatened, lifeline blocked Kiger Island Rd., east of bridge over Booneville Channel 25-30 homes isolated 7.3 Wind Hazard Data Wind speeds associated with winter storms vary depending on meteorological conditions, but also vary spatially depending on local topography. For Benton County, the wind hazard levels are generally highest along the Willamette Valley and then fairly uniform across most of the rest of the county. In the mountainous areas, however, the level of wind hazard is strongly determined by local specific conditions of topography and vegetation cover. Thus, there are probably localized areas in western County with high wind hazard levels that are not shown on the overview maps discussed below. A regional overview of wind hazards is shown by the data in Figures 7.3 and 7.4, which show contours of wind speed (in kilometers per hour) for western Oregon (Wantz and Sinclair, Distribution of Extreme Wind Speeds in the Bonneville Power Administration Service Area, Journal of Applied Meteorology, Volume 20, 1400- 7-9 1411, 1981). These data are for the standard meteorological data height of 10 meters (about 39 feet) above ground level. Figures 7.3 and 7.4 show wind speed contours for recurrence intervals of 2-years and 50-years, respectively. These data are for sustained wind speeds. Peak gusts are commonly 30% or so higher than the sustained wind speeds. These wind-speed data are fairly old, but still representative of overall windstorm conditions in Oregon and in Benton County. 7-10 Figure 7.3 Wind Speed Contours for 2-Year Recurrence Interval (km/hour) 7-11 Figure 7.4 Wind Speed Contours for 50-Year Recurrence Interval (km/hr) 7-12 7-13 Return Period Sustained Wind Speeds (km/hr) Sustained Wind Speeds (miles/hr)1 2-year 60 to 70 37 to 43 50-year 100 to 115 62 to 71 1 Conversion from map contours in kilometers per hour is 0.6214 miles per kilometer Data from the above maps are summarized below in Table 7.5. Table 7.5 Wind Speed Data for Benton County For Benton County, the 2-year recurrence interval sustained wind speeds range from about 60 to 70 km/hour or about 37 to 43 miles per hour. These 2-year wind speeds are too low to cause widespread substantial wind damage. However, there may be significant local wind damage at sites where local wind speeds are higher or where there are especially exposed locations, such at the boundary between clear cut and forested areas. For Benton County, the 50-year recurrence interval wind speeds range from about 100 to 115 km/hour or about 62 to 71 miles per hour. These wind speeds are high enough to cause widespread wind damage. Damage may be severe at particularly exposed sites. Thus, for most regions of Benton County winter storms with significant direct wind damage are not likely every year or every few years, but perhaps once every decade or so, on average, with major windstorm events happening at intervals averaging a few decades. The maps shown above have limited spatial resolution for Benton County, but suggest that the potential for damaging winds may be somewhat higher in eastern Benton County along the Willamette River than elsewhere. Locations in Benton County with a history of wind damage (mostly tree falls affecting utilities and roads) are shown on the following map. Benton County Wind Hazard: Locations with a History of Wind Damage 7-14 7.4 Snow and Ice Hazard Data for Benton County Winter storms can also involve ice and snow, most commonly at the higher elevations in Benton County, but sometimes in the Willamette Valley as well. The most likely impact of snow and ice events on Benton County are road closures limiting access/egress to/from some areas, especially roads to higher elevations. Winter storms with heavy wet snow or high winds and ice storms may also result in power outages from downed transmission lines and/or poles. Average annual snowfalls in Benton County are generally low as shown below in Table 7.6. Table 7.6 Snowfall Data for Selected Cities in Benton County Location Average Annual Snowfall (inches) Lowest Annual Snowfall (inches) Highest Annual Snowfall (inches) Period of Record Corvallis 6.10 0.00 51.90 (1949-50) 1889-2004 Alsea Fish Hatchery 5.50 0.00 60.60 (1968-9) 1954-2004 www.wrcc.dri.edu Data for Corvallis (OSU) and Alsea Fish Hatchery weather stations from Western Regional Climate Center website: However, some locations in the mountainous areas of western Benton County may have higher annual snowfalls, albeit with weather station data (as is true with rainfall, as noted previously after Table 7.1). Since 1889, there have been nine years with 20? or more of snow in Corvallis, as shown below in Table 7.7. 7-15 Table 7.7 Significant Snowfall Events for Corvallis Year Annual Snowfall (inches) Peak Snowfall Month Peak Monthly Snowfall (inches) 1892-3 21.0 January 17.0 1908-9 23.0 January 23.0 1915-6 25.6 January 22.4 1919-20 20.0 December 20.0 1942-3 20.0 January 18.0 1949-50 51.9 January 51.9 1968-9 27.7 January 24.0 1970-1 27.5 January 15.3 1991-2 26.3 February 15.0 Western Regional Climate Center website: www.wrcc.dri.edu Corvallis Data for Corvallis (OSU) weather station from In addition to snow events, Benton County is also subject to ice storm and freezing rain events. Ice storms and freezing rain are fairly common, especially along the Willamette River Valley when cold air near the ground coincides with warm moist air at higher altitudes. The National Climatic Data Center (NCDC) database shows two ice storm or freezing rain events for Benton County between 1993 and 2004. Both of these were relatively minor events with increased traffic accidents due to ice on the roads, with few other damages. Website addresses for NCDC and the state and county storm event database are: www.ncdc.noaa.gov and http://www4.ncdc.noaa.gov/cgi-win/wwcgi.dll?wwevent~storms, respectively. Probabilistic ice storm data showing ice thicknesses with return periods from 50 years to 400 years are given in a recent draft report for FEMA and the National Institute of Building Sciences: Extreme Ice Thicknesses from Freezing Rain (Kathleen F. Jones, US Army Corps of Engineers, Cold Regions Research and Engineering Laboratory, May 28, 2004). The 50-year return period ice thickness map (Figure 7.8 below) shows about 0.5? of ice for Benton County, with ice thickness decreasing westward from the Willamette River Valley. 100-year and 400-year ice thicknesses for Benton County are about 0.75? and 1.0?, respectively. 7-16 Figure 7.8 50-Year Ice Thickness from Freezing Rain For Benton County, ice thicknesses in 50-year or more severe events are high enough (0.5? or greater) to cause substantial damage, especially to trees and utility lines. 7.5 Other Severe Weather Events The National Oceanic and Atmospheric Administration (NOAA), which includes the National Weather Service, also includes the National Climatic Data Center (NCDC). The NOAA and NCDC websites have a vast amount of historical information on severe weather events throughout the United States. These databases can also be searched by State and County to obtain more localized information. Website addresses are: www.noaa.gov and www.ncdc.noaa.gov, for NOAA and NCDC, respectively. The state and county storm event database can be found at: http://www4.ncdc.noaa.gov/cgi-win/wwcgi.dll?wwevent~storms. Unless otherwise referenced, all of the storm event data below for Benton County are from the state and county storm event database referenced above. 7-17 Severe Thunderstorms and Hail Events The NCDC database lists 6 thunderstorm and high wind events in Benton County since 1982. Damage was reported in only one thunderstorm event on May 1, 1998 in Corvallis; this event included numerous tree falls and damage to at least one building. Most thunderstorm events in Benton County are typically too minor to be recorded as significant storm events. Nevertheless, thunderstorm events in Benton County can occasionally cause locally high winds with tree falls that may affect roads, utility lines, and buildings. The NCDD database listed two hail events for Benton County : April 2, 2001 in Corvallis and Albany. No damage reports were available. Hail events certainly occur in Benton County, generally during summer months. However, hail damage is generally minor and few practical mitigation alternatives are applicable to hail, other than taking shelter and moving vehicles to garages when possible. Lightning Nationwide, lightning is the number two weather related killer nationwide, second only to floods. NOAA data show that lightning causes about 90 deaths per year, with at least 230 injuries (NOAA Technical Memorandum NWS SR-193, 1997). Lightning injuries appear to be systematically underreported and thus the actual injury total is most likely significantly higher. For Oregon, casualties from lightning are very low, with totals of only 7 deaths and 19 injuries reported over a 35-year period (NOAA). Thus, the level of risk posed by lightning strikes in Benton County, while not zero, is very low. For Benton County, the NCDD database does not list any major lightning events. Public education about safe practices during electrical storms is the only available mitigation measure to reduce casualties from lightning. Lightning strike damage to buildings or infrastructure is generally relatively minor and few practical mitigation alternatives are applicable to lightning, other than installing lightning arrestors on critical facilities subject to lightning damage. Tornadoes Tornadoes also occasionally occur in Oregon. However, Oregon is not among the 39 states with any reported tornado deaths since 1950. A compilation of historical tornadoes in Oregon by the national weather service (http://nimbo.wrh.noaa.gov/ Portland/tornado.html) includes 64 tornadoes statewide, with only one tornado in Benton County. On January 20, 1953 a small tornado affected portions of Corvallis with about $500,000 in damage. Several other tornadoes have occurred in nearby counties, including Clatsop and Multnomah. 7-18 The NCDC database lists a small tornado about 15 miles west of Albany on June 1, 1997 and a funnel cloud (which did not touch down) west of Corvallis on May 29, 1996. Climate and weather conditions in Oregon and specifically in Benton County make the occurrence of major tornadoes unlikely. The most practical mitigation actions for tornadoes are public warnings and taking shelter to minimize the potential for deaths and injuries. 7.6 Winter Storm Risk Assessment Winter storm flooding and wind impacts may affect both infrastructure and buildings. Localized flooding from winter storms very commonly affects the transportation system, especially roads. Severe winter storms will result in numerous road closures due either to washouts or due to depth of water on road surfaces. Such localized flooding also affects buildings located in the flooded areas. Additional road closures are likely in some events from landslides/mudslides as well as from snow/ice storms. Wind impacts from winter storms arise primarily from tree falls, which may affect vehicles and buildings, to some extent, but whose primary impact is often on utility lines, especially electric power lines. Widespread wind damages may result in widespread downing of trees or tree limbs with resulting widespread downage of utility lines. Such tree-fall induced power outages affect primarily the local electric distribution system, because transmission system cables are generally less prone to tree fall damage because of design and better tree-trimming maintenance. In severe windstorms, direct wind damage or wind driven debris impacts on buildings cause building damages, especially for more vulnerable types of construction such as mobile homes. As discussed above in Section 7.1, both winter storm flood hazards and winter storm wind hazards have highly localized impacts. The location and severity of such impacts depend very strongly on specific local conditions. Therefore, it is difficult to make regional risk assessment or loss estimates from mapping the hazards and overlaying the inventory: such a risk assessment simply requires too much detailed data that are not yet available. An alternative approach is to document the severity and locations of winter storm flood and wind damage from the pattern historical events. This approach is illustrated by the brief narratives above for selected winter storm events in Benton County. For more quantitative risk assessment of localized flooding and wind damages arising from winter storms, the best approach is to systematically gather data on sites of repetitive damages due to localized flooding or wind damages. By documenting (and mapping using GIS) the sites of repetitive damage events, along documentation of the type and cost of damages and losses, the most seriously impacted sites can be clearly identified. Clearly, such repetitive loss sites with significant damages are likely candidates for mitigation actions. 7-19 The probable impacts of winter storms on Benton County are summarized below in Table 7.9. Table 7.9 Probable Impacts of Winter Storms on Benton County1 Inventory Probable Impacts Portion of Benton County Affected Entire county may be affected by road closures or loss of electric power; otherwise direct damages to buildings and infrastructure are likely to be localized and relatively minor Buildings Isolated minor damage from tree falls, some buildings affected by flood damage in major storms, especially in the storm water drainage problem areas identified in Section 6.3 Streets within communities Minor road closures due to tree falls and flooding; limited impact because of short detour routes within communities Roads within and to/from Benton County Potential closures of some roads and major highways due to snow, debris flows or landslides, localized flooding and tree falls Electric Power Loss of electric power may be localized due to tree falls on local distribution lines or affect larger areas if tree falls affect transmission lines Other Utilities Generally minor or no impacts on other utilities from winter storms Casualties Small potential for casualties (deaths and injuries) from tree falls, contact with downed power lines, or traffic accidents. 1 These winter storm impacts include localized flooding and the effects of wind, snow, and ice. 7.7 Mitigation of Winter Storm Impacts Potential mitigation projects for winter storms may address any of the aspects of such storms, including floods, winds, and landslides (see Chapter 8). See also Chapter 13 for additional discussion of the disruptions to utility and transportation systems. For winter storm flooding, the mitigation measures discussed in Chapter 6 (Floods) for local storm water drainage flooding are exactly the mitigation measures for the flood aspects of winter storms. Common mitigation projects include: upgrading storm water drainage systems, construction of detention basins, and structure-specific mitigation measures (acquisition, elevation, flood proofing) for flood-prone buildings. For roads subject to frequent winter storm flooding, possible mitigation actions include elevation of the road surface and improved local drainage. For utilities subject to frequent winter storm flooding, possible mitigation actions include improved local drainage, elevation or relocation of the vulnerable utility elements to non-flood prone areas nearby. For wind effects of winter storms, the most common and most effective mitigation action is to increase tree-trimming effects, because a high percentage of wind damage to utilities, buildings, vehicles, and people arises from tree falls. Trimming of trees subject to falling on utilities, buildings, vehicles, and people is an effective mitigation measure. However, 7-20 economic, political and esthetic realities place limits on tree trimming as a mitigation action. Future windstorm damage in Benton County could be almost eliminated by cutting down all large trees along roads or in populated areas. Obviously, such an extreme mitigation measure is neither practical nor desirable for many reasons. Effective tree trimming mitigation programs focus on limited areas where tree falls have a high potential to result in major damages and economic losses. High priority areas include examples such as the following: 1) Transmission lines providing electric power to the area, 2) Major trunk lines providing the backbone of the electric power distribution system within the area 3) Distribution lines for electric power to critical facilities in the area, 4) Specific circumstances where falling of large trees poses an obvious threat to damage buildings and/or people or close major transportation arteries. Mitigation measures for snow and ice are limited, although tree trimming efforts, discussed above under wind, also reduce the impact of snow and ice on trees, roads, and utility lines. For the most part, dealing with snow and ice storms are primarily issues of emergency planning, response and recovery. Similarly, few mitigation measures appear practical for Benton County for other types of severe weather, including severe thunderstorms, hail, lightning, and tornadoes. For such weather events, public education about safe practices and emergency planning, response and recover appear to be the most useful pragmatic actions. The following table contains winter storm mitigation action items from the master Action Item table in Chapter 4. 7-21 7-22 This Page Left Blank . Table 7.10 Winter Storm Mitigation Action Items Mitigation Plan Goals Addressed Hazard Action Item Coordinating Organizations Timeline Life Safe Critical Facilities and Eme Services Protect Property Disaster Resilient Econo Public Education, Outr Partner Winter Storms Mitigation Action Items Short-Term #1 Complete the inventory of locations in Benton County subject to frequent storm water flooding Benton County Roads, GIS, cities Ongoing X X X X X Short-Term #2 Enhance tree-trimming efforts especially for transmission lines and trunk distribution lines. BPA, Consumers Power, PP&L, local PUDs Ongoing X X X X X Short-Term #3 Encourage prudent tree planting (avoid service lines) and safe, professional tree trimming where necessary Community Development Ongoing X X X Short-Term #4 Ensure that all critical facilities in Benton County have backup power and emergency operations plans to deal with power outages Emergency Management, Benton County Facilities, Benton County Hazard Mitigation Steering Committee 1-2 Years X X Long-Term #1 For locations with repetitive flooding and significant damages or road closures, determine and implement mitigation measures such as upsizing culverts or storm water drainage ditches Benton County Roads and Engineer, cities Ongoing X X X X X Long-Term #2 Consider upgrading lines and poles to improve wind/ice loading, under grounding critical lines, and adding interconnect switches to allow alternative feed paths and disconnect switches to minimize outage areas BPA, Consumers Power, PP&L, local PUDs 5 Years X X X X X Long-Term #3 Encourage new developments to include underground power lines Benton County Community Development, cities ongoing X X X X X 7-23 This Page Left Blank 7-24 8.0 LANDSLIDES 8.1 Landslide Overview and Definitions The term ?landslide? refers to a variety of slope instabilities that result in the downward and outward movement of slope-forming materials, including rocks, soils and artificial fill. Four types of landslides are distinguished based on the types of materials involved and on the mode of movement. These types of landslides are illustrated in Figures 8.1 to 8.4 and described below. Rockfalls are abrupt movements of masses of geologic materials (rocks and soils) that become detached from steep slopes or cliffs. Movement occurs by free-fall, bouncing and rolling. Falls are strongly influenced by gravity, weathering, undercutting or erosion. Rotational Slides are those in which the rupture surface is curved concavely upwards and the slide movement is rotational about an axis parallel to the slope. Rotational slides usually have a steep scarp at the upslope end and a bulging ?toe? of the slid material at the bottom of the slide. . Rotational slides may creep slowly or move large distances suddenly. Translational Slides are those in which the moving material slides along a more or less planar surface. Translational slides occur on surfaces of weaknesses, such as faults and bedding planes or at the contact between firm rock and overlying loose soils. Translational slides may creep slowly or move large distances rather suddenly. Debris Flows (also called debris torrents) are surficial movements in which loose soils, rocks and organic matter combine with entrained water to form slurries that flow rapidly downslope or within a stream channel. They may travel hundreds to thousands of feet. All of these types of landslides may cause road blockages by dumping debris on road surfaces or road damages if the road surface itself slides downhill. Utility lines and pipes are prone to breakage in slide areas. Buildings impacted by slides may suffer minor damage from small settlements or be completely destroyed by large ground displacements or by burial in slide debris. Also, as evidenced by 1996 winter storms in Oregon, landslides may also result in injuries or fatalities. There are three main factors that determine susceptibility (potential) for landslides: 1) slope steepness, 2) soil/rock characteristics or landform shape, and 3) subsurface water. 8-1 Loose, weak rock or soil is more prone to landslides than is more competent rock or dense, firm soils. For landslides, the term competent rock means solid, coherent rock with good bearing strength that is less prone to landslides. Finally, water saturated soils or rock with a high water table are much more prone to landslides because the water pore pressure decreases the shear strength of the soil and thus increases the probability of sliding. Figures 8.1 to 8.4 Major Types of Landslides 8-2 8-3 The water content of soils/rock is a major factor in determining the likelihood of sliding for any given slide-prone location. Thus, the vast majority of landslides happen during rainy months, when soils are saturated with water. Landslides may happen at any time of the year. In addition to landslides triggered by a combination of slope stability and water content, earthquakes may also trigger landslides. Areas prone to seismically triggered landslides are generally the same as those prone to ordinary (i.e., non-seismic) landslides. As with ordinary landslides, seismically triggered landslides are more likely for earthquakes that occur when soils are saturated with water. Debris flows and landslides are a very common occurrence in hilly areas of Oregon, including portions of Benton County. Many landslides occur in undeveloped areas and thus may go unnoticed or unreported. For example, DOGAMI conducted a statewide survey of landslides from four winter storms in 1996 and 1997 and found 9,582 documented landslides, with the actual number of landslides estimated to be many times the documented number. For the most part, landslides become a problem only when they impact developed areas and have the potential to damage buildings, roads, or utilities. 8.2 Landslide Hazard Assessment for Benton County The February 1996 winter storm contributed to landslides throughout western Oregon, including Benton County. The February storm was an intense, long duration rainfall event that was preceded by long periods of winter rainfall and a heavy snowfall in the mountains. A tropical jet stream flow brought intense warm rain that melted the snow, which contributed to the timing and runoff from the already wet soil. This resulted in numerous slope failures on slopes that were already slide-prone. The following maps show various areas within Benton County with high potential for landslides or debris flows, areas mapped as active slides, or areas with a history of repetitive slides. ? Landslide hazards to roads. This map, prepared after the 1996 winter storms, shows about 10 areas identified as repetitive landslide areas for roads in Benton County. This list of landslide problem areas is not complete. ? Oregon Department of Forestry (ODF) debris flow hazard map showing areas with high or moderate potential for debris flows: Benton County. ? Oregon Department of Forestry (ODF) debris flow hazard map showing area with high or moderate potential for debris flows, more detailed maps for o North Corvallis, Adair, North Albany o Corvallis, Philomath o Summit, Blodgett, Wren o Bellfountain, Alpine, Monroe o Alsea ? DOGAMI earthquake-Induced landslide hazard map. ? DOGAMI active slide areas in North Corvallis (just outside the Urban Growth Boundary). 8-4 ODF Debris Flow Hazard Areas Benton County 1 Oregon Department of Forestry, Western Oregon Debris Flow Maps, 1-14-99. 8-5 ODF Debris Flow Hazards North Corvallis, Adair, North Albany 1 I 1 Oregon Department of Forestry, Western Oregon Debris Flow Maps, 1-14-99. 8-6 ODF Debris Flow Hazards Corvallis, Philomath 1 1 Oregon Department of Forestry, Western Oregon Debris Flow Maps, 1-14-99. 8-7 ODF Debris Flow Hazards Summit, Blodgett, Wren 1 1 Oregon Department of Forestry, Western Oregon Debris Flow Maps, 1-14-99. 8-8 ODF Debris Flow Hazards Bellfountain, Alpine, Monroe 1 1 Oregon Department of Forestry, Western Oregon Debris Flow Maps, 1-14-99. 8-9 ODF Debris Flow Hazards Alsea Vicinity 1 Oregon Department of Forestry, Western Oregon Debris Flow Maps, 1-14-99. 8-10 DOGAMI Earthquake-Induced Landslide Hazard Map Benton County 1 Preliminary Earthquake Hazard and Risk Assessment and Water-Induced Landslide Hazard in Benton County, Oregon. rt O-01-05, 2001) (Zhenming Wang, Gregory Graham, and Ian Madin, DOGAMI, Open File Repo 8-11 8-12 DOGAMI Preliminary Map of Active Slide Areas in North Corvallis Area Preliminary Landslide Hazard Map of the Corvallis-Philomath Urban Areas, Benton County, Oregon (Ian Madin, DOGAMI). ODF Study of 1996 Winter Storm Landslides The Oregon Department of Forestry conducted a 3-year study of the impacts and landslides for two 1996 winter storms (ODF, Storm Impacts and Landslides of 1996: Final Report, June, 1999). This highly technical study is primarily focused on identifying specific slope and forest characteristics that relate to probabilities and severities of landslides. The ODF study included eight study areas, none of which was in Benton County. This ODF study provides important technical data on landslides, but does not provide a detailed inventory of landslide prone areas in Benton County. This study is thus of limited use for mitigation planning purposes, except for enhancing understanding of factors which govern landslides. General conclusions drawn from the ODF study include the following. The highest hazard for shallow rapid landslides in western Oregon occurs on slopes of over 70% to 80% steepness (depending on landform and geology). There is a moderate risk of these landslides on slopes of between 50% to 70%. Landslides that entered stream channels during the storms of 1996 typically occurred in very steep landscapes, or adjacent to stream channels. Even landslides that initiate as relatively small debris slides can mobilize into debris flows that mobilize large volumes of material and move long distances. Landslide characteristics vary greatly according to local landscape and geologic factors. Debris flows that were not initiated by up- slope landslides were uncommon. A debris flow occurs when landslides move downslope, scouring or partially scouring soils from the slope along its path. DOGAMI Earthquake?Induced Landslide Maps For Benton County, the Oregon Department of Geology and Mineral Industries (DOGAMI) has produced hazard maps for earthquake-induced landslides for many communities in Oregon, but not for any communities in Benton County. Areas prone to earthquake-induced landslides are generally also prone to non-earthquake induced landslides as well. However, these DOGAMI maps have low spatial resolution, with large areas of significant slope characterized as moderate or high landslide potential. These maps identify only a limited number of specific locations of active slides. It is important to note that while an earthquake may trigger numerous landslides, the return interval of major earthquake-induced landslides may be several hundred years, while the return interval for major storm-induced landslides may be only about 10 years. Therefore, for Benton County the probability of occurrence for major storm-induced landslides greatly exceeds that for earthquake-induced landslides. NOAA/Oregon Climate Service Debris Flow Maps ODF and the Oregon Climate Service have prepared debris flow maps for all counties in western Oregon, including Benton County. These maps show numerous areas within Benton County subject to debris flows. The six ODF maps shown above are examples of these maps. 8-13 Benton County Landslide Hazard Map Ideally, a county-wide landslide hazard map for all types of landslides could be developed for Benton County, using the existing maps described above, slope data, rainfall data, soil/rock data, as well as historical data on active slide areas. However, such a countywide map does not currently exist. More detailed landslide hazard assessment at specific locations requires a site-specific analysis of the slope, soil/rock and groundwater characteristics at a specific site. Such assessments are often conducted prior to major development projects in areas with moderate to high landslide potential, to evaluate the specific hazard at the development site. 8.3 Landslide Risk Assessment for Benton County In this section, we review a methodology for estimating landslide losses due to winter storm induced landslides. Winter storms with intense rainfalls are the most common trigger for landslides in Oregon, including landslides within Benton County. Major storms with intense rainfall can result in numerous landslides in slide-prone areas. Of course, at any given slide-prone location, landslides can occur with or without winter storms, but such occurrences are isolated and not likely to result in the type of fairly widespread landslide impacts that are possible during winter storms. Earthquakes can also trigger widespread landslides, especially if the earthquake occurs during the rainy season when soils are saturated. However, since the probability of storm-induced landslides is greater than that for earthquake-induced landslides, it makes sense to focus mitigation efforts on storm related landslide hazards. (See Chapter 10 (Earthquakes) for further commentary on earthquake-triggered landslides.) As with any risk assessment, a quantitative landslide hazard assessment requires overlay of landslide hazard (frequency and severity of landslides) with the inventory exposed to the hazard (value and vulnerability) by considering: 1) Extent of landslide susceptible areas, 2) Inventory of buildings and infrastructure in landslide susceptible areas, 3) Severity of winter storm event (inches of rainfall in 24 hours), 4) Percentage of landslide susceptible areas that will move and the range of movements (displacements) likely, and 5) Vulnerability (amount of damage for various ranges of movement). For Benton County, many high landslide potential areas are in hilly-forested areas. Landslides in these areas may damage or destroy some timber and impact logging roads. Many of the major highways in Benton County are at risk for landslides at one or more locations with a high potential for road closures and damage to utility lines. Especially in the western portions of Benton County, with a limited redundancy of the road network, such road closures may isolate some communities. In addition to direct landslide damages to roads 8-14 and highways, affected communities are also subject to the economic impacts of road closures due to landslides, which may disrupt access/egress to/from communities. The potential impact of debris flows and landslides on Benton County are summarized below in Table 8.5. Table 8.5 Potential Impacts of Debris Flows and Landslides on Benton County Inventory Probable Impacts Portion of Benton County affected Landslides and debris flows are possible in any of the higher slope portions of Benton County, including much of the western portion of the county. Landslide prone areas also include portions of the hilly areas west of Corvallis and limited portions of the North Albany area. Buildings Buildings at high risk include those situated below steep slopes or at the mouth of drainage basins. Most buildings in landslide potential areas are residential; the inventory of landslide prone buildings (including critical facilities) in Benton County is not yet determined. Streets within communities Minor road closures possible from landslides; limited impact because of short detour routes within communities. Roads within and to/from Benton County Potential closures of some major highways and secondary roads due to landsides/ Potential to isolate communities, especially in the western portions of the county, inlcuding major routes such as Highway 20 and Highway 34. Electric power Potential for localized loss of electric power due to landslides affecting power lines in or near Benton County Other Utilities Potential outages of water, wastewater and natural gas from pipe breaks from landslides. Probable impacts are very localized. Casualties Landslides that impact buildings or roads could result in a small number of casualties (deaths and injuries) 8.4 Mitigation of Landslide Risk In terms of public safety there are two broad types of landslides to be concerned about: 1) those that can be sometimes be solved by engineering methods (such as road fill failures and slow moving landslides, and 2) those that can typically only be solved through prudent location of buildings, roads, and utilities (debris flows, debris torrents). It is important to make this distinction to understand that some landslide problems do not lend themselves to engineering solutions. Mitigation of landslide risks is often quite expensive. In some cases, slope stability can be improved by addition of subsurface drainage to reduce pore water pressure, by construction of appropriate debris dams, retaining walls or by other types of geotechnical remediation. In some cases, buildings can be hardened to reduce damages. An alternative mitigation 8-15 8-16 strategy for already built buildings or infrastructure with high potential for landslide losses is to relocate the facilities outside of known slide areas. Mitigation of landslide risk can also be accomplished by effective land use planning to minimize development in slide-prone areas. Generally, such land use planning requires rather detailed geotechnical mapping of slide potential so that high hazard areas can be demarcated without unnecessarily including other areas of low slide potential. The impacts of slide damage on road systems can also be partially addressed by identifying areas of high slide potential or of repetitive past slide damages so that alternative routes for emergency response can be pre-determined. An example of a landslide mitigation project in Lane County is given below. This location has been subjected to road closures due to rockfalls from a steep slope. Construction for this project was scheduled to begin in August 2004. Similar landslide mitigation projects may be possible for some slide-prone locations in Benton County. The following table contains landslide mitigation action items from the master Action Items table in Chapter 4. Table 8.6 Landslide Mitigation Action Items Mitigation Plan Goals Addressed Hazard Action Item Coordinating Organizations Timeline Life Safe Critical Facilities and Emergen Serv Protect Property Disaster Resilient Econo Public Education, Outr Partner Landslide Mitigation Action Items Short-Term #1 Complete the inventory of locations where critical facilities, other buildings and infrastructure are subject to landslides Benton County GIS, cities (public works) 1-2 Years X X X X X Long-Term #1 Consider landslide mitigation actions for slides seriously threatening critical facilities, other buildings or infrastructure Benton County Engineer, Community Development, cities, special districts 5 Years X X X X X Long-Term #2 Limit future development in high landslide potential areas by adopting landslide development practices that minimize landslide potential Benton County Community Development Ongoing X X X X X 8-17 This Page Left Blank 8-18 9.0 WILDLAND/URBAN INTERFACE FIRES Fire has posed a threat to mankind since the dawn of civilization. Fires may cause significant damage to property and may also result in deaths and injuries. For the purposes of mitigation planning, we consider three types of fires: structure fires, wildland fires, and wildland/urban interface fires. Structure fires are fires in urban, suburban or rural areas where structures (and contents) are the primary fire fuel. Structure fires predominantly affect residential and other ordinary buildings. However, structure fires may also affect other types of structures, including bulk fuel storage or HAZMAT facilities. Fires affecting these types of facilities may be particularly hazardous to both firefighters and nearby residents. Fires on pipelines and transportation fires (road, rail, air) generally have similar characteristics to fires at HAZMAT sites or structures. Wildland fires are fires where vegetation (grass, brush, trees) is the primary fire fuel. Wildland/urban interface fires are fires where the fire fuel includes both structures and vegetation. This chapter considers all types of fires. However, the emphasis is on wildland/urban interface fires because such fires are analogous to natural disasters in that they may affect large developed areas and large numbers of people. Thus, wildland/urban interface fires are of special concern for mitigation planning. Most structure fires are limited to one structure. Structure fires involving bulk fuel, hazardous materials, pipelines, and transportation fires have many similarities in response strategies and impacts to the more general discussion of Hazmat Incidents, as discussed in Chapter 14. Wildland fires, by definition, affect wildlands with generally limited impacts on developed areas. In 1999, according to National Fire Protection Association (NFPA) data there were over 30,000 fire agencies in the United States. Nearly 90% of these are all volunteer or mostly volunteer fire districts with only about 11% being career or mostly career fire fighting agencies. However, the career fire agencies tend to serve large communities. Thus, about 60% of the total population in the United States is served by career agencies, while about 40% is served by volunteer fire districts. In Oregon, historical fire statistical data are generally good because each local fire agency is required to file reports of every fire incident with the State Fire Marshal?s Office. National fire statistics are available through the National Fire Incident Reporting System (NFIRS) that is maintained by the U.S. Fire Administration (USFA). National fire data are published by the USFA and by the National Fire Protection Association (NFPA), a private association. THE NFIRS database contains incident reports from 49 states and over 11,000 fire agencies and includes about one-third of all reported fires 9-1 that occur annually in the United States. Benton County includes a mix of forest, brush, grasslands, and agricultural land, as well as developed land. Vegetation patterns for lands surrounding population centers in Benton County vary, but most of the cities and the smaller rural communities have at least some forested areas in close proximity to developed areas. 9.1 Fire Primer For this section of the multi-hazard mitigation plan, the focus is on wildland/urban interface fires. However, to provide a context for the discussion of wildland/urban interface fires, we first briefly review the characteristics of all three types of fires. 9.1.1 Structure Fires Structure fires are fires in urban, suburban or rural areas where structures (and contents) are the primary fire fuel. Ever since the first volunteer fire agency was established in the United States in 1648, the primary focus of most fire agencies has been to reduce the risk of structure fires. Historically, structure fires have posed the greatest threat to both property and life safety. In dealing with structure fires, fire agencies have three primary objectives: first, minimize casualties; second, prevent a single structure fire from spreading to other structures; and third, minimize damage to the structure and contents. In recent decades, the rate of structure fires (number of fires per year per 1,000 structures) and the total number of structure fires have declined sharply even though the number of structures has increased with increasing population. This decrease in structure fires is attributed to a number of factors, most importantly better building codes that have reduced both the numbers of ignitions and the likelihood that a small fire will quickly spread. Building code improvements include better wiring, smoke detectors, better design of furnaces, reduced use of portable heating devices, and the widespread use of fire resistant materials such as sheet rock and non-flammable roofs. In addition to the building code improvements, fire suppression capabilities have also improved over the decades. Improved water systems provide greater and more reliable water flows for fire suppression efforts. Improved fixed fire protection systems including notification systems, sprinklers, and fire barriers along with better training, better communication equipment, better fire fighting equipment and apparatus have also all contributed to improved fire suppression capabilities. Widespread use of smoke detectors has also reduced the number of casualties by providing occupants more warning time for evacuation. In recent decades, a decline in the percentage of smokers in the United States has also had a beneficial impact on the rate of accidental ignitions from careless handling of smoking materials. 9-2 The decrease in the number of structure fires in recent decades has been accompanied by a corresponding decrease in the numbers of deaths from structure fires as shown below in Table 9.1. Table 9.1 Recent History of Fire Deaths in the United States U.S. Oregon 1980 5,809 50 1990 4,162 33 2000 4,045 42 2002 3,380 45 Fire Deaths1Year 1 Fire deaths are as estimated by the National Fire Protection Association (www.nfpa.org), with 2000 and 2002 Oregon data from Oregon Office of State Fire Marshal. Despite the dramatic reductions over the decades, structure fires still cause a great deal of damage and many casualties. NFPA estimates for 2002 are that structure fires caused about 3,380 deaths and $10 billion in property damage. In addition to dealing with structure fires, urban, suburban and rural fire agencies also deal with other common types of fires including vehicle fires, trash fires, and small debris or vegetation fires. For 2002, NFPA estimates for total fire agency responses to fires are as summarized below in Table 9.2. Table 9.2 2002 NFPA Fire Statistics Type of Fire Fire Agency Responses Structure Fires 519,000 Vehicle Fires 329,500 Fires Outside Structures 71,000 Rubbish Fires 204,000 Wildland Fires 399,000 All Other Fires 165,000 TOTAL 1,687,500 The complete NFPA fire statistics estimates are given in their report ?Fire Loss in the 9-3 United States During 2002,? that is downloadable from their website (www.nfpa.org). Additional data are available at the USFA website (www.usfa.fema.gov). 9.1.2 Wildland Fires Wildland fires are fires where vegetation (grass, brush, or trees) is the primary fire fuel. Wildland fires in Oregon typically occur in national or state forests and parks or in forest tracts of private land that may be owned by forest industries or by other private owners. By definition, wildland fires generally involve few or no structures. Fires that involve a mixture of vegetation and structures are considered wildland/urban interface fires and are discussed below in Section 9.1.3. Fire suppression strategy for wildland fires is significantly different than for structure fires. For wildland fires, the most common suppression strategy is to contain the fire at its boundaries, to stop the spread of the fire and then to let the fire burn itself out. Fire containment typically relies heavily on natural or manmade firebreaks. Water and chemical fire suppressants are used primarily to help make or defend a firebreak, rather than to put out an entire fire, as would be the case with a structure fire. Fires that are purely wildland fires, without threatening structures, nevertheless cause loss of timber resources and environmental and ecological damage. Wildland fires kill wildlife and damage habitat. Areas that have burned are also subject to erosion and landslides due to loss of ground cover. These effects also may negatively impact water quality by increasing turbidity. Wildland fires also may result in large fire suppression costs, with a potential for casualties among firefighting personnel. Historically, fire suppression strategy for wildland fires has generally been to try to minimize the acreage burned in each wildland fire, by applying the maximum available fire suppression resources and trying to contain each fire as quickly as possible. In recent years, however, fire suppression strategy for wildland fires in federal forests has evolved substantially in two important aspects. First, to a greater extent than previously, wildland fires are being recognized as part of the natural ecology and natural life cycles of wildlands. Fires create open spaces with different habitats for both plants and animals than existed previously. Second, the emphasis on maximum suppression of wildland fires has resulted in many fires being smaller than would naturally occur. Because of the reduction in frequent, smaller fires, many wildland areas have developed extraordinarily high fuel loads. Thus, the potential for very large, catastrophic wildland fires may actually be increased by the effective suppression of smaller fires. In recent years, evolving strategies for dealing with wildland fires have focused more attention on fuel management. Strategies include more controlled burns and greater tolerance for allowing smaller fires to burn, with the objective of reducing fuel loads of smaller vegetation and thus reducing the potential for larger fires. The above fire strategies are most applicable to lands managed as wilderness of natural areas. Fire protection strategies for commercial forest lands focus more on the value of wood fiber and thus fire protection for such areas is intended to minimize acreage 9-4 burned and therefore to minimize value lost. The value protected is both the market value of the standing timber and the lost opportunity if a stand of timber is lost. Wildfires may be started by natural causes, such as lightning strikes. US Forest Service data for the United States indicate that lightning starts about 13% of wildfires. About 25% of wildfires are arson, while the rest are due to a variety of manmade causes including debris burns, discarded smoking materials, sparks from vehicles, sparks from power lines and so on. In Benton County, because of local weather conditions, the proportion of fires started by lightning is likely to be significantly lower than the national data referenced above. Wildfire hazard depends on three main factors: vegetative fuel load, weather, and topography. There are several parameters that define the fire potential of vegetation. Vegetative fuel loads are typically expressed as tons per acre. The greater the amount of fuel loading the greater the amount of energy that will be released in a fire. Vegetative fuels are also classified by burn index, which is a measure of the amount of energy per pound of fuel. Fuels may also be classified by potential duration of burning. For example, wildfires fueled by grass may spread very quickly, but grass contains relatively little fuel energy and tends to burn out quickly. Wildfires fueled by larger vegetation may spread more slowly, but larger vegetation contains more fuel energy and tends to burn for a longer duration. Moisture content of vegetative fuels is also a major determinant of wildland fire potential. The lower the moisture content the greater the fire potential. Moisture content at any given time depends on antecedent (before the given time) weather conditions. The moisture content of larger fuels (e.g., trees) depends on previous weather conditions over periods of several weeks or even months. The moisture content of smaller fuels (brush) depends on previous weather conditions over several days or a week or two. The moisture content of very small fuels (e.g., grasses ) depends largely on previous weather conditions over a few hours or a day or two. The fire hazard posed by vegetative fuel loads also depends on fuel continuity, both horizontally and vertically. Horizontal continuity, the distribution of fuels over the landscape, strongly affects the spread and containment of wildfires in a given geographic area. Vertical continuity of fuels, the linkage between fuels at ground level and tree crowns, also affects the fire potential. Forests with strong ladder fuels (understory growth between ground fuels and tree crowns) are more likely to have major fires involving tree crowns. Forests with limited ground fuels and little or no ladder fuels are much more likely to experience minor ground fires without a fire involving tree crowns. Weather also has a profound impact on wildland fire potential. Weather conditions of high temperatures, low humidity, and high winds may greatly accelerate the spread of a wildland fire and make containment difficult or impossible. Changes in weather conditions can greatly accelerate a fire?s spreading rate. Many casualties have 9-5 occurred when firefighting personnel are trapped by sudden bursts of fire spread in response to changes in wind conditions. For many larger fires, containment is possible only with a little help from mother nature via lower temperatures, reduced winds or significant rainfall. Local topography is also a major factor in the spread of wildfires. Fires burn much more quickly up slope than they do down slope. Doubling a slope approximately doubles the rate of fire spread. Canyons, gulches and other local topographic effect can act as chimneys, intensifying fires in certain areas. Fires tend to slow at ridge tops and thus ridge tops are often chosen as locations for firebreaks. Suppression of wildland fires depends on the three main factors - vegetative fuel load, weather, and topography - that, in combination, govern fire potential. High fuel loads, hot, dry, windy weather and steep slopes increase fire potential and make fire suppression much more difficult. Conversely, low fuel loads, cool, moist weather with low winds, and gentle slopes make fire suppression easier. In addition, however, fire suppression also depends on two other important factors: availability of fire suppression resources and access. Fire suppression resources include firefighting personnel, equipment and apparatus, as well as water and chemical fire suppressants. The greater the availability of fire suppression resources, the more likely it is that a given fire will be contained quickly. Fire suppression also depends on access. Fires in remote areas without ground access via roads are more difficult to fight and thus harder to contain than are fires with better access for fire suppression crews and apparatus. Access and therefore effective response is partially a function of land management objectives. Lands managed for natural conditions (wilderness) where roads have not been built or the existing roads have been vacated, tend to have a much poorer fire suppression response than commercial forestlands where road systems are maintained. In the 1930s, wildfires consumed an average of 40 to 50 million acres per year in the contiguous United States, according to US Forest Service estimates (US Forest Service, Managing the Impact of Wildfires on Communities and the Environment, September 8, 2000). By the 1970s, the average acreage burned had been reduced to about 5 million acres per year. Over this time period, fire suppression efforts were dramatically increased and firefighting tactics and equipment became more sophisticated and effective. For the 11 Western states, the average acreage burned per year since 1970 remained relatively constant at about 3.5 million acres per year. However, because of this pattern of more effective suppression of wildland fires, the patterns and characteristics of wildland fires are changing. Vegetation species that would have normally been minimized by frequent fires became more dominant. Over time, many species have become susceptible to disease and insects, leading to an increase in dead and dying trees. The resulting accumulation of debris has created the types of fuels than promote intense, rapidly spreading fires. In many areas introduction of non-native species has also added to the fuel load. Decades old patterns of logging 9-6 and fire suppression have also changed the characteristics of forests. Older forests were typically less dense, with smaller numbers of larger, more fire-resistant trees. Newer forests are denser with larger numbers of smaller less fire-resistant trees. Younger trees have thinner bark and are more susceptible to fire injury and thus may also sustain more economic damage than an older stand. In combination these effects over the last several decades have resulted in many recent wildland fires that are hotter, faster, and larger than those experienced in the past. 9.1.3 Wildland/Urban Interface Fires Wildland/urban interface fires are fires where the fuel load consists of both vegetation and structures. In Oregon, as elsewhere in the United States, recent patterns of development have lead to increasing numbers of homes built in areas subject to wildland fires. Development in areas subject to wildland fires may pose high levels of life safety risk for occupants as well as high levels of fire risk for homes and other structures. Urban or suburban areas may have a significant amount of landscaping and other vegetation. However, in such areas the fuel load of flammable vegetation is not continuous, but rather is broken by paved areas, open space and areas of mowed, often irrigated, grassy areas with low fuel loads. In these areas, the vast preponderance of all significant fires are single structure fires. The combination of separations between buildings, various types of fire breaks, and generally low total vegetative fuel loads make the risk of fire spreading much lower than in wildland areas. Furthermore, most developed areas in urban and suburban areas have water systems with good capacities to provide water for fire suppression and organized fire agencies who typically respond quickly to fires, with sufficient personnel and apparatus to control fires effectively. Thus, in such areas the risk of a single structure fire spreading to involve multiple structures is generally quite low. Areas subject to wildland/urban interface fires have very different fire hazard characteristics. The defining characteristic of the wildland/urban interface area is that structures are built in areas with essentially continuous (and often high) vegetative fuel loads. In other words, structures are built in areas subject to wildland fires. When wildland fires occur in such areas, they tend to spread quickly and structures in these areas may, unfortunately, become little more than additional fuel sources for wildland fires. The siting of homes has also changed over time. Historically pioneering families built their homes in low lands, close to water and the fields they intended to work, while during the last 30 years or so, rural homes have increasingly been built in locations chosen because of the view or other amenities. Thus, many newer homes are in locations more difficult to defend against wildland fires. The fire risk to structures and occupants in wildland/urban interface areas is high not only because of the high vegetative fuel loads but also because fire suppression resources are typically much lower than in urban or suburban areas. Homes in wildland/urban interface areas are most commonly on wells rather than on municipal 9-7 water supplies. Thus, the availability of water for fire suppression is often severely limited. Less availability of water resources makes it more likely that a small wildland fire or a single structure fire in an urban/wildland interface area will spread before it can be extinguished. Furthermore, because many developments in interface areas have relatively low populations and are some distance from population centers, the availability of firefighting personnel and apparatus is generally lower than in more populated areas and response times are typically much longer. The longer typical response times arise in part because of greater travel distances and, thus, greater travel times, but also because most fire agencies in lower population density areas are entirely or largely composed of volunteer staff. Response times from volunteer staff fire agencies are typically longer than response times for career staff agencies, where fire stations are commonly staffed continuously. In some cases, narrow winding roads also impede access by fire fighting apparatus. As with water supplies, the lower availability of fire fighting personnel and apparatus and the longer response times increase the probability that a small wildland fire or a single structure fire in an urban/wildland interface area will spread before it can be extinguished. It is important to note however, that fire agencies in wildland/urban interface areas are often more experienced in dealing with such fires than are urban fire agencies. Furthermore, because of local placement, they are often closer to wildland/urban interface incidents than are the Oregon Department of Forestry or the U.S. Forest Service and Bureau of Land Management. Developments in urban/wildland interface areas often face high fire risk because of the combination of high fire hazard (high vegetative fuel loads) and limited fire suppression capabilities. Unfortunately, occupants in many wildland/urban interface areas also face high life safety risk. High life safety risk arises because of the high fire risk, especially from large fires that may spread quickly and block evacuation. Life safety risk in interface areas is often exacerbated by limited numbers of roads (in the worst case only one access road) that are often narrow and winding and subject to blockage by a wildland fire. Life safety risk in interface areas is also often exacerbated by homeowners? reluctance to evacuate homes quickly. Instead, homeowners often try to protect their homes with whatever fire suppression resources are available. Such efforts generally have very little effectiveness. For example, the water flow from a garden hose is too small to meaningfully impact even a single structure fire (once the structure is significantly engulfed by flames) and is profoundly too small to have any impact on a wildland fire. Unfortunately, homeowners who delay evacuation in well meant but misguided attempts to save their homes often place their lives in grave jeopardy by delaying evacuation until it may be impossible. Major fires in the urban/wildland interface have the potential for enormous destruction and very high casualties. For example, the October 20, 1991 East Bay Fire in Oakland California burned 1,600 acres with 25 fatalities, 150 injuries, and over 3300 single-family homes and 450 apartment units destroyed. Total damages were over $1.5 billion. This 9-8 fire was fueled by very high vegetative fuel loads and occurred on an unusually hot, dry, windy day. The fire spread extremely quickly, with over 800 homes engulfed by fire within the first hour, and completely overwhelmed initial fire suppression efforts. In October 1991, rural counties near Spokane Washington experienced 92 separate fires that burned about 35,000 acres and 114 homes. Between October 25 and November 3, 1993, 21 major wildland fires broke out in California. These fires burned over 189,000 acres and destroyed over 1,100 structures with 3 fatalities and hundreds of injuries. The worst wildland/urban interface fire in United States history as far as casualties are concerned occurred in 1871 in Peshtigo, Wisconsin. This fire burned over 1.2 million acres and killed over 1,200 people. In 2003, a series of wildland/urban interface fires in southern California (San Bernardino area) burned over 750,000 acres and destroyed over 3,000 homes. These few examples dramatically illustrate the potential for disasters in the urban/wildland interface area. 9.2 Measures of the Level of Fire Hazard There are several quantitative and semi-quantitative measures of the level of fire hazard. The United States Forest Service, in cooperation with other fire agencies, has developed most of these measures. National maps of these fire hazard measures are available at the Forest Service website (www.fs.fed.us). These maps are updated very frequently, in some cases daily. All of the Forest Service Fire Danger maps and related technical maps are viewable at the website by going to the INDEX category, then to Fire, Wildland Fire Assessment System. The spatial resolution of the web-published maps is relatively low. For example, the Oregon data are based on about 90 reporting stations scattered across the state. Thus, these maps are intended to show regional differences in the level of fire hazard, rather than detailed local differences. However, as a regional guide to fire hazard levels, these maps are enormously useful and readily accessible. The ODF web site (www.odf.state.or.us) has local fire danger information for Benton County, as well as any fire restrictions currently in effect. In addition, regulated use signs are also posted to inform the public and rural residents of fire restrictions due to fire danger. The most useful major fire danger measures are briefly reviewed below. For reference, we note that the Forest Service website also has an extensive glossary of fire-related terms, which may be helpful for those unfamiliar with fire terminology and nomenclature. Observed Fire Danger Class Maps The USFS fire danger class is five level fire danger classification scheme that is based largely on moisture content in fuels and weather conditions (temperature, humidity, wind). Daily nationwide maps are viewable and printable from the Forest Service website (www.fs.fed.us). This fire danger classification is widely used for purposes such as restricting campfires and outdoor burning and is widely reported in the media. 9-9 The formal definitions of the five levels of danger are given below. USFS Fire Danger Classification (with Color Codes) LOW (dark green). Fuels do not ignite readily from small firebrands, although a more intense heat source, such as lightning, may start many fires in duff or punky wood. Fires in open cured grassland may burn freely a few hours after rain, but woods fires spread slowly by creeping or smoldering, and burn in irregular fingers. There is little danger of spotting. MEDIUM (light green or blue). Fires can start from most accidental causes, but with the exception of lightning fires in some areas, the number of starts is generally low. Fires in open-cured grassland will burn briskly and spread rapidly on windy days. Timber fires spread slowly to moderately fast. The average fire is of moderate intensity, although heavy concentrations of fuel, especially draped fuel, may burn hot. Short-distance spotting may occur, but is not persistent. Fires are not likely to become serious, and control is relatively easy. HIGH (yellow). All fine dead fuels ignite readily and fires start easily from most causes. Unattended brush and campfires are likely to escape. Fires spread rapidly and short-distance spotting is common. High-intensity burning may develop on slopes, or in concentrations of fine fuels. Fire may become serious and their control difficult, unless they are attacked successfully while small. VERY HIGH (orange). Fires start easily from all causes and, immediately after ignition, spread rapidly and increase quickly in intensity. Spot fires are a constant danger. Fires burning in light fuels may quickly develop high intensity characteristics such as long-distance spotting and fire whirlwinds when they burn into heavier fuels. EXTREME (red). Fires under extreme conditions start quickly, spread furiously, and burn intensely. All fires are potentially serious. Development into high- intensity burning will usually be faster and occur from smaller fires than in the very high danger class. Direct attack is rarely possible, and may be dangerous, except immediately after ignition. Fires that develop headway in heavy slash or in conifer stands may be unmanageable while the extreme burning condition lasts. Under these conditions, the only effective and safe control action is on the flanks until the weather changes or the fuel supply lessens. In Oregon, the Oregon Department of Forestry?s four level fire danger classification is widely used. These four levels are similar to the USFS levels described above, except for the omission of the Very High classification level: LOW (green) MODERATE (blue) HIGH (yellow), and 9-10 EXTREME (red). Fire Potential Index Map This experimental product portrays a more quantitative measure of fire danger than the Fire Danger Classification map discussed above. This map is primarily of interest for fire service professionals and fire researchers. Other Maps The Forest Service website also provides several other types of technical maps which are intended for fire service professionals and fire researches. These maps and all of the more common maps summarized above can also be found at the FDR (Fire Danger Rating) web page which can be accessed via the search button on the Forest Service Home Page referenced above. 9.3 Historical Data for Wildland Fires in Oregon The Oregon Department of Forestry website (www.odf.state.or.us) has a table of the most important historical fires in Oregon over the past 150 years. Of the 12 major fires, the five largest fires all occurred between 1848 and 1868. The two largest fires, the 1868 Coos Bay fire and the 1849 Siletz fire consumed 988,000 and 800,000 acres of wildland, respectively. The next four largest fires occurred between 1933 and 1945, with each fire consuming between 240,000 and 180,000 acres. The most recent fire listed, the 1987 Silver Fire burned 97,000 acres. None of these major fires occurred in Benton County. More recent major fires include the 2002 Biscuit Fire that burned nearly 500,000 total acres (with about 471,000 acres in Oregon and nearly 29,000 acres in California) and the 2003 B&B Complex fire that burned 90,769 acres. The Oregon Department of Forestry website (www.odf.state.or.us) has several categories of wildland fire data listed, including: numbers of forest fires and numbers of acres burned in Oregon forestlands for 1986 to 2003. However, these ODF data are only for ODF-responsibility lands and do not include forestlands where primary fire suppression responsibility is federal or local. These data, which will presumably be updated from time to time, provide one measure of wildland fire data for Oregon. For ODF responsibility lands in Oregon as a whole, the 10-year average number of wildland fires is 1,062. Since 1986, the largest number of acres burned in one year was 99,060 in 2002, while the lowest number of ODF-responsibility acres burned in one year was 1,410 in 1997. For the entire state of Oregon, both the number of fires and the acres burned are higher than these ODF data alone. 9-11 9-12 The Oregon Department of Forestry website (www.odf.state.or.us) has excellent map showing forest coverage and forest type throughout Oregon. Oregon Department of Forestry data on forest ownership areas are shown below in Table 9-3 for Oregon. Table 9.3 Forest Land Ownership in Oregon Ownership Acres Percent of Total Federal 15,968,000 57.51% State 885,000 3.19% Other Public Lands 123,000 0.44% Tribal 414,000 1.49% Forest Industry 5,870,000 21.14% Other Private 4,506,000 16.23% Total 27,766,000 100.00% For Oregon as a whole, about 61% of the forestlands are public, 1.5% are tribal, with the remainder being privately owned. Of the privately owned forest land, about 57% is owned by the forest industry. Statewide, the Oregon Department of Forestry has responsibility for about 15.8 million acres of forestland, or about 57% of the total forests in Oregon. However, the overall forest ownership pattern for Benton County is roughly similar to the statewide pattern shown above in Table 9.4. Overall, Benton County is approximately 80% forested (Atlas of Oregon, Vegetation Map, University of Oregon Press, 2002). Essentially the entire western portion of the county is forested, along with much of the area along the Willamette River, except for the relatively small developed areas and relatively small areas of agricultural lands. This vegetation map is shown on the following page. Vegetation Cover in Benton County (Atlas of Oregon) 9-13 9-14 This page left blank Most of the vegetated areas in Benton County are classified as Douglas Fir ? Western Hemlock, with areas of Douglas Fir ? Broadleaf Deciduous, and areas of Douglas Fir ? Oregon White Oak and Oregon White Oak ? Douglas Fir. Along the Willamette River Valley there are areas of Cottonwood-Willow Riparian, and Pasture Riparian Bottomland, and Agricultural lands with these classifications being as per the Atlas of Oregon. Vegetation Codes for Benton County Include: dd Douglas fir ? broadleaf deciduous dh Douglas fir ? western hemlock do Douglas fir ? Oregon white oak od Oregon white oak ? Douglas fir m Marsh rc Cottonwood ? willow riparian rb Pasture ? riparian bottomland ag agricultural 9.4 Urban/Wildland Interface Fire Hazards for Benton County The United States Forest Service (Department of Agriculture), in cooperation with several agencies from the Department of the Interior, has recently published a report identifying wildland/urban interface communities within the vicinity of Federal lands that are a high risk from wildfire (Federal Register, Volume 66, pp. 43383-43435, August 21, 2001). The following two communities in Benton County have been designated as ?Interface Communities? that are within or adjacent to areas subject to serious wildfire hazards and are in the vicinity of Federal lands: Alsea and Glenbrook . The omission of other communities in Benton County from this list does not mean that they are not at risk of wildland/urban interface fires, but simply that they are not at risk and in the vicinity of Federal lands, as per the requirements for the USFS listing. Overview and Background Information As discussed above in Section 9.1, wildland/urban interface fires are wildland fires in areas where structures provide additional fuel load. Thus, the fire hazard for wildland/urban interface fires is essentially the same as the fire hazard for wildland fires. In this context, fire hazard means the probability and severity of fires. Fire risk, the threat to people and the built environment, depends on the level of fire hazard and on the extent of development in fire-prone areas. The three primary factors governing the level of hazard for wildland fires or wildland/ urban interface fires are: fuels (type and load), weather and topography. For many communities in Benton County, the fuel load in the nearby forested areas is generally high and relatively continuous across large geographic areas. Because of historical logging activities, much of the forest is composed of relatively young trees, with a high 9-15 density of trees per acre. Such forests may pose a higher fire hazard than do old growth forests with fewer, larger trees. Topography contributes to fire hazard because fires spread much more quickly up steep slopes. Weather is very important in governing the level of fire hazard. Rainfall amounts and patterns contribute to the level of fuel load and also to moisture levels in vegetation. During fires, temperature, humidity and wind speed are major factors governing the rate of spread of wildland fires and thus major factors governing the ease or difficulty with which a given fire is likely to be contained. Typical annual rainfall amounts for Benton County are moderately high to very high, with annual rainfalls ranging from about 40 inches in the Willamette Valley to as much as 140 inches in portions of the Coast Range. Wildland/urban fire hazards in Benton County would be highest during prolonged periods of drought, especially after periods of normal to above normal rainfall, which would result in a combination of high fuel loads and unusually dry conditions. Historical Fire Data The Oregon Department of Forestry (Jim Wolf) provided records for all wildland fires in ODF responsibility lands in Benton County from 1970 to 2003. These records provide an useful resource to evaluate both the historical frequency and severity of wildland fires in Benton County For this 34-year period, the ODF records show a total of 362 wildland fires for ODF responsibility lands in Benton County, or an average of about 11 fires per year. These ODF data are summarized below in Table 9.4. Table 9.4 ODF Fire Data for Benton County Benton County Total (acres) 432,640 ODF Responsibililty (acres) 298,504 ODF Responsibililty (% of county) 69.00% Total ODF Fires 362 Fires Less than 1 acre 248 Fires 1 to 9 acres 93 Fires 10 acres or more 21 Largest fire (acres) 79 ODF Fires Per Year 11 Total Acres Burned 1004 Average Acres Burned Per Year 30 ODF Fire Responsibility for Benton County ODF Fire Statistics (1970-2003) In interpreting these data, it is important to keep in mind that these data are for ODF responsibility areas only, and may not include all fires in areas covered only by local fire 9-16 departments or areas where federal agencies have fire suppression responsibility. However, for Benton County, ODF responsibility lands include about 69% of the entire county, and a higher percentage of the forested lands. The ODF data show 362 fires over the 34-year time period, or an average of 11 fires per year. The total acres burned were only 1,004 or about 30 acres per year. Most of these fires were less than one acre (248), with 93 fires between 1 and 9 acres. Only 21 fires were 10 acres or more. The largest fire reported consumed 79 acres. ODF data on Benton County fires between 1967 and 2002 are shown on the map on the following page. This map shows the location and size of all reported fires during this time period. As shown on the map, these historical data show wildland fires distributed more or less uniformly throughout the forested areas of Benton County. Ideally, historical fire data should suffice to estimate the annual probably for fires in the wildland/urban interface areas of Benton County. However, current data do not appear adequate to make credible calculations because the data for local, state, and federal responsibility areas are not commensurate and are not sortable by type of location (wildland, interface, developed areas). Nevertheless, the data reviewed above provide a general picture of the level of wildland/urban interface fire risk for Benton County overall. However, there are several reasons why the fire risk may be higher than suggested above, especially in developing wildland/urban interface areas. 1) Large fires may occur infrequently, but statistically they will occur. One large fire could significantly change the statistics. In other words, 34 years of historical data may be too short to capture large, infrequent wildland fire events. A seismic analogy is the Cascadia Subduction Zone earthquake discussed in Chapter 10. This event has not occurred in the past 30 years and probably has not occurred since 1700. Nevertheless, large earthquakes have occurred in the past and are likely in the future. Thus, a 34-year record does not completely reflect the hazard from large earthquakes or large wildland fires. 2) The level of fire hazard depends profoundly on weather patterns. A several year drought period would substantially increase the probability of large wildland fires in Benton County. For smaller vegetation areas, with grass, brush and small trees, a much shorter drought period of a few months or less would substantially increase the fire hazard. 3) The level of fire hazard in wildland/urban interface areas, with the greatest risk for life safety and property, is likely significantly higher than for wildland areas as a whole. The probability of fires starting in interface areas is much higher than in wildland areas because of the much higher population density in interface areas. Most wildland or interface fires have human sources of ignition - arson, sparks from vehicles or electric lines, discarded smoking materials, or trash or debris 9-17 fires that get out control, and so on. Thus, the probability of a given acre burning is probably higher in interface areas than for the wildland areas of Benton County as a whole. 9-18 ODF Wildfire History Data for Benton County (1967-2002) 9-19 Developments in wildland/urban interface areas face a range of levels of fire risk, depending on a number of factors. Developments that have all of most of the following attributes are at the highest level of risk: 1) High vegetative fuel loads, with a high degree on continuity of fuel load (i.e., few significant firebreaks). Risk may be particularly high if the fuel load is grass, brush and smaller trees, subject to being at very low moisture levels in short duration drought periods. 2) Higher slopes, which cause fires to spread more rapidly than in flatter terrain. 3) Limited fire suppression capacity, including limited water supply capacity for fire suppression purposes, limited fire fighting personnel and apparatus, and typically long response times for fire alarms. 4) Limited access for fire fighting apparatus and limited evacuation routes for residents at risk. 5) Construction of structures to less than fully fire-safe practices, and 6) Lack of maintenance of firebreaks and defensible zones around structures. Overall, the threat of wildland fire and/or wildland/urban interface fires appears moderate for Benton County, in large part because of the typically high levels of rainfall. However, for portions of Benton County, depending on specific conditions in developments in wildland/urban interface areas, the threat may be moderate to high, especially during periods of drought. The specific level of risk for each development depends on the risk factors as summarized above. A comprehensive evaluation of the level of risk for developments in wildland/urban interface areas requires a specific evaluation of the risk attributes listed above for each development area. 9.5 Fire Protection Service Providers and Areas with High Potential for Wildland/Urban Interface Fires Fire protection services within the developed areas of Benton County are provided by ten local agencies: Adair-Albany Mutual Aid Response District Adair RFPD Albany Fire District Alsea RFPD Blodgett-Summit RFPD Corvallis Fire Department Corvallis RFPD 9-20 Hoskins-Kings Valley RFPD Monroe RFPD Philomath Fire District Each of the fire protection service providers in Benton County was surveyed to determine areas of special concern with high potential for wildland/urban interface fires. Many of these identified areas of special concern are likely to be high priority areas for mitigation actions to reduce fire risks. Survey results from several Benton County fire agencies are summarized below in Table 9.5. Completion of these surveys for all fire agencies in Benton County is a high priority action item. Table 9.5 Areas of Special Concern for Wildland/Urban Interface Fires Monroe RFPD Geographic Area of Concern Shady Oak Drive residential area in forested area with little or no regard for fire suppression needs X X X XXX Orchard Tract Road residential area in forested area with little or no regard for fire suppression needs X X X XXX Hells Canyon Road residential area in forested area with little or no regard for fire suppression needs X X X XXX multiple rural addresses in service area residential areas in forested area with little or no regard for fire suppression needs X X X XXX Corvallis Geographic Area of Concern Crescent Valley / Vineyard Mountain Area of high value homes from 10 to 40 years old in forested area in the Corvallis RFPD X X X XXX Oak Creek West of Corvallis along Oak Creek for about 5 miles X X X XXXX Skyline West Northwest of Corvallis off Ponderosa Drive in forested area with areas of heavy underbrush. Many homes have brush adjacent to structure and combustible roofing. X X X XXX Limited Water SuppliesLimited Water SuppliesNon-Firesafe Construction PracticesSteep TopographyLimited Access/EgressDistance/Time from fire Dept Narrative of High Risk Situation Narrative of High Risk Situation High Vegetative Fuel Loads P oor vege t a ti on clearance around st r uctu r es High Vegetative Fuel Loads P oor vege t a ti on clearance around st r uc t u r es Non-Firesafe Construction PracticesSteep TopographyLimited Access/EgressDistance/Time from fire Dept 9-21 Table 9.5 (continued) Areas of Special Concern for Wildland/Urban Interface Fires Philomath Fire & Rescue Geographic Area of Concern Marys River Estates Subdivision High concentration of houses in interface area with no fire hydrants, narrow steep roads and driveways with only one access/egress road X X X XXXX Pioneer Village Subdivision High concentration of houses in interface area with no fire hydrants, narrow steep roads and driveways with only one access/egress road X X X XXXX Sunshine Village Subdivision Subdivision in interface area with fire hydrants that do not meet fire flow recommendations XX Hidden Valley Estates Subdivision High concentration of houses in interface area with no fire hydrants, narrow steep roads and driveways with only one access/egress road X X X XXXX Steep TopographyLimited Access/EgressDistance/Time from fire DeptLimited Water Supplies Narrative of High Risk Situation High Vegetative Fuel Loads X P oor vege t a ti on clearance around st r uc t u r es Non-Firesafe Construction Practices 9-22 The potential impacts of wildland/urban interface fires on Benton County are summarized below in Table 9.6. Table 9.7 Potential Impacts of Wildland/Urban Interface Fires On Benton County Inventory Probable Impacts Portion of Benton County affected Highest risk areas are residential areas bordering heavily vegetated wildland areas. These areas include many of the smaller communities in Benton County and portions of the larger communities (See Table 9.5 and maps above). Buildings Small wildland/urban interface fires could affect a few residential buildings. Larger fires could effect entire neighborhoods and extreme events (cf. Oakland Hills 1991 fire) could affect hundreds of buildings Streets within communities Minor road closures possible from fires; limited impact because of short detour routes within communities. Roads within and to/from Benton County Potential closures of major highways due to fires, especially roads in the westerm portions of Benton County. Electric power Potential for localized loss of electric power due to fires affecting power lines in or near Benton County Other Utilities Generally minor or no impacts on other utilities from fires, except for possible loss of telephone service due to fires affecting phone poles/lines. Casualties Potential for deaths and injuries in major wildland/urban interface fires, especially if evacuations are not completed expeditiously. 9.6 Mitigation Strategies This section outlines suggested strategies for reducing the level of risk to both property and life safety in wildland/urban interface development areas that may be at high risk from wildland/urban interface fires. The suggested mitigation strategy has four elements: 1) reduce the probability of fire ignitions, 2) reduce the probability that small fires will spread, 3) minimize property damage, and 4) minimize the life safety risk. Reduce the probability of fire ignitions Efforts to reduce the probability of fire ignitions should focus on manmade causes of ignition through a combination of fire prevention education, enforcement, and other actions. Fire prevention education actions could include efforts to heighten public awareness of fire dangers, especially during high danger time periods and better education about fire safe practices, such as careful disposal of smoking materials, and adhering to restrictions on burning of rubbish and debris. Fire prevention enforcement action could include strict enforcement of burning restrictions and vigorous investigation and prosecution of arson cases. An important physical action to reduce the probability of ignitions is to maintain or upgrade tree-trimming operations around power lines to 9-23 minimize fires starting by sparking from lines to vegetative fuels. Reduce the probability that small fires will spread. Possible mitigation actions to reduce the probability that small fires will spread include enhancement of water supply and fire suppression capabilities for high-risk areas, expansion of existing firebreaks, creation of new firebreaks and expanding defensible spaces around structures in wildland/urban interface areas. Geographical area specific pre-emergency planning by jurisdiction should also be conducted to help optimize fire response strategies. Minimize Property Damage The education and action items discussed above may help to reduce future property damages by reducing the number of fire ignitions and by reducing the probability that a small fire will spread. In addition, specific fire safe building practices should be implemented (if not yet implemented) or enforced vigorously (if not yet vigorously enforced). Fire safe building practices have two main elements: first, design of structures, and second, creation of defensible spaces around structures. The USFA (www.usfa.fema.gov) and other organizations have many sources of information about fire safe practices in the wildland/urban interface. For example, the National Fire Protection Association (NFPA) has an excellent ?Firewise? communities program with an excellent, highly informative website (www.firewise.org). The firewise website can also be reached from the main NFPA website (www.nfpa.org). The Firewise website has very informative publications and videos for local officials and homeowners to help understand, evaluate, and improve the fire safety of structures at risk from wildland/urban interface fires. Similar information is also available at the FireFree site by the Safeco Insurance Company: (www.safeco.com/safeco/about/giving/firefree.asp) The NFPA Firewise construction and firewise landscaping checklists are particularly recommended as concise summaries of the primary fire-safe designs and practices for homeowners at risk from wildland/urban interface fires. The NFPA?s Firewise Construction Checklist, makes the following main recommendations (among others): 1) site homes on as level terrain as possible, at least 30 feet back from cliffs or ridgelines, 2) build homes with fire-resistant roofing materials, such as Class-A asphalt shingles, slate or clay tiles, concrete or cement products, or metal. 3) build homes with fire-resistant exterior wall cladding, such as masonry or stucco, 9-24 4) consider the size and materials for windows; smaller panes hold up better than larger ones, double pane and tempered glass windows are more fire resistant than single pane windows; plastic skylights can melt and allow access for burning embers, 5) prevent sparks and embers from entering vents by covering vents with wire mesh no larger than 1/8", box eaves, and minimize places to trap embers on decks and other attached structures, and 6) keep roofs, eaves, and gutters free of flammable debris. The NFPA?s Firewise Landscaping Checklist includes the following main recommendations (among others), based on a four-zone planning concept around the house: 1) Zone 1 should be well irrigated area of closely mowed grass or non-flammable landscaping materials such as decorative stone, at least 30' in all directions around the home, 2) Zone 2 should be a further irrigated buffer zone with only a limited number of low-growing, fire-resistant plants, 3) Zone 3, further from the house, can include low growing plants and well- spaced, well-pruned trees, keeping the total vegetative fuel load as low as possible, and 4) Zone 4 is the natural area around the above three landscaped zones. This area should be thinned selectively, with removal of highly flammable vegetation and removal of ladder fuels that can spread a grass fire upwards into treetops. Minimize Life Safety Risk The mitigation actions above may help to minimize life safety risk by helping to reduce the number of ignitions, by reducing the probability that small fires will spread, and by encouraging more fire-safe practices of building construction and fire-safe landscaping. These practices are meritorious for reducing the fire hazards to structures. However, they may also give homeowners a false sense of life safety security. A false sense of security may encourage people to stay in homes at risk during wildfires, rather than evacuating immediately at the first fire warning. The most important action to minimize life safety risk during wildland/urban interface fires is immediate evacuation. However, evacuations must be directed by the responsible fire agencies to ensure both egress for residents and access for fire apparatus and personnel. Uncontrolled evacuations can sometimes block access and thus potentially increase fire spread. Thus, reducing life safety risk requires public education and emergency planning to encourage and expedite warnings and evacuations (voluntary or mandatory). 9-25 9-26 Life safety risk during wildland/urban interface fires is exacerbated by limited evacuation routes. Improving evacuation roads (widening, straightening) and, most importantly, providing as many alternate evacuation routes as possible can significantly reduce evacuation times and lower the probability that residents seeking to evacuate may be trapped by fire-blocked routes. The following table contains wildland/urban interface fire mitigation action items from the master Action Item table in Chapter 4. Table 9.8 Wildland/Urban Interface Fire Mitigation Action Items Mitigation Plan Goals Addressed Hazard Action Item Coordinating Organizations Timeline Life Safety Critical Facilities and Emergency Services Protect Property Disaster Resilient Economy Public Education, Outreach, Partnerships Wildland/Urban Interface Fire Mitigation Action Items Short-Term #1 Identify specific parts of Benton County at high risk for urban/wildland urban interface fires because of fuel loading, topography and prevailing construction practices Benton County GIS and Community Development, Benton County Fire Defense Board, fire agencies 1-2 Years X X X X X Short-Term #2 Identify evacuation routes and procedures for high risk areas and educate the public Benton County Fire Defense Board, fire agencies, law enforcement, County Roads, public works Ongoing X X X X Short-Term #3 Develop Community Wildland Fire Protection Plans Benton County Community Development, cities, fire agencies, ODF 1-2 Years X X X X X Short-Term #4 Collect statistics on non-ODF vegetation fires from local fire agencies Benton County Fire Defense Board, GIS 1 year X X X X Short-Term #5 Complete surveys of areas of special concern for Wildland/urban interface firs from remaining l fire agencies in Benton County along the lines of Table 9.5 above Local Fire Departments, Benton County Emergency Services 1 year X X X X Long-Term #1 Encourage fire-safe construction practices for existing and new construction in high risk areas Benton County Community Development, city building departments, fire agencies Ongoing X X X X X 9-27 This Page Left Blank 9-28 10.0 EARTHQUAKES Historically, awareness of seismic risk in Oregon has generally been low, among both the public at large and public officials. This low level of awareness reflected the low level of seismic activity in Oregon, at least in recent historical time. However, over the past several years, awareness of seismic risk in Oregon has significantly increased. Factors in this increased awareness include the 1993 Scotts Mills earthquake in Clackamas County, widespread publicity about possible large magnitude earthquakes on the Cascadia Subduction Zone, and recent changes in Seismic Zonation in the Oregon Building Code, which increased seismic design levels for new construction in western Oregon. Before reviewing the levels of seismic hazard and seismic risk in Benton County, we first present a brief earthquake ?primer? that reviews some basic earthquake concepts and terms. 10.1 Earthquake Primer In the popular press, earthquakes are most often described by their Richter Magnitude (M). Richter Magnitude is a measure of the total energy released by an earthquake. In addition to Richter magnitude, there are several other measures of earthquake magnitude used by seismologists, but such technical details are beyond the scope of this discussion. The Scotts Mills (Oregon) earthquake was M = 5.6, while the Northridge (California) earthquake was about M = 6.7. Great earthquakes, for example, on the San Andreas Fault or on the Cascadia Subduction Zone, may have magnitudes of 8 or greater. It is important to recognize that the Richter scale is not linear, but rather logarithmic. A M8 earthquake is not twice as powerful as a M4, but rather thousands of times more powerful. A M7 earthquake releases about 30 times more energy than a M6, while a M8 releases about 30 times more energy than a M7 and so on. Thus, great M8 earthquakes may release thousands of times as much energy as do moderate earthquakes in the M5 or M6 range. The public often assumes that the larger the magnitude of an earthquake the ?worse? the earthquake. Thus, the ?big one? is the M8 earthquake and smaller earthquakes (M6 or M7) are not the ?big one?. However, this is true only in very general terms. Larger magnitude earthquakes affect larger geographic areas, with much more widespread damage than smaller magnitude earthquakes. However, for a given site, the magnitude of an earthquake is NOT a good measure of the severity of the earthquake at that site. Rather, the intensity of ground shaking at the site depends on the magnitude of the earthquake and on the distance from the site to the earthquake. An earthquake is located by its epicenter - the location on the earth?s surface directly above the point of origin of the earthquake. Earthquake ground shaking diminishes (attenuates) with distance from the epicenter. Thus, any given earthquake will produce the strongest ground motions near the earthquake with the intensity of ground motions diminishing 10-1 with increasing distance from the epicenter. Thus, for a given site, a smaller earthquake (such as a M6.5), which is very close to the site, could cause greater damage than a much larger earthquake (such as a M8) that is quite far away from the particular site. However, earthquakes at or below M5 are not likely to cause significant damage, even locally very near the epicenter. Earthquakes between about M5 and M6 are likely to cause some damage very near the epicenter, with the extent of damage typically being relatively minor (e.g., the 1993 Scotts Mills earthquake). Earthquakes of about M6.5 or greater can cause major damage (e.g., the Northridge earthquake), with damage usually concentrated fairly near the epicenter. Larger earthquakes of M7+ cause damage over increasingly wider geographic areas with the potential for very high levels of damage near the epicenter. Great earthquakes with M8+ can cause major damage over wide geographic areas. For example, a M8+ on the Cascadia Subduction Zone could affect the entire Pacific Northwest from British Benton, through Washington and Oregon, and as far south as Northern California. The intensity of ground shaking varies not only as a function of M and distance but also depends on soil types. Soft soils may amplify ground motions and increase the level of damage. Thus, for any given earthquake there will be contours of varying intensity of ground shaking. The intensity will generally decrease with distance from the earthquake, but often in an irregular pattern, reflecting soil conditions (amplification) and possible directionality in the dispersion of earthquake energy. There are many measures of the severity or intensity of earthquake ground motions. A very old, but commonly used, scale is the Modified Mercalli Intensity scale (MMI), which is a descriptive, qualitative scale that relates severity of ground motions to types of damage experienced. MMIs range from I to XII. More useful, modern intensity scales use terms that can be physically measured with seismometers, such as the acceleration, velocity, or displacement (movement) of the ground. The most common physical measure, and the one used in this Mitigation Plan, is Peak Ground Acceleration or PGA. PGA is a measure of the intensity of shaking, relative to the acceleration of gravity (g). For example, 1.0 g PGA in an earthquake (an extremely strong ground motion) means that objects accelerate sideways at the same rate as if they had been dropped from the ceiling. 10% g PGA means that the ground acceleration is 10% that of gravity and so on. Damage levels experienced in an earthquake vary with the intensity of ground shaking and with the seismic capacity of structures. Ground motions of only 1 or 2% g are widely felt by people; hanging plants and lamps swing strongly, but damage levels, if any, are usually very low. Ground motions below about 10% g usually cause only slight damage. Ground motions between about 10% g and 30% g may cause minor to moderate damage in well-designed buildings, with higher levels of damage in poorly designed buildings. At this level of ground shaking, only unusually poor buildings would 10-2 be subject to potential collapse. Ground motions above about 30% g may cause significant damage in well-designed buildings and very high levels of damage (including collapse) in poorly designed buildings. Ground motions above about 50% g may cause high levels of damage in many buildings, even those designed to resist seismic forces. 10.2 Seismic Hazards for Benton County Earthquakes in Western Oregon, and throughout the world, occur predominantly because of plate tectonics - the relative movement of plates of oceanic and continental rocks that make up the rocky surface of the earth. Earthquakes can also occur because of volcanic activity and due to other geologic processes. The Cascadia Subduction Zone is a geologically complex area off the Pacific Northwest coast from Northern California to British Benton. In simple terms, several pieces of oceanic crust (the Juan de Fuca Plate, Gorda Plate and other smaller pieces) are being subducted (pushed under) the crust of North America. This subduction process is responsible for most of the earthquakes in the Pacific Northwest as well as for creating the volcanoes in the Cascades. Figure 10.1 shows the geologic (plate-tectonic) setting for Oregon. There are three source regions for earthquakes that can affect Benton County: 1) ?interface? or ?subduction zone? earthquakes on the boundary between the subducting oceanic plates and the North American plate, 2) ?intraslab? or ?intraplate? earthquakes within the subducting oceanic plates, which are also known as ?Benioff Zone? or deep zone earthquakes, and 3) ?crustal? earthquakes within the North American Plate. The geographic and geometric relationships of these earthquake source zones are shown in Figure 10.2 The ?interface? earthquakes on the Cascadia Subduction Zone may have magnitudes of 8 or greater, with probable recurrence intervals of 500 to 800 years. The last major earthquake in this source region probably occurred in the year 1700, based on current interpretations of Japanese tsunami records. Such earthquakes are the great Cascadia Subduction Zone earthquake events that have received attention in the popular press. These earthquakes typically occur about 20 to 60 kilometers (12 to 40 miles) offshore from the Pacific Ocean coastline. Ground shaking from such earthquakes would be very strong near the coast and moderately strong ground shaking would be felt throughout Benton County, with the level of shaking decreasing somewhat towards eastern Benton County. 10-3 10-4 Figure 10.2 Earthquake Source Zones 10-5 10-6 The ?intraslab? earthquakes, which are also called ?intraplate? or ?Benioff Zone? earthquakes, occur within the subducting oceanic plate. These earthquakes may have magnitudes up to about 7.5, with probable recurrence intervals of about 500 to 1000 years (recurrence intervals are poorly determined by current geologic data). These earthquakes occur quite deep in the earth, about 30 or 40 kilometers (18 to 25 miles) below the surface with epicenters that would likely range from near the Pacific Ocean coast to about 50 kilometers (30 miles) inland. Thus, epicenters from these types of earthquakes could be located in Lincoln County or western Benton County. Ground shaking from such earthquakes would be very strong near the epicenter and moderately strong ground shaking would be felt throughout all of Benton County, with the level of shaking decreasing towards eastern Benton County. ?Crustal? earthquakes within the North American plate are possible on faults mapped as active or potentially active as well as on unmapped (unknown) faults. The only mapped active fault in Benton County is the Corvallis Fault, which runs in a SW to NE direction through the center of the county. Historically observed crustal earthquakes in Oregon from 1841 to 2002 are shown in Figure 10-3 (DOGAMI, Map of Selected Earthquakes for Oregon, 1841 through 2002, Open-File Report 03-02, 2003). During this time period, only six small earthquakes have occurred in Benton County as shown on Figure 10.3. Larger earthquakes in nearby counties are also shown. However, based on the historical seismicity in Western Oregon and on analogies to other geologically similar areas, small to moderate earthquakes up to M5 or M5.5 are possible almost anyplace in Western Oregon, including almost anyplace in Benton County. Such earthquakes would be mostly much smaller than the Scotts Mills earthquake up to about the magnitude of that 1993 earthquake. The possibility of larger crustal earthquakes in the M6+ range cannot be ruled out. However, the probability of such events is likely to be very low. Because the probability of large crustal earthquakes (M6 or greater) affecting Benton County is low and because any damage in smaller crustal earthquakes is likely to be minor and very localized, crustal earthquakes are not considered significant for hazard mitigation planning purposes. Therefore, our analysis focuses on the larger, much more damaging earthquakes arising from the Cascadia Subduction Zone. Figure 10-3 Earthquake Epicenters from 1841 to 2002 10-7 10-8 This page left blank 10-9 The characteristics of the subduction zone earthquakes affecting Benton County are summarized in Table 10.4 below. The maximum magnitudes are estimated from the length and width of the mapped fault plane or from similar earthquakes elsewhere in the Pacific Northwest (for the intraslab earthquakes). Recurrence intervals are based on current best estimates. Table 10.4 Seismic Sources Affecting Benton County Fault Maximum Magnitude Probable Recurrence Interval (years) Cascadia Subduction Zone (interface earthquake) 8.5 500 to 800 Cascadia Subduction Zone (intraslab earthquake) 7.5 500 to 1000 In addition to these large earthquakes, the Cascadia Subduction Zone also experiences smaller earthquakes such as the M6.8 Nisqually earthquake near Olympia Washington that occurred on February 28, 2001. The Nisqually earthquake was an intraslab earthquake that occurred at a depth of 52 kilometers (about 30 miles). Other relatively recent similar Cascadia Subduction Zone earthquakes include the M7.1 Olympia earthquake in 1949 and the M6.5 Seattle- Tacoma earthquake in 1965. These earthquakes killed 15 people and resulted in over $200 million in damages (1984 dollars, www.dnr.wa.gov). Similar earthquakes are possible in Western Oregon, including Benton County. The following figure shows a generalized geologic map of Benton County and includes the Corvallis Fault and other mapped faults. The mapped faults within or near Benton County are relatively small and not very active. Thus, seismic hazard for Benton County arises predominantly from major earthquakes on the Cascadia Subduction Zone. Smaller, crustal earthquakes in or near Benton County could be locally damaging, but would not be expected to product widespread or major damage. Figure 5 Geologic Map of Benton County1 1 Preliminary Earthquake Hazard and Risk Assessment and Water-Induced Landslide Hazard in Benton County, Oregon. Zehnming Wang, Gregory Graham, and Ian Madin, DOGAMI Open File Report O-01-05, 2001. 10.3 Other Aspects of Seismic Hazards in Benton County Most of the damage in earthquakes occurs directly because of ground shaking which affects buildings and infrastructure. However, there are several other aspects of earthquakes that can result in very high levels of damage in localized sites: liquefaction, landslides, dam failures and tsunamis. 10.3.1 Soil Effects 10-10 Liquefaction is a process where loose, wet sediments lose strength during an earthquake and behave similarly to a liquid. Once a soil liquefies, it will tend to settle and/or spread laterally. With even very slight slopes, liquefied soils tend to 10-11 move sideways downhill (lateral spreading). Settling or lateral spreading can cause major damage to buildings and to buried infrastructure such as pipes and cables. In general, areas of high liquefaction potential largely follow river and stream drainage channels, marshy areas and areas near lakes. In addition, similar soil conditions may occur in areas where lakes or streams existed in the past but have now been filled in by natural or human-caused processes. In earthquakes, liquefaction, settling or lateral spreading does not occur in all such areas or in all earthquakes. However, in larger earthquakes with strong ground shaking and long duration shaking, liquefaction is likely in many of these high liquefaction potential areas. Settlements of a few inches or more and lateral spreads of a few inches to several feet are possible. Even a few inches of settlement or lateral spreading is likely to cause significant to major damage to affected buildings or infrastructure. For Benton County, DOGAMI has prepared countywide maps of areas known or likely to be affected by these soils effect (Preliminary Earthquake Hazard and Risk Assessment and Water-Induced Landslide Hazard in Benton County Oregon, Open File Report O-01-05, 2001). This DOGAMI publication includes maps of areas subject to liquefaction, amplification of earthquake ground motions, and earthquake induced landslides. These maps are based on available data and should not be over interpreted to represent exact locations of soils subject to liquefaction. Not all areas within given bins of liquefaction potential may be as classified: some areas may have higher potential and some areas may have lower potential. Detailed site-specific geotechnical studies are necessary to determine the level of liquefaction, settlement or lateral spread hazard at any specific location. The DOGAMI maps (Open File Report O-01-05) showing areas with moderate or high liquefaction potential are included on the following pages. ? Low resolution map for all of Benton County, and ? More detailed maps for o North Corvallis, Adair, North Albany o Corvallis, Philomath o Summit, Blodgett, Wren o Bellfountain, Alpine, Monroe o Alsea. As shown on these maps, areas with high liquefaction potential (as well as potential for lateral spreading or settlement) are generally located near the Willamette and along other river valleys in Benton County. 10-12 This page left blank DOGAMI Liquefaction Potential Map Benton County 10-13 DOGAMI Liquefaction Potential Map North Corvallis, Adair, North Albany 10-14 DOGAMI Liquefaction Potential Map Corvallis, Philomath 10-15 DOGAMI Liquefaction Potential Map Summit, Blodgett, Wren 10-16 DOGAMI Liquefaction Potential Map Bellfountain, Alpine, Monroe 10-17 DOGAMI Liquefaction Potential Map 10-18 Alsea 10.3.2 Landslides Earthquakes can also induce landslides, especially if an earthquake occurs during the rainy season and soils are saturated with water. The areas prone to earthquake-induced landslides are largely the same as those areas prone to landslides in general. As with all landslides, areas of steep slopes with loose rock or soils are most prone to earthquake- induced landslides. Areas with steep slopes and loose rock or soils that are prone to water-induced landslides or debris flows are also subject to earthquake-induced landslides. For reference, see the landslide and debris flow hazard maps in Chapter 8 Landslides. 10.3.3 Dam Failures Earthquakes can also cause dam failures in several ways. The most common mode of earthquake-induced dam failure is slumping or settlement of earthfill dams where the fill has not been properly compacted. If the slumping occurs when the dam is full, then overtopping of the dam, with rapid erosion leading to dam failure is possible. Dam failure is also possible if strong ground motions heavily damage concrete dams. In a few cases, earthquake-induced landslides into reservoirs have caused dam failures. Earthquake-induced dam failures are addressed in more detail in Chapter 12, which covers dam failures that could affect Benton County. 10.3.4 Tsunamis and Seiches Tsunamis, which are often incorrectly referred to as ?tidal waves,? result from earthquakes which cause a sudden rise or fall of part of the ocean floor. Such movements may produce tsunami waves, which have nothing to do with the ordinary ocean tides. In the open ocean, far from land, in deep water, tsunami waves may be only a few inches high and thus be virtually undetectable, except by special monitoring instruments. These waves travel across the ocean at speeds of several hundred miles per hour. When such waves reach shallow water near the coastline, they slow down and can gain great heights. Tsunamis affecting the Oregon coast can be produced from very distant earthquakes off the coast of Alaska or elsewhere in the Pacific Ocean. For such tsunamis, the warning time for the Oregon coast would be at least several hours. However, interface earthquakes on the Cascadia Subduction Zone can also produce tsunamis. For such earthquakes the warning times would be very short, only a few minutes. Because of this extremely short warning time, emergency planning and public education are essential before such an event occurs. For Benton County, not being on the coast, there are no impacts from tsunamis. Another earthquake related phenomenon is ?seiches? which are waves from sloshing of 10-19 inland bodies of waters such as lakes, reservoirs, or rivers. In some cases, seiches have caused damages to shorefront structures and to dams. However, for the Benton County the potential for seiches of sufficient magnitude to cause significant damage to upstream dams appears low. 10.4 Risk Assessment for Scenario Earthquakes For regional planning purposes, FEMA?s HAZUS-MH (Hazards U.S. Multi-Hazard) software can be used to make estimates of countywide damages in Benton County from two scenario earthquakes. HAZUS is an extensively peer-reviewed nationally applicable loss estimation methodology that draws heavily on census and other nationally available data on buildings and infrastructure. The two scenario earthquakes considered include: a) a M8.5 Cascadia Subduction Zone Interface Earthquake and b) a M7.5 Cascadia Subduction Zone Intraplate (Benioff Zone) Earthquake. The earthquake loss estimates shown below were calculated in 2001 for Phase Two of the Regional All Hazard Mitigation Master Plan for Benton, Lane, and Linn Counties, using a methodology very similar to HAZUS. For each of these scenario earthquakes, building damage estimates for Benton County are approximately $400 million. Injuries were estimated to be about 600 for daytime earthquakes and about 160 to 170 for nighttime earthquakes. Deaths were estimated to be about 12 for daytime earthquakes and about 1 for nighttime earthquakes. Casualties are much lower for nighttime earthquakes, because most of the population is in mostly wood-frame residential buildings, which typically have lower casualty rates than many other types of structures. Summary results are shown below in Tables 10-6 and 10-7. 10-20 10.4.1 M8.5 Cascadia Subduction Zone Interface Earthquake The estimated impacts of this earthquake on the building stock in Benton County are summarized below in Table 10.6. Table 10.6 M8.5 Cascadia Subduction Zone Interface Earthquake Loss Estimate Benton County Building Damage $420,000,000 Percent Damage1 11.40% Daytime Deaths 12 Daytime Injuries 646 Nighttime Deaths 1 Nighttime Injuries 170 Heavily Damaged Residential Buildings2 1,711 Estimated number of people needing emergency shelter3 3,422 1 Percent damage is relative to building replacement value. 2 Heavily damaged buildings are those in the extensive or complete damage states. 3 Of the total displaced people, perhaps 1/3 will need public emergency shelter, with the rest finding shelter with relatives, friends, or in commercial lodgings. The direct loss estimates shown above are for the building stock only. Including the direct damages to contents, infrastructure and direct economic impacts from loss of function, the total direct economic impacts of these scenario earthquakes may be about double the estimates shown above For such an earthquake, a substantial fraction of the larger buildings in the area will be damaged, including many essential service facilities, such as hospitals, fire and police stations, schools, and emergency shelters. For example, approximately one quarter of the hospital beds in affected counties may not be available, due to structural and/or non- structural damage to hospitals. Utility systems will be significantly damaged, including damaged buildings and damage to utility infrastructure, including water and wastewater treatment plants and equipment at high voltage substations (especially 230 kV or higher which are more vulnerable than lower voltage substations). Buried pipe systems will suffer extensive damage with approximately one break per mile in soft soil areas. There would be much lower rate of 10-21 pipe breaks in other areas. Restoration of utility services will require substantial mutual aid from utilities outside of the affected area. Expected outages of utility and transportation systems may include approximately: Water: 10 days with no water to about 25% of customers in urban areas, 20 days to restore water service to 99% of customers, Wastewater loss of function at one or two treatment plants, Natural gas: similar to water service, in areas served by natural gas distribution systems, Electric power: widespread outages for 8 to 24 hours, local outages in rural areas up to 72 hours, Phone systems: system overload for about 72 hours, most customers have normal service after 72 hours, similar situation with cellular customers, Highways: about 10 days to make emergency repairs, about 3 to 5% of bridges in complete damage state. 10.4.2 M7.5 Cascadia Subduction Zone Intraplate Earthquake The estimated impacts of this earthquake on the building stock in Benton County are summarized below in Table 10.7. Table 10.7 M7.5 Cascadia Subduction Zone Intraplate Earthquake Loss Estimate Benton County Building Damage $398,000,000 Percent Damage1 10.80% Daytime Deaths 11 Daytime Injuries 602 Nighttime Deaths 1 Nighttime Injuries 157 Heavily Damaged Residential Buildings2 1,853 Estimated number of people needing emergency shelter3 3,706 1 Percent damage is relative to building replacement value. 2 Heavily damaged buildings are those in the extensive or complete damage states. 10-22 3 Of the total displaced people, perhaps 1/3 will need public emergency shelter, with the rest finding shelter with relatives, friends, or in commercial lodgings. The direct loss estimates shown above are for the building stock only. Including the direct damages to contents, infrastructure and direct economic impacts from loss of function, the total direct economic impacts of these scenario earthquakes may be about double the estimates shown above In addition to building damages, utility systems (electric power, water, wastewater, natural gas) and transportation systems (bridges, pipelines) are also likely to experience significant damage. These types of damage and economic impacts are likely to be similar to those summarized above for the M8.5 Interface earthquake. The potential impacts of major earthquakes on Benton County are summarized below in Table 10.8. Table 10.8 Potential Impacts of Major Earthquakes on Benton County Inventory Probable Impacts Portion of Benton County affected Entire County and surrounding region, highest levels of ground shaking and damage percentages likely in western Benton County Buildings Many buildings will have no damage or light to moderate damage, with heavy damage concentrated in vulnerable buildings (wood frame buildings with cripple walls, unreinforced masonry, etc.). Total building damage estimated to be about $400 million. Streets within Benton County Minor road damage possible in areas of soft soils. Many bridges may have significant damage, 3% to 5% may be in complete damage state. Roads to/from Benton County Minor road damage possible in areas of soft soils. Many bridges may have significant damage, 3% to 5% may be in complete damage state. Electric power Widespread outages for about 8 to 24 hours. Rural areas may have outages up to 72 hours. Water utilities About 10 days with no water to about 25% of customers in urban areas, about 20 days to restore water service to 99% of customers. Other Utilities Loss of function to one or two wastewater treatment plants. Natural gas system damages and outages similar to water systems. Phone systems (land and cellular) will have system overload for about 72 hours, then most customers will have normal service. Emergency Shelter Needs Approximately 3,000 to 4,000 people may need emergency shelter. Casualties About 12 deaths for daytime earthquake or about 1 death for nighttime earthquake. Daytime injuries about 600; nighttime injuries about 160 to 170. The above summary of potential impacts is for major earthquakes on the Cascadia 10-23 Subduction Zone, as shown above in Tables 10.6 and 10.7. Smaller earthquakes would have substantially smaller impacts on Benton County than shown above. In addition, there is a low probability that a major earthquake could result in substantial damage or failure of the major dams upstream of Benton County (cf. Chapter 12 Dams). 10.5 Earthquake Risk Assessment: Technical Guidance For planning purposes, it is sometimes useful to consider three levels of earthquake risk assessment. A Level One Risk Assessment means that nationally available data are used. For example, FEMA?s HAZUS loss estimation software uses national data and HAZUS risk assessments for a community are Level One. The risk assessments presented in the previous section were Level One Assessments using HAZUS. A Level Two Risk Assessment is a more refined evaluation using local data such as soil maps, assessor?s records, local building code history and so on to more accurately reflect local conditions than when using only national data. Level Two Assessments are generally more accurate than Level One Assessments, but still rely on generalized, typical data, rather than building specific data. A Level Three Risk Assessment is building- or facility-specific, using detailed data for each facility. A Level Three Risk Assessment cannot be done for an entire community, but rather is typically done for a single building or a few buildings or other facilities that may be particularly vulnerable or for which mitigation of seismic hazards is a high priority. 10.5.1 Level Two Risk Assessment The Level One earthquake loss estimates presented above are based on census-tract level data. For a given community, a more accurate loss estimate could be obtained by incorporating Level Two local data into the loss calculations. Such data could include: 1) better inventory data, 2) spatial distribution of inventory within census tracts, 3) overlay of soils information with inventory to identify areas subject to amplification, liquefaction, settling and displacements, and 4) refinement of building fragility curves to reflect local inventory. Such Level Two loss estimates would be more accurate than the Level One assessments presented above. However, the Level One estimates probably provide accurate enough estimates of the approximate magnitude of losses for emergency planning purposes. 10-24 Furthermore, conducting a Level Two loss estimate would require very intensive data collection and processing efforts, without providing enough detail for specific mitigation projects. Therefore, Level Two risk assessments may not be as useful for Benton County as the Level Three Assessments suggested below. 10.5.2 Level Three Risk Assessment The potential damages and losses from earthquakes affecting Benton County are very high. However, the probability of such earthquakes is relatively low and many types of buildings, such as wood frame homes, are generally expected to perform reasonably well in earthquakes. Therefore, widespread mitigation of seismic hazards is probably not called for in the case of most ordinary or typical buildings. That is, seismic mitigation actions are probably necessary only for a small percentage of the total building stock in Benton County. Furthermore, buildings constructed since the early 1990s generally meet current seismic design requirements and will generally perform fairly well in future earthquakes. Similarly, new buildings will be built in accordance with current Seismic Zone 3 requirements and thus the seismic capacity of the building stock in Benton County will gradually improve over time as the existing stock is gradually replaced and/or upgraded. However, for some types of buildings that are more vulnerable or more important than typical buildings, seismic retrofit may be highly desirable. Prime candidates for possible seismic retrofits include: ? any buildings that are substantially more vulnerable than typical buildings (e.g., unreinforced masonry buildings), ? buildings on soft soil sites, and ? essential service facilities such as major medical facilities, police and fire stations, schools, and emergency shelters. Specific buildings may be substantially more vulnerable than typical buildings because of their structural system. Examples of vulnerable building types include: unreinforced masonry, precast concrete frame, concrete or steel frame with unreinforced masonry infill walls, concrete moment resisting frame, and precast concrete tilt up walls. Buildings may also be substantially more vulnerable than typical buildings because of their design characteristics. Examples include buildings with soft first stories (taller than other stories and/or with large expanses of windows without shear walls) and buildings with major configurational irregularities, as well as wood frame buildings with cripple wall foundations or with sill plates not bolted to the foundation. Thus, we suggest that Level Three risk assessments focus primarily on such buildings, especially for essential service facilities. A Level Three assessment provides a building-specific evaluation, more accurate than generic assessments based on typical buildings. Ideally, a Level Three assessment would include a site-specific seismic hazard analysis, taking into account soil conditions, and a 10-25 building-specific evaluation of the seismic vulnerability of each building under evaluation. In addition to buildings, there are other critical facilities that may be vulnerable to seismic damage, including utility and transportation system infrastructure. Minimizing earthquake damage to such facilities is particularly important to a community because loss of function of critical utility or transportation system infrastructure may have a very large economic impact on the community. Facilities that should have a high priority for Level Three Risk Assessments include: electric power substations (especially high voltage substations), water and waste-water treatment plants, water reservoirs, bulk fuel storage tanks and hazmat storage tanks, dams and bridges. For utilities in general, non-structural mitigation measures are often very cost-effective and should have a high priority. For buildings, utilities and other important facilities, the seven-step Mitigation Planning methodology outlined in Chapter 1 is appropriate. For prioritizing between mitigation projects, the principles of benefit-cost analysis apply to mitigation projects for all hazards, including seismic hazard mitigation. FEMA has software available to conduct such analyses of prospective earthquake hazard mitigation projects. See also the example seismic mitigation project in the Appendix to this Chapter. 10.6 Other Earthquake Risk Comments for Benton County A ?windshield? survey means a quick, preliminary seismic risk evaluation of a building or other facility, based on readily observable external attributes. A windshield survey may literally be done from a vehicle, but more commonly includes a quick walk around inspection. Conclusions drawn from such preliminary evaluations must be interpreted carefully as giving only a general indication of the probable level of seismic risk posed by the building or facility. The following comments are based on a very limited windshield type survey of Benton County?s population centers. Overall, a majority of the building inventory in Benton County is residential, with most residential structures being wood frame buildings. In general, wood frame buildings perform well in earthquakes, with a few notable exceptions. Wood frame buildings with the following characteristics are generally substantially vulnerable to major seismic damage: 1) sill plates not bolted to foundation, 2) cripple wall perimeter systems, and 3) buildings on steep slopes, partially supported on ?stilts.? Cripple wall perimeter systems are short wooden walls that raise the first floor elevation above grade by typically about 2 to 4 feet. Unbolted sill plates and cripple wall construction are common in pre-WW2 construction. Visual inspection and the general vintage of building stock in Benton County suggest that there are likely significant numbers of buildings in Benton County with cripple wall foundations or with unbolted sill plates. About 10% of the residential building stock in Benton County pre-dates 1940 (cf. Table 10-26 2.6). Unreinforced masonry buildings are also subject to major damage in earthquakes. Benton County has at least several dozen masonry buildings (most commercial or industrial in the older central business districts of most communities) which may be unreinforced or reinforced masonry. Some of these buildings may be highly vulnerable to earthquake damage and thus should have a high priority for detailed evaluation, especially those buildings with high occupancies or important functions. A detailed inventory of wood frame buildings with the above noted seismic deficiencies and inventory of unreinforced masonry buildings would be useful to further quantify the level of risk posed by such structures in Benton County. 10.7 Earthquake Hazard Mitigation Projects: General Examples There are a wide variety of possible hazard mitigation projects for earthquakes. The most common projects include: structural retrofit of buildings, non-structural bracing and anchoring of equipment and contents, and strengthening of bridges and other infrastructure components. The seismic hazard (frequency and severity of earthquakes) is moderate in the Benton County. However, the risk (potential for damages and casualties) may be fairly high because some buildings and infrastructure may be highly vulnerable to earthquake damages. The risk assessment methodology outlined above for earthquakes provides the basis for identifying the high-risk facilities that then become the primary targets for mitigation. Structural retrofit of buildings should not focus on typical buildings, but rather on buildings that are most vulnerable to seismic damage. Priorities should include buildings on soft soil sites subject to amplification of ground motion and/or liquefaction and especially on critical service facilities such as hospitals, fire and police stations, emergency shelters, and schools. Non-structural bracing of equipment and contents is often the most cost-effective type of seismic mitigation project. Inexpensive bracing and anchoring may protect very expensive equipment and/or equipment whose function is critical such as medical diagnostic equipment in hospitals, computers, communication equipment for police and fire services and so on. For utilities, bracing of control equipment, pumps, generators, battery racks and other critical components can be powerfully effective in reducing the impact of earthquakes on system performance. Such measures should almost always be undertaken before considering large-scale structural mitigation projects. The strategy for strengthening bridges and other infrastructure follows the same principles as discussed above for buildings. The targets for mitigation should not be typical infrastructure but rather specific infrastructure elements that have been identified as being 10-27 unusually vulnerable and/or are critical links in the lifeline system. For example, vulnerable overpasses on major highways would have a much higher priority than overpasses on lightly traveled rural routes. The following table contains earthquake mitigation action items from the master Action Item table in Chapter 4. 10-28 10-29 This page left blank Table 10.9 Earthquake Mitigation Action Items Mitigation Plan Goals Addressed Hazard Action Item Coordinating Organizations Timeline Life Safety Critical Facilities and Emergency Services Protect Property Disaster Resilient Economy Public Education, Outreach, Partnerships Earthquake Mitigation Action Items Short-Term #1 Complete inventory of public and commercial buildings that may be particularly vulnerable to earthquake damage Benton County GIS, Community Development, cities, special districts 1-2 Years X X X X X Short-Term #2 Complete inventory of wood-frame residential buildings that may be particularly vulnerable to earthquake damage, including pre-1940s homes and homes with cripple wall foundations. Benton County GIS, Community Development, cities, special districts 1-2 Years X X X X X Short-Term #3 Disseminate FEMA pamphlets to educate homeowners about structural and non-structural retrofitting of vulnerable homes and encourage retrofit Benton County Community Development, Emergency Management, Hazard Mitigation Steering Committee Ongoing X X X X Short-Term #4 Complete seismic vulnerability analysis of important public facilities with significant seismic vulnerabilities County, cities, special districts 1-2 Years X X X X X Long-Term #1 Obtain funding and retrofit important public facilities with significant seismic vulnerabilities County, cities, special districts 10 years X X X X X Long-Term #2 Retrofit bridges that are not seismically adequate for lifeline transportation routes ODOT, County, cities, roads X X X X X 10-30 10-31 This page left blank APPENDIX Example Mitigation Project Seismic Retrofit of Monroe High School A10.1 Monroe High School, Monroe, Benton County A10.1.1 Overview of As-Is Condition and Suggested Seismic Retrofit The Monroe High School is a complex of five buildings located on the east side of Highway 99E in Monroe (Benton County). The original building (circa 1915) is an unreinforced masonry building, L-shaped in plan, with brick and hollow clay tile walls. The roof structure is straight sheathing timbers, nailed to a timber truss. Most of the building is a single story structure, with the exception of a second story at the main entrance on the west exposure. The total floor area of the original building is about 17,200 square feet. The other four buildings are more recent additions. A music room (circa 1960s), is a light reinforced concrete frame structure with (apparently) unreinforced concrete masonry unit infill walls. The south addition (circa 1972) is a one-story brick structure that may be unreinforced masonry. Two newer buildings, including a gymnasium, are located northeast of the main building. The survey inspection of the campus (Section 5.3 of the Phase Two Technical Appendix) included the original building and the music room, but not the three newest buildings. The sections below, including the benefit-cost analysis, consider only the original building. A survey inspection of the original building was conducted in September 1999; see Section 5.3 of the Phase Two Technical Appendix for details of the engineering observations and analyses for this building. Among the important observations are: 1) the roof is straight wood sheathing over timber trusses. Straight wood sheathing has much less lateral strength than does plywood sheathing. 2) the roof trusses are connected to the exterior walls in a manner that appears to preclude a good shear transfer from the roof sheathing to the wall system. 3) the floors of the classrooms are presumed to be straight sheathing atop wood joists and beams. The connection system of the joists to the interior and edge walls was not confirmed, but is assumed (for purposes of this report) to not be positively anchored into the walls. 4) Recent remodeling of the attic used gypsum board for walls and plywood for the floors. However, these upgrades do not serve as structural systems, and do not improve the seismic performance, due to inadequate nailing and lack of continuity of the plywood floor to the edge wall systems. 10-32 Based on the preliminary evaluations described in the Phase Two Technical Appendix, the following preliminary suggestions for structural retrofit are made: 1) install plywood sheathing atop the existing straight sheathing on the roof, 2) block the edges of the roof truss system in a manner to allow good shear transfer from the roof diaphragm to the exterior brick piers, 3) select a suitable number of locations to upgrade the exterior brick piers to increase lateral load wall capacity. This could be done with shotcrete walls or steel diagonal braces, although the form of the retrofit should respect the historic nature of the building, 4) install drag beams (timber or steel) to transfer the roof load to the walls, 5) brace the interior CMU walls in the attics over entrance ways, to reduce falling hazards where there are regularly many people, and 6) if necessary, tie the first floor to the grade beam foundations with positive anchorage (lower priority). A preliminary estimate of the cost of this structural upgrade is $20/sf or $344,000 plus fees for permits, engineering design, inspection, and project management, which would bring the total cost to about $430,000. A10.1.2 Benefit-Cost Analysis of Suggested Structural Retrofit The vulnerability of the Monroe High School original building to seismic damages is expressed by the fragility curves given in Section 5.3 of the Phase Two Technical Appendix, which are shown below in Table A10-1. Table A10-1 Fragility Curves for Monroe High School Original Building Building Damage States (median PGA for damage state, g) Building Status Slight Moderate Extensive Complete Uncertainty Parameter (beta) As-Is 0.11 0.17 0.25 0.35 0.70 After Retrofit 0.20 0.30 0.70 1.00 0.66 The fragility curve data above, which are somewhat complex mathematically, represent the probabilities that the building will be in a given damage state at each level of ground 10-33 shaking (PGA, peak ground acceleration), expressed relative to the acceleration of gravity, g. Some examples of how to interpret these data were given in the discussion of the Albany Fire Station #1 in the Phase Two Earthquake Chapter 4. For benefit-cost analysis, we use the above fragility curves to calculate the expected percentage damage of the building at several levels of ground shaking. The uncertainty parameter (beta) reflects the extent of knowledge about the expected seismic performance of the building. The uncertainty parameter is conceptually similar to the more familiar standard deviation for a normal statistical distribution. For non-technical readers, seismic vulnerability is more easily understood as the expected percentage damage to a building at various levels of ground shaking. Percent damage is always expressed relative to the replacement value of the building, that is, the cost to construct a new building of the same size, function, and level of amenities as the existing building. The percent damage expected for the as-is and after retrofit states of the building are shown below in Table A10-2, for the bins (ranges) of PGA used in the FEMA benefit-cost software. Table A10-2 Building Seismic Vulnerability As-Is and After Retrofit Monroe High School Original Building Percent Damage to Building PGA (g) As-Is After Retrofit 0.04 to 0.08 2.06 0.13 0.08 to 0.16 12.62 1.28 0.16 to 0.32 41.06 7.02 0.32 to 0.55 71.75 22.07 0.55 to 0.80 87.97 41.97 0.80 to 1.00 94.15 57.36 >1.00 97.52 72.01 Table 4-8 shows the estimated percent building damage at various PGA levels. However, it is important to recognize that at high levels of damage, buildings are usually demolished and rebuilt, rather than being repaired. For the purposes of benefit-cost analysis, we assume that building damages of 50% or more of the replacement value result in a complete loss of the building (i.e., demolition and replacement). From the percent building damage, other direct impacts arising from earthquake damage are estimated. We assume that contents are damaged at the same percentage as is the building. We also estimate loss of function impacts, depending on 10-34 the extent of building damages. Casualty rates are also estimated for deaths, major injuries and minor injuries, based on the extent of building damage (more precisely, on the probabilities that a building will be in each of the defined damage states). Estimated casualty rates for this building in the as-is condition are shown below in Table A10-3. Table A10-3 Casualty Rates per 1,000 Occupants Monroe High School, Original Building Casualty Rates per 1000 Occupants PGA (g) Deaths Major Injuries Minor Injuries 0.04 to 0.08 1.23 2.58 4.07 0.08 to 0.16 13 26 33 0.16 to 0.32 60 120 133 0.32 to 0.55 125 251262 0.55 to 0.80 165 331 338 0.80 to 1.00 182 365 369 >1.00 192 385 386 After retrofit, we assume that the retrofit is focused on ensuring life-safety and that casualties are greatly reduced, in accord with the typical assumptions made by FEMA in evaluating seismic hazard mitigation projects. Data inputs and assumptions for the benefit-cost analysis are summarized below in Table A10-4. This analysis is based, in part, on typical values and reasonable estimates, where specific figures for this building were not available. Using more building-specific values would improve the accuracy of the benefit-cost analysis. . 10-35 Table A10-4 Benefit-Cost Analysis Data Inputs and Assumptions Monroe High School, Original Building Parameter Value Used Notes Discount rate 3% Assumed 5% cost of borrowing funds, less 2% inflation, yields 3% real discount rate. For FEMA funded projects, a discount rate of 7% is mandatory, which would lower the calculated benefit-cost ratio by about 46% Project useful lifetime 50 years typical FEMA assumption for public buildings Building replacement value/sf $125 estimate, reproduction value for historic building Contents value $516,000 rough estimate, $30/sf Displacement costs (rent per month per sf) $1.50 typical value Displacement costs, other monthly costs $2500 estimate Displacement costs, one $5000 estimate Annual operating budget $500,000 rough estimate Continuity premium (multiplier on daily cost of service for disaster response services) None not an essential service for disaster response and recovery Functional downtime FEMA typical values typical FEMA assumption for ordinary public services Displacement time FEMA typical values typical values Average Occupancy 26.79 calculated 24-hour average occupancy, from local data In addition to the above data input and assumptions, benefit-cost analysis requires a seismic hazard curve for the site under evaluation. The seismic hazard curve shown below in Table A10-5 was used for this analysis. These data were provided by John Eidinger of G&E Engineering Systems, Inc. (December, 1999), based on his review of the seismicity of western Oregon, including the location of this specific building relative 10-36 to the earthquake source regions. The seismic data sources for these data are summarized in the Phase Two Technical Appendix. Table A10-5 Seismic Hazard Curve Monroe High School PGA (g) Annual Probability Recurrence Interval (years) 0.04 to 0.08 0.01339 75 0.08 to 0.16 0.009167 109 0.16 to 0.32 0.001851 540 0.32 to 0.55 0.0004695 2130 0.55 to 0.80 0.00009290 10764 0.80 to 1.00 0.00001646 60753 >1.00 0.00001400 71429 With all of the above data inputs, the benefit-cost results for the retrofit of this building are as summarized below in Table A10-6 10-37 Table A10-6 Benefit-Cost Results Monroe High School, Original Building Category Benefit (net present value Of avoided damages and losses) Building Damages $129,880 Contents Damages $31,791 Displacement Costs $28,163 Loss of Public Services $7,006 Casualties $1,163,354 Total Benefits $1,360,193 Mitigation Project Costs $430,000 Benefit-Cost Ratio 3.16 The benefit-cost ratio of the seismic retrofit for the Monroe High School original building has a benefit-cost ratio of 3.16 which means that the benefits are three times more than the costs and thus the project is deemed cost-effective or economically justified. The caveats that this analysis is based on a preliminary evaluation of the building, and on a variety of data inputs and assumptions that are subject to refinement, mean that the result may change with better input data. In this example, about 85% of the total calculated benefits arise from avoided casualties. The FEMA statistical values for human life were used for this calculation. Deaths, major injuries, and minor injuries are assumed to have statistical values of $2,200,000, $12,500, and $1,250, respectively. The benefit-cost ratio for the retrofit of the Monroe High School is substantially higher than that calculated above for the Albany Fire Station, in part because of the higher average occupancy of the high school, with a correspondingly higher benefit of reducing casualties. However, the higher substantially higher probability of being in the complete damage state than does the fire station. Thus, for the as-is conditions of the buildings, the level of live safety risk for the high school is higher per unit occupancy as well as higher because of the higher occupancy. The level of seismic hazard for the Monroe site of this school is moderate. One reason that the proposed mitigation project has a BCR above 1 is that the cost of the proposed 10-38 project is low - relative to the replacement value of the building. The preliminary cost estimate of $430,000, includes ONLY a bare-bones seismic structural upgrade of the building and does not include costs for asbestos abatement, ADA compliance, or other upgrades which might be required for non-seismic reasons. For benefit-cost analysis of a seismic hazard mitigation project, we consider only the benefits of the seismic improvements and thus consider only the costs for the seismic upgrade itself. Another important factor in the benefit-cost analysis is the discount rate, which accounts for the time value of money. For seismic retrofits, the costs are incurred up front - in the year the project is built - while the benefits accrue statistically over the useful lifetime of the project - in this case, 50 years. The 3% discount rate is reasonable for locally funded projects. However, for FEMA funded projects, the Office of Management and Budget mandates a discount rate of 7%. This higher discount rate, in effect, discounts future benefits more harshly, and thus would result in a substantially lower benefit cost ratio (by about 46%) than that calculated using a 3% discount rate. Finally, in the broader context of community planning, this analysis only compares the costs and benefits of the proposed seismic retrofit. The analysis does not consider questions such as should the community fund another educational program rather than undertaking this retrofit? In other words, the results of benefit-cost analysis provide very important inputs into the decision-making process, but do not provide an absolute answer. 10-39 11.0 VOLCANIC HAZARDS 11.1 Overview The Cascades, which run from British Columbia through Washington and Oregon into northern California, contain more than a dozen major volcanoes and hundreds of smaller volcanic features. In the past 200 years, seven of the Cascade volcanoes in the United States have erupted, including: Mt. Baker, Glacier Peak, Mt. Rainier, Mount St. Helens, Mt. Hood, Mt. Shasta, and Mt. Lassen. Over the past 4,000 years (a geologically very short time period) there have been three eruptions of Mt. Hood, four eruptions in the Three Sisters area, and two eruptions in the Newberry Volcano area and minor eruptions near Mt. Jefferson, at Blue Lake Crater, in the Sand Mountain Field (Santiam Pass), near Mt. Washington, and near Belknap Crater. During this time period, the most active volcano in the Cascades has been Mount St. Helens with about 14 major eruptions and many smaller eruptions. Many other volcanoes are deemed active or potentially active. The Smithsonian Institution?s Global Volcanism Project lists 20 active volcanoes in Oregon and 7 in Washington. These volcanoes are listed below in Tables 11.1 and 11.2 Table 11.1 Active Volcanoes in Oregon Volcano Type Last Eruption Mt. Hood Stratovolcano 1866 Mt. Jefferson Stratovolcano 950 main volcano inactive for >10,000 years Blue Lake Crater Crater 1490 BC Sand Mountain Field Cinder cones 1040 BC? Mt. Washington Shield volcano 620 main volcano inactive Belknap Field Shield volcanoes 460? North Sister Field Complex volcano 350 South Sister Complex volcano 50 BC? Mt. Bachelor Stratovolcano 5800 BC Davis Lake Volcanic field 2790 BC? Newberry Volcano Shield volcano 620 crater formation 300,000 to 500,000 years ago Devils Garden Volcanic field unknown Squaw Ridge Lava Field Volcanic field unknown Four Craters Lava Field Volcanic field unknown Cinnamon Butte Cinder cones unknown Crater Lake Caldera 2290 BC Crater formation about 7,700 years ago Diamond Craters Volcanic field unknown Saddle Butte Volcanic field unknown Jordan Craters Volcanic field 1250 BC Jackies Butte Volcanic field unknown 11-1 Table 11.2 Active Volcanoes in Washington Volcano Type Last Eruption Mt. Baker Stratovolcano 1880 Glacier Peak Stratovolcano 1700 + 100 Mt. Rainier Stratovolcano 1825 (?) Mt. Adams Stratovolcano 950 AD (?) Mount St. Helens Stratovolcano 1991 (eruptions started in 1980) West Crater Volcanic field 5760 BC (?) Indian Heaven Shield volcanoes 6250 BC + 100 On a longer geological time scale, volcanic activity in the Cascades has been very widespread. A DOGAMI report on prehistoric and historic volcanic eruptions in Oregon (see website below) notes that over 3,000 large and small volcanoes have erupted over the past five million years, in the Cascades as a whole. Within historical times, between 1843 and 1860 there were a series of 21 eruptions in the Cascades and there is some scientific speculation that the Northwest may be entering another period of volcanic activity. A great deal of general background information on Oregon and Washington volcanoes and on volcanoes in general is available on several websites, including the following. Table 11.3 Volcano Websites Institution Website Smithsonian Institution (Global Volcanism Project) www.volcano.si.edu/gvp United States Geological Survey (USGS) - general site www.usgs.gov USGS Cascades Volcano Observatory (Vancouver, WA) http://vulcan.wr.usgs.gov DOGAMI www.oregongeology.com The numerous volcanoes of the Cascades differ markedly in their geological characteristics. The largest volcanoes are generally what geologists call composite or stratovolcanoes. These volcanoes may be active for tens of thousands of years to hundreds of thousands of years. In some cases, these large volcanoes may have explosive eruptions such as Mount St. Helens in 1980 or Crater Lake about 7,700 years ago. The much more numerous sites of volcanic activity are generally what geologists call mafic volcanoes. This type of volcano is typically active for much shorter time periods, up to a few hundred years, and generally forms small craters or cones. Mafic volcanoes are not subject to large explosive events. 11-2 11.2 Volcanic Hazard Types In Oregon, awareness of the potential for volcanic eruptions was greatly increased by the May 18, 1980 eruption of nearby Mount St. Helens in Washington that killed 57 people. In this eruption, lateral blast effects covered 230 square miles and reached 17 miles northwest of the crater, pyroclastic flows covered six square miles and reached 5 miles north of the crater, and landslides covered 23 square miles. Ash accumulations were about 10 inches at 10 miles downwind, 1 inch at 60 miles downwind, and ? inch at 300 miles downwind. Lahars (mudflows) affected the North and South Forks of the Toutle River, the Green River, and ultimately the Columbia River as far as 70 miles from the volcano. Damage and reconstruction costs exceeded $1 billion. Volcanic eruptions often involve several distinct types of hazards to people and property, as well evidenced by the Mount St. Helens eruption. Major volcanic hazards include: lava flows, blast effects, pyroclastic flows, ash flows, lahars, and landslides or debris flows. Some of these hazards (e.g., lava flows) only affect areas very near the volcano. Other hazards may affect areas 10 or 20 miles away from the volcano, while ash falls may affect areas many miles downwind of the eruption site. Lava flows are eruptions of molten rock. Lava flows for the major Cascades volcanoes tend to be thick and viscous, forming cones and thus typically affecting areas only very near the eruption vent. However, flows from the smaller mafic volcanoes may be less viscous flows that spread out over wider areas. Lava flows obviously destroy everything in their path. Blast effects may occur with violent eruptions, such as Mount St. Helens in 1980. Most volcanic blasts are largely upwards. However, the Mount St. Helens blast was lateral, with impacts 17 miles from the volcano. Similar or larger blast zones are possible in future eruptions of any of the major Cascades volcanoes. Pyroclastic flows are high-speed avalanches of hot ash, rock fragments and gases. Pyroclastic flows can be as hot as 1500 oF and move downslope at 100 to 150 miles per hour. Pyroclastic flows are extremely deadly for anyone caught in their path. Ash falls result when explosive eruptions blast rock fragments into the air. Such blasts may include tephra (solid and molten rock fragments). The largest rock fragments (sometimes called ?bombs?) generally fall within two miles of the eruption vent. Smaller ash fragments (less than about 0.1?) typically rise into the area forming a huge eruption column. In very large eruptions, ash falls may total many feet in depth near the vent and extent for hundreds or even thousands of miles downwind. Lahars or mudflows are common during eruptions of volcanoes with 11-3 heavy loading of ice and snow. These flows of mud, rock and water can rush down channels at 20 to 40 miles an hour and can extend for more than 50 miles. For some volcanoes, lahars are a major hazard because highly populated areas are built on lahar flows from previous eruptions. Landslides or debris flows are the rapid downslope movement of rocky material, snow and/or ice. Volcano landslides can range from small movements of loose debris to massive collapses of the entire summit or sides of a volcano. Landslides on volcanic slopes may be triggered by eruptions or by earthquakes or simply by heavy rainfall. 11.3 Volcanic Hazards for Benton County Several of the active volcanoes in Oregon and Washington (See Tables 11.1 and 11.2) are located relatively near Benton County, including Mount St. Helens and Mt. Hood. Approximate distances from Corvallis to three relatively nearby volcanoes are shown below in Table 11.4. Table 11.4 Distances from Corvallis Volcano Distance (miles) Mount St. Helens 112 Mt. Hood 92 Three Sisters 80 Among these relatively nearby volcanoes, Mount St. Helens is the most active. Mt. Hood and the Three Sisters are definitely active. Benton County is approximately 80 miles from the Three Sisters, and further away from the other volcanoes. We review the volcanic hazards posed by the Three Sisters the nearest active volcano that may affect Benton County. Awareness of potential volcanic activity at the Three Sisters has been raised because of the recent discovery of an uplift (bulge) on the west side of South Sister. In May 2001, the USGS announced that it had detected a slight swelling or uplift of the west side of South Sister. This bulge, which occurred between 1996 and 2000, covers an area about 9 to 12 miles in diameter, with a maximum bulge in the center of about 4 inches. The cause of this uplift (bulge) is most likely intrusion of a small amount of magma (molten rock) deep under the surface, probably at a depth of about 4 miles. This observation confirms that South Sister is still an active volcano, but needs to be interpreted cautiously. For comparison, a bulge was also observed on the north side of Mount St. Helens in the months prior to the May 18, 1980 eruption. However, the Mount St. Helens bulge was 450 feet high and growing at a rate of 5 feet per day prior 11-4 to the eruption. Thus, the South Sister bulge of 4 inches is certainly not an indication of an imminent eruption. The USGS analysis of Volcano Hazards in the Three Sisters Region, Oregon was published in 1999 (Open-File Report 99-437). Its main conclusions are summarized in the following paragraphs. The Three Sisters area includes two large composite volcanoes (Middle and South Sister). Large composite volcanoes in the Cascades (e.g., Mt. Hood, Mt. Jefferson, Newberry Volcano, Crater Lake) are often active for hundreds of thousands of years and are subject to sometimes-explosive eruptions (e.g., Mount St. Helens in 1980). Hazards from eruptions of composite volcanoes include all of the hazards listed above in Section 11.2. Between the major composite volcanoes, the crest of the Cascades is built up of hundreds of ?mafic? volcanoes. Mafic volcanoes typically erupt for a few weeks to a few centuries, although some can be nearly as large as the composite volcanoes. Prominent mafic volcanoes in the Three Sisters area include North Sister, Mount Bachelor, Belknap Cater, Black Butte, and Mount Washington. Mafic volcanoes often form broad fields of volcanic vents such as in the Sand Mountain Field near the Santiam Pass, north of the Three Sisters. Mafic volcanoes typically erupt less explosively than do composite volcanoes, so that impacts of eruptions are less widespread. Most mafic eruptions in the Three Sisters areas have produced tephra deposits and lava flows that typically traveled 3 to 9 miles from the vents and rarely 9 to 12 miles from the vents. Tephra deposits rarely exceed 4 inches in thickness at distances 6 miles from the vent. Belknap Crater, about 1,500 years old, is one of the youngest mafic volcanoes in the Cascades. The Sand Mountain field, a cluster of cones and lava flows west of Santiam Pass, was formed during three eruptive periods between about 2,000 and 4,000 years ago. The USGS study of Volcano Hazards in the Three Sisters Region includes three hazard zones: proximal hazards, distal hazards, and a regional lava flow hazard zone. The proximal hazard zone is limited to the immediate area around the Three Sisters and is an oval area about 8 miles (east-west) by 10 miles (north-south). The proximal hazard area is the area subject to the most intense volcanic hazards including lava flows, tephra flows, pyroclastic flows, landslides and debris flows and lahars. Fortunately, this area is predominantly wilderness with very low population. The distal hazard zones are river valleys extending away from the proximal hazard zone that are subject to landslides, debris flows and lahars. The distal hazard zone has three levels for areas subjected to 11-5 lahars (and other flows) of varying sizes. Areas subjected to lahars include Squaw Creek into Sisters, Tumalo Creek into Bend, the valley between Sparks Lake and Crane Prairie Reservoir, and the McKenzie River (and tributaries) west of the Three Sisters. The regional lava flow hazard zone includes a band about 30 to 40 miles wide covering the entire crest of the Cascades. Locations throughout this zone, which includes Sisters, Bend, and the Santiam Pass, are subject to lava flows from mafic volcanism would could occur anywhere in this entire zone. None of these Three Sisters volcanic hazard zones impact Benton County directly. Thus, the extent of volcanic hazards for Benton County appears largely limited to the possibility of minor ash falls from eruptions at, Three Sisters, at other locations in the Cascades (e.g., Mount St. Helens). In all but the most extreme events, ash falls in Benton County are likely to be minor with an inch or less of ash likely. Volcanic events in the Three Sisters area or in the Santiam Pass area (Sand Mountain volcanic field) could also close eastbound Highway 20 and thus affect transportation to/from Benton County, at least to a very limited extent. However, to a much lower extent, volcanic activity at Three Sisters could affect Benton County in several ways: 1) Depending on the volume of volcanic ash ejected by an eruption and on prevailing wind directions at the time of eruption, various thicknesses of ash falls may affect Benton County. Possible impacts of ash falls include: a) Clean-up and debris removal, b) Possible respiratory problems for at-risk population such as elderly, young children or others with respiratory problems, c) Possible impacts on public water supplies drawn from surface waters, including degradation of water quality (high turbidity) and possible increased maintenance requirements at water treatment plants, and d) Possible electric power outages from ash-induced short circuits in distribution lines, transmission lines, and substations. 2) Debris flows, landslides, and lahars into the river valleys near the Three Sisters may affect the McKenzie River and the Willamette River downstream and thus also affect public water supplies downstream. The following maps show probabilistic data on ash fall in western Oregon, taking into 11-6 account all of the active volcanoes (USGS Open File Report 9-437, Plate 1, 1999). Interpolating between the map contours of Figure 11.5, the annual probability of 1 centimeter (about 0.4 inch) or more of volcanic ash is about 1/5000 in Benton County. In other words the return period for such ash falls are about 5,000 years for various locations within Benton County. Interpolating between the map contours of Figure 11.6, the annual probability of 10 centimeters (about 4 inches) or more of volcanic ash is less than 1/10,000. In other words the return period for such ash falls are greater than 10,000 years for various locations within Benton County. Figure 11.5 Annual Probability of 1 Centimeter (about 0.4 inch) or More of Volcanic Ash 11-7 Figure 11.6 Annual Probability of 10 Centimeters (about 4 inches) or More of Volcanic Ash (same scale as Figure 11.5 above) The low probabilities of significant ash falls (i.e., long return periods) arise because ash falls in Benton County require volcanic eruptions producing ash and wind directions that deposit ash westward from the volcanoes. For the 2004 eruptions of Mount St. Helens (and presumably for future eruptions of Mount St. Helens and other volcanoes in the Cascades), NOAA has real time volcanic ash forecasts, taking into account eruption locations and wind directions. These forecasts are available at: http://www.arl.noaa.gov/ready/vaftadmenu To see specific ash forecasts for Mount St. Helens, click on ?Hypothetical Eruptions? and then select St. Helens and the desired forecast time frame to view the projections. 11-8 The probable impacts of potential volcanic eruptions on Benton County are summarized below in Table 11.7. Table 11.7 Probable Impacts of Potential Volcanic Eruptions on Benton County Inventory Probable Impacts Portion of Benton County Affected Entire County and surrounding region may be affected by ash falls from some eruptions. Buildings Negligible impact, other than minor cleanup required Streets within Benton County Negligible impact, other than minor cleanup required Roads to/from Benton County Negligible impact, other than minor cleanup required Electric Power Temporary power outages possible from short circuits caused by ash falls Other Utilities Negligible impact, other than minor cleanup required for most utilities. Potential to impact water treatment plants which may require additional maintenance to deal with high turbidity water Casualties Some potential for health impacts, especially for frail people with respiratory problems. 11.4 Mitigation of Volcanic Hazards Mitigation of volcanic hazards is predominantly in the areas of monitoring volcanic activity, warnings and evacuation, and emergency response. That is, there are few, if any, practical physical measures to mitigate the direct impacts of volcanic activity. The USGS actively monitors volcanic activity in the Cascades via networks of seismic sensors (which can detect earthquakes related to magma movements) as well as very accurate ground surface measurements, such as that which has detected the very small bulge on South Sister. The USGS also has a volcanic warning system with several levels of alert as a potential eruption becomes more likely and more imminent. For the Cascades, the USGS volcano warning system (www.usgs.gov) has three levels. Level One (Volcanic Unrest) means anomalous conditions that could be indicative of an eventual volcanic eruption. Level Two (Volcanic Advisory) means that processes are underway that have a significant likelihood of culminating in hazardous volcanic activity, but when the evidence does not indicate that a life- or property-threatening event is imminent. Level Three (Volcano Alert) means that monitoring or evaluation indicate that precursory events have escalated to the point where a volcanic event with attendant volcanologic or hydrologic hazards threatening to life and property appears imminent or is underway. For most of Benton County, which is located well outside of any of the likely direct hazard zones for any Cascades volcanic events, mitigation for volcanic activity is likely a low priority. In the event of a minor ash fall, public warnings directing people (especially those with respiratory problems) to remain indoors, and minor cleanup are most likely the only necessary responses for most volcanic effects impacting Benton County. In addition, water treatment plants should be evaluated to ensure that they could handle possible high turbidity events from volcanic ash falls into water supplies. 11-9 11-10 The following table includes the volcanic hazards mitigation action items from the master Action Items table in Chapter 4. Table 11.8 Volcanic Hazards Mitigation Action Items Mitigation Plan Goals Addressed Hazard Action Item Coordinating Organizations Timeline Life Safety Critical Facilities and Emergency Services Protect Property Disaster Resilient Economy Public Education, Outreach, Partnerships Volcanic Hazards Mitigation Action Items Short-Term #1 Update public emergency notification procedures for ash fall events CRCC, Benton County Emergency Management 1-2 Years X X X Short-Term #2 Update emergency response planning for ash fall events local emergency services agencies 1-2 Years X X X Short-Term #3 Evaluate capability of water treatment plants to deal with high turbidity from ash falls and upgrade treatment facilities and emergency response plans to deal with ash falls local water agencies 1-2 Years X X X X X Short-Term #4 Evaluate ash impact on storm water drainage system and develop mitigation actions if necessary public works agencies 1-2 Years X X X X 11-11 This Page Left Blank 11-12 12.0 DAM SAFETY 12.1 Overview of Dams Dams are manmade structures built to impound water. Dams are built for many purposes including water storage for potable water supply, livestock water supply, irrigation, or fire suppression. Other dams are built for flood control, recreation, navigation, hydroelectric power or to contain mine tailings. Dams may also be multifunction, serving two or more of these purposes. The National Inventory of Dams, NID, which is maintained by the United States Army Corps of Engineers, is a database of approximately 76,000 dams in the United States. The NID does not include all dams in the United States. Rather, the NID includes dams that are deemed to have a high or significant hazard potential and dams deemed to pose a low hazard if they meet inclusion criteria based on dam height and storage volume. Low hazard potential dams are included if they meet either of the following selection criteria: 1) exceeds 25 feet in height and 15 acre-feet of storage, or 2) exceeds 6 feet in height and 50-acre feet of storage. There are many thousands of dams too small to meet the NID selection criteria. However, these small dams are generally too small to have significant impacts if they fail and thus are generally not considered for purposes of risk assessment or mitigation planning. This NID potential hazard classification is solely a measure of the probable impacts if a dam fails. Thus, a dam classified as High Potential Hazard does not mean that the dam is unsafe or likely to fail. The level of risk (probability of failure) of a given dam is not even considered in this classification scheme. Rather, the High Potential Hazard classification simply means that there are people at risk downstream from the dam in the inundation area, if the dam were to fail. The NID potential hazard classification system for dams is as summarized below in Table 12.1. Table 12.1 NID Hazard Potential Classification for Dams1 Hazard Potential Classification Loss of Human Life Economic, Environmental, or Lifeline Losses Low None expected Low and generally limited to dam owner Significant None expected Yes High Probable, one or more expected Yes, but not necessary for this classification. Dams assigned the low hazard potential classification are those where failure or mis- 12-1 operation results in no probable loss of human life and low economic and/or environmental losses. Losses are principally limited to the dam owner?s property. Dams assigned to the significant hazard potential classification are those where failure or mis-operation results in no probable loss of human life but can cause economic loss, environmental damage, or disruption of lifeline facilities. Significant hazard potential dams are often located in predominantly rural or agricultural areas. Dams assigned to the high hazard potential classification are those where failure or mis- operation will probably cause loss of human life. Failure of dams in the high classification will generally also result in economic, environmental or lifeline losses, but the classification is based solely on probable loss of life. Of the dams in the NID, nearly 60% are privately owned. In addition to the dams in the NID, there are many thousands of dams too small to meet the selection criteria for the NID. Most of these small dams are also privately owned. The NID is available online through several links at FEMA and the United States Army Corps of Engineers. However, since September 11, 2001, access is somewhat restricted. Basic NID information and links to the database are available at http://crunch.tec.army.mil/nid/webpages/nid.cfm 12.2 Dam Primer In the simplest terms, dams are impervious structures that block the flow of water in a river or stream and thereby impound water behind the dam. Dams have been built for thousands of years from a wide range of materials, including earth, stone, masonry, wood, and concrete. Large modern dams are almost always embankment dams (built primarily from soil, rock, or mixtures) or concrete dams. Large modern dams almost always have control mechanisms such as gated spillways or outlet pipes for releasing water in a controlled fashion. Typically, dams are operated to smooth natural variations in water flow. During high water flow periods, water is stored behind a dam, while in low water flow periods, water is released to increase flows. Controlled releases typically result in lower peak (flood) flows and higher minimum flows than in uncontrolled streams. The specific patterns of water storage and release vary from dam to dam, depending on the primary purpose(s) of the dam and on a wide variety of economic, regulatory and environmental considerations. 12.2.1 Dam Nomenclature and Types of Dams Modern dams, whether embankment dams or concrete dams, are typically constructed on a foundation, which may be concrete, natural rock or soils, or compacted soils. Dams are usually constructed along a constricted part of a river valley to minimize cost. Dams are also connected to the surrounding natural valley walls, which become the abutments of the dam structure itself. 12-2 Embankment dams are commonly termed earthfill or rockfill dams, depending on the primary material used in their construction. Historically, a wide range of earth and rock materials have been used to construct embankment dams, with various construction techniques including hydraulic fill and compaction. Embankment dams are broad flat structures, typically at least twice as wide at the base as their height. In cross section, embankment dams are typically trapezoidal, with a wide flat base, sloping slides and a narrower flat top. Depending on the permeability of the materials used in an embankment dam, impervious layers may be added to the upstream side of the structure or in the center core of the structure. Embankment dams are subject to erosion by running water. Thus, modern embankment dams always have erosion-resistant materials used in the water release and control mechanisms of the dam. Typically, concrete spillways with concrete or steel gates are used to control releases. Many dams also have outlet pipe systems with concrete or steel pipes as part of the water release control system. Modern concrete dams fall into two major classes: gravity dams and arch dams. Concrete gravity dams are designed on principles similar to embankment dams. Concrete gravity dams are broad structures, generally triangular in shape with a flat base, a narrow top, a flat upstream side and a broad sloping downstream side. Much of these dams? capacity to impound water arises from the weight of the dam. Typically, gravity dams are keyed into bedrock foundations and abutments to increase the stability of the dam. Concrete arch dams rely primarily on the strength of concrete to impound water. Concrete arch dams are much thinner in cross section than concrete gravity dams and are always convex on the upstream side and concave on the downstream side because concrete is much stronger in compression than in tension. With this arch design, the pressure of impounded water compresses the concrete and makes the dam stronger. Like concrete gravity dams, concrete arch dams are also keyed into bedrock foundations and abutments to provide stability. A less common variation of a concrete arch dam is a concrete buttress dam. Buttress dams are arched or straight dams with additional strength provided by buttresses perpendicular to the long axis of the dam. An excellent introduction to dam nomenclature and descriptions of types of dams is given in the FEMA publication: Dam Safety: An Owner?s Guidance Manual.3 For further details, the reader is referred to this publication and the references therein. 12.2.2 Dam Failure Modes Dam failures can occur at any time in a dam?s life; however, failures are most common when water storage for the dam is at or near design capacity. At high water levels, the water force on the dam is higher and several of the most common failure modes are more likely to occur. Correspondingly, for any dam, the probability of failure is much lower when water levels are substantially below the design capacity for the reservoir. 12-3 For embankment dams, the most common failure mode is erosion of the dam during prolonged periods of rainfall and flooding. When dams are full and water inflow rates exceed the capacity of the controlled release mechanisms (spillways and outlet pipes), overtopping may occur. When overtopping occurs, scour and erosion of either the dam itself and/or of the abutments may lead to partial or complete failure of the dam. Especially for embankment dams, internal erosion, piping or seepage through the dam, foundation, or abutments can also lead to failure. For smaller dams, erosion and weakening of dam structures by growth of vegetation and burrowing animals is a common cause of failure. For embankment dams, earthquake ground motions may cause dams to settle or spread laterally. Such settlement does not generally lead, by itself, to immediate failure. However, if the dam is full, relatively minor amounts of settling may cause overtopping to occur, with resulting scour and erosion that may progress to failure. For any dam, improper design or construction or inadequate preparation of foundations and abutments can also cause failures. Improper operation of a dam, such as failure to open gates or valves during high flow periods can also trigger dam failure. For any dam, unusual hydrodynamic (water) forces can also initiate failure. Landslides into the reservoir, which may occur on their own or be triggered by earthquakes, may lead to surge waves that overtop dams or hydrodynamic forces that cause dams to fail under the unexpected load. Earthquakes can also cause seiches (waves) in reservoirs that may overtop or overload dam structures. In rare cases, high winds may also cause waves that overtop or overload dam structures. Concrete dams are also subject to failure due to seepage of water through foundations or abutments. Dams of any construction type are also subject to deliberate damage via sabotage or terrorism. For waterways with a series of dams, downstream dams are also subject to failure induced by the failure of an upstream dam. If an upstream dam fails, then downstream dams also fail due to overtopping or due to hydrodynamic forces. An excellent review of the common mechanisms for dam failures is given in the FEMA publication: Dam Safety: An Owner?s Guidance Manual.3 For further details, the reader is referred to this publication and the references therein. A National Research Council study4 of dam failures in the United States and Western Europe from 1900 to 1969 compiled historical data on the observed probability of failure as a function of type of dam. Dam failures are quite common in the United States. For example, FEMA data from Tropical Storm Alberto (1994) show 230 dam failures in the State of Georgia from this single event.5 Fortunately, most dam failures are of small dams where the failure poses little or no risk to life safety and only minor, localized property damage. Most failures are of dams that are too small to be included in the NID database or dams in the NID Low Hazard Potential Category. However, in the United States between 1960 and 1997 there were 23 dam failures that caused at least one death, with total fatalities from these 23 failures estimated at 318 12-4 people.5 Since 1874, there have been six dam failures in the United States which killed over 100 people.2 The worst dam failure, in terms of casualties, was the 1889 Johnstown Pennsylvania dam failure which killed over 2,200 people. Three of the high fatality dam failures occurred in the 1970s: Black Hills, South Dakota, Big Thompson River, Colorado, and Buffalo Creek, West Virginia. These three failures alone resulted in an estimated 514 deaths.2 (Note: the published death statistics in this paragraph from these two FEMA sources are inconsistent, but these differences are not significant for the present purposes). 12.3 Oregon Dam Data The National Inventory of Dams (NID) lists 812 dams in Oregon. Of these NID dams, 9 are in Benton County. The statistical breakdown of these dams by NID Potential Hazard Categories is shown below in Table 12.2. For Oregon, there are 128 dams in the High Potential Hazard Category. Table 12.2 Numbers of Dams by NID Potential Hazard Categories NID Hazard Oregon Benton County High 128 1 Significant 151 1 Low 521 4 Undetermined 12 3 Total 812 9 There is only one dam in Benton County in the High Potential Hazard Category, the North Fork Dam owned by the City of Philomath, which is shown below in Table 12.3. Table 12.3 NID High Potential Hazard Dams in Benton County County Dam Name River City NID Height (feet) NID Storage (acre feet) Benton North Fork Dam North Fork Rock Creek Philomath 83 305 However, Benton County is also potentially at risk from dams upstream along the Willamette River and its tributaries, including 9 dams in Lane County that are in the High Potential Hazard Category. These 9 dams, all of which are federally owned and 12-5 operated are listed individually in Table 12.4 below. Table 12.4 NID High Potential Hazard Dams Affecting Benton County County Dam Name River City NID Height (feet) NID Storage (acre feet) Lane Cottage Grove Coast Fork Willamette River COTTAGE GROVE 103 50,000 Lane Dexter Middle Fork Willamette River EUGENE 117 29,900 Lane Fall Creek Fall Creek SPRINGFIELD 205 125,000 Lane Dorena Row River COTTAGE GROVE 154 131,000 Lane Lookout Point Middle Fork Willamette River EUGENE 276 477,700 Lane Blue River Dam Blue River SPRINGFIELD 312 89,000 Lane Hills Creek Middle Fork Willamette River OAKRIDGE 341 356,000 Lane Cougar South Fork McKenzie River SPRINGFIELD 519 219,000 Lane Fern Ridge Long Tom River EUGENE 49 121,000 All of these NID High Potential Hazard dams are upstream from the Corvallis and Albany metropolitan areas and thus have a potential impact on the largest population centers in Benton County. 12.4 Dam Failure Hazard Assessment: Benton County A 1987 report6 on Dam/Levee Failure by the Oregon Emergency Management Division lists 51 historical dam failures in Oregon from 1896 through the 1980s. As of the time of this report, no dam failure fatalities had been recorded in Oregon. However, the potential for dam failure fatalities certainly exists in Oregon and in Benton County, albeit with a low probability of occurrence. To evaluate the level of risk posed by dams in Benton County, we consider primarily dams in the NID high potential hazard classification. Dams in the significant and low potential hazard categories do not pose a life safety threat and the risk of property damage is minimal or low. For completeness, we note that the NID database of dams for Benton County contains two other small dams that are not rated in the potential hazard classification. These dams are listed below in Table 12.5. Because of their small size, the potential impacts of failure are much smaller than for larger dams. However, if there are people living in the inundation areas, there may be some level of life safety risk. Each of these dams may warrant further investigation of possible life safety risk. 12-6 Table 12.5 NID Dams in Benton County Not Rated for Potential Hazard County Dam River Storage (acre feet) Year Complete d Benton Snellstrom-Eugene Log Pond Amazon Creek 85 1950 Benton Konyn Waste Lagoon Muddy Creek 50 1999 Additional data on the ten NID high potential hazard dams affecting Benton County are given below in Tables 12.6 and 12.7. As shown below, the North Fork Dam does not have an Emergency Action Plan; however, all of the Corps dams do have EAPs. Table 12.6 Additional Data on NID High Potential Dam in Benton County County Dam Name River NID Storage (acre feet) Date Built Dam Type EAP Owner Benton North Fork Dam North Fork Rock Creek 305 1960 RE NO Philomath Table 12.7 Additional Data on NID High Hazard Potential Dams Affecting Benton County County Dam Name River Storage (acre feet) Date Built Dam Type EAP Owner Lane Cottage Grove Coast Fork Willamette 50,000 1942 RE Y Corps Lane Dexter Middle Fork Willamette 29,900 1955 RE Y Corps Lane Fall Creek Fall Creek 125,000 1965 ER Y Corps Lane Dorena Row River 131,000 1949 RE Y Corps Lane Lookout Point Middle Fork Willamette 477,700 1953 RE Y Corps Lane Blue River Dam Blue River 89,000 1968 RE Y Corps Lane Hills Creek Middle Fork Willamette 356,000 1962 RE Y Corps Lane Cougar South Fork McKenzie 219,000 1964 ER Y Corps Lane Fern Ridge Long Tom 121,000 1941 RE Y Corps The NID dam type classification includes the following types of dams: RE rockfill/earthfill embankment dams, primarily rockfill (fill >3? size) ER rockfill/earthfill embankment dams, primarily earthfill (fill <3? size) These dams were completed between 1941 and 1968. All dams are rockfill/earthfill embankment dams. All dams are operated by the US Army Corps of Engineers and all have emergency operations plans in place. All Corps dams are maintained on a regular 12-7 schedule and undergo regular inspections, with major re-inspections every five years. Furthermore, the Corps is highly experienced in the construction, operation, and maintenance of dams. As noted previously, the NID classification as High Potential Hazard means only that there is probable loss of life if one of these dams fails. The NID classification contains no information whatsoever about the safety or lack of safety of a given dam and no information about the probability of failure. For embankment dams, as discussed above, the most common failure modes are overtopping, foundation failures, and seepage through the dam. For concrete dams, the most common failure modes are overtopping and foundation failures. Under normal or flood conditions, failure of the Corps operated dams appears highly unlikely. Failure is perhaps possible, however, in extreme flood events well above the design basis, especially if the reservoirs were close to full at the onset of flooding. The spillway capacities could be exceeded with a potential for overtopping failures. There are, however, two other circumstances that may pose significant threats to any of these dams: landslides and earthquakes. A major landslide into a reservoir, whether triggered by seismic activity or not, could result in a large surge wave that could result in dam failure from a combination of overtopping and hydrodynamic forces. A major earthquake, either a Cascadia Subduction Zone earthquake, or a smaller, interplate or intraplate earthquake in Western Oregon, could cause sufficient damage to these dams to pose a risk of failure. 12.5 Risk Assessment (Preliminary) Each of these major dams which pose a potential life safety hazard for Benton County are operated by the United States Army Corps of Engineers. The Portland District of the Corps, Geotechnical Engineer Branch, Concrete and Dam Safety Section has safety responsibilities for these dams. As of early 2004, the Dam Safety Coordinator was Jim Hinds, whose phone number is (503) 808-4846. A variety of dam safety related information is also available on the Portland District?s web site at www.nwp.usace.army.mil. Under the Corps normal dam operating practices, dams are inspected annually, with a more complete evaluation every five years on a rotating schedule. 12.5.1 Flood Damage to Dams All of the Corps dams were designed and built with specific flood capacities. Current dam designs are based on Standard Project Floods. Standard Project Floods, as defined in the Corps Engineer Manual 1110-2-1411 (March 1, 1965) are floods resulting 12-8 from the Standard Project Storm. In turn, the Standard Project Storm is defined, somewhat imprecisely, as the most severe flood-producing rainfall-snowmelt, depth- area-duration event that is considered ?reasonably characteristic? of the drainage basin. Discussions with Corps staff in the Portland District Office indicated that the Standard Project Flood is approximately a 500-year flood event. The Corp dams? discharge design levels include the combination of spillway discharge capacity and reservoir outlet pipe discharge capacity. As an example, for the Hills Creek Dam, the Standard Project Flood is 64,500 cubic feet per second. The maximum controlled discharge capacity of the dam is 151,760 cubic feet per second, or nearly two and one-half times the Standard Project Flood discharge. These data are included on the Hills Creek Project, Emergency Response Flowchart7. At discharges beyond the maximum controlled discharge capacity of the dam, the dam would be overtopped, discharges would be uncontrolled, and there would be a high probability of damage to the dam, with some potential for dam failure. The large margin of safety in the discharge capacity of the dam suggests that the Hills Creek Dam likely has the capacity to withstand floods at least as large as a 1,000-year flood event without expected damage. 12.5.2 Earthquake Damage to Dams All of these dams were designed and built in the 1940s to 1960s. Seismic design considerations were thus significantly lower than current seismic design considerations. A summary tabulation of the seismic design basis and inspection history of these dams is given below in Table 12.8 (Corps of Engineers, Portland District Office, March, 2001). Table 12.8 Seismic Design, Evaluation and Inspection Data Corps of Engineers Dams Seismic Design Basis Dam Date of Last Seismic Evaluation Original Current Date of Last Periodic Inspection Cottage Grove 1981 None 0.21 g 1997 Dexter 1981 0.10 g 0.21 g 1996 Fall Creek 1981 0.10 g 0.21 g 1999 Dorena 1981 none 0.21 g 1997 Lookout Point 1981 0.10 g 0.21 g 1999 Blue River 1994 0.10 g 0.24 g 1996 Hills Creek 2000 0.10 g 0.22 g 1999 Cougar 1994 0.10 g 0.24 g 1997 Fern Ridge 2001 none 0.35 g 2000 As shown in Table 12.8, the Corps has conducted at least preliminary seismic evaluations of all of these dams. However, some of these evaluations were conducted 12-9 in the 1980s and thus do not reflect current understanding of the seismic hazard in Oregon or current state-of-the-art seismic evaluation engineering principles. The Corps has an ongoing regular inspection program and an ongoing seismic evaluation program. Presumably, updated seismic evaluations of these dams will be completed over the next few years. Seismic considerations were completely absent in the design of two of these dams: Dorena and Fern Ridge. The others were explicitly designed or probably designed to ground shaking levels of 0.10 g, which is the maximum seismic design level for any of the Corps dams in western Oregon. In contrast, the current Corps seismic design levels for dams at these sites (i.e., if new dams were to be built today) would be 0.21 g to 0.24g for the dams in eastern Benton County and 0.35 g for Fern Ridge . Thus, current seismic design requirements are for levels of ground shaking about two times higher than the probable design levels for most of these dams and about three times higher for Fern Ridge. Seismic evaluations of dam safety are a highly technical, highly specialized art. Separate evaluations must be done for each dam. The evaluation requires a detailed analysis of the design and construction of the dam, an analysis of the current condition of materials and components, geotechnical analysis of the foundation and site, and a site-specific seismic hazard analysis. For emergency planning purposes, a seismic evaluation should include the probabilities of failure for a scenario earthquake such as a large magnitude event on the Cascadia Subduction Zone. 12.5.3 Loss Estimates (Preliminary) Detailed loss estimates for possible failures of these dams are beyond the scope of this mitigation plan. However, we note that in 1987 the Oregon Emergency Management Division6, estimated that a completely catastrophic failure of the Hills Creek Dam, an extremely unlikely event, could require the evacuation of over 250,000 people with damages in excess of $10 billion. Adjusting these 1987 estimates for inflation and for population growth suggests that damages could easily exceed $20 billion. Detailed casualty estimates have not been made for catastrophic dam failures affecting Benton County. However, given the large inundation areas, high water depths, and the logistical difficulties in evacuating 250,000 people to safe ground, it is not difficult to imagine that a truly catastrophic dam failure could potentially result in 1,000 or more deaths. The probability of catastrophic failure of these dams is impossible to estimate with any accuracy, from present data. Most likely, the probability is less than 0.1% per year (less than once in 1,000 years, on average) and perhaps substantially less. However, the consequences of failure are so high that careful evaluation is certainly warranted. Each of the Corps dams upstream from Benton County has studies showing inundation areas if dams were to fail catastrophically. Generally, these inundation maps show inundation flood boundaries for dam failures under extreme flood conditions and are 12-10 thus an upper bound for inundation areas under other conditions (e.g., earthquake induced dam failure under non-flood conditions). As an example, a portion of the inundation area mapped along the Willamette River is shown below in Figure 12.9. Table 12.9 Sample Dam Inundation Area Map 12-11 The probable impacts of potential dam failures on communities in Benton County are summarized below in Table 12.10 Table 12.10 Probable Impacts of Potential Dam Failures on Benton County Inventory Probable Impacts Portion of Benton County affected Direct impacts limited to mapped inundation areas for very unlikely complete dam failures at the same time as extreme flood events. Buildings Heavy damage in inundation areas, if the above scenario occurs. Streets within Benton County Damage and closures in inundation areas, if the above scenario occurs. Roads to/from Benton County Damage and closures in inundation areas, if the above scenario occurs. Electric power Damage and loss of service in inundation areas, if the above scenario occurs. Other Utilities Damage and loss of service in inundation areas, if the above scenario occurs.. Potential for major damage to water and wastewater treatment plants in extreme events Casualties Potential for casualties (deaths and injuries) in extremely unlikely major dam failures concurrent with extreme floods, depending on warning time available and effectiveness of evacuations 12.6 Mitigation Strategies Possible dam failures affecting Benton County are low probability events, but the potential casualties and economic impacts are high. The combination of low probability but large impacts makes analysis of such situations difficult from both a technical and a public policy perspective. The evaluation is difficult technically because it requires detailed engineering analysis of each dam and careful probabilistic risk analysis. As always, communication with the public must be non-alarmist, but factual, realistic and informative. Recommendations 1. The first step in mitigation planning for dam safety is emergency planning. Emergency planners in Benton County should obtain copies of the inundation maps for each of the major dams to familiarize themselves with the areas of potential flooding. Inundation maps, which are available from the USACE only as paper copies, should be scanned or otherwise entered into LCOG and local GIS mapping systems. For emergency planning, the estimated flood depths and the time periods from dam failure are particularly important. Flood depths and flood times both vary markedly with distance downstream from the dam locations. For emergency planning, key elements include community emergency notification procedures and evacuation planning (routes and traffic control). Because of the very large numbers of potential evacuees, training seminars and scenario exercises are strongly recommended. 12-12 2. All major dams have Emergency Action Plans. These plans should be reviewed to ensure that they are complete and up to date. Emergency planning officials in each county should be fully informed of the detailed consequences of the potential failure of each dam. Public notification and evacuation plans should be updated and tested. For some types of dam failures, for example, those due to extreme floods, there may be some warning time. Decision making procedures, protocols, and procedures for issuing watches, warnings, and evacuation notices should be reviewed and updated and coordinated among all responsible federal, state, and local agencies. 3. Because of the age of these dams, the seismic design basis is significantly below current seismic design requirements. Preliminary seismic evaluations have been done but without sufficient detail to evaluate the probabilities of dam failures. Because of the extreme consequences of potential failure of one or more of these dams, we recommend that detailed seismic evaluations be conducted for all of these dams. References 1. FEMA, Federal Guidelines for Dam Safety: Hazard Potential Classification Systems for Dams, FEMA 333, October 1998. 2. FEMA, Multihazard Identification and Risk Assessment, A Cornerstone of the National Mitigation Strategy, Chapter 20, Dam Failures, 1997. 3. FEMA, Dam Safety: An Owner?s Guidance Manual, FEMA 145, August 1987. 4. National Research Council, Safety of Existing Dams, Evaluation and Improvement, National Academy Press, 1983. 5. FEMA website (www.fema.gov), National Dam Safety Program webpage. 6. Oregon Emergency Management Division, Dam/Levee Failure, Statewide Hazard Analysis, March, 1987. 7. Hills Creek Lake Project, Emergency Response Flowchart, Distributed January 2000, United States Army Corps of Engineers, Portland District, 5 pages. The table on the following page contains dam safety mitigation action items from the master Action Items table in Chapter 4. 12-13 12-14 Table 12.11 Dam Safety Mitigation Action Items Mitigation Plan Goals Addressed Hazard Action Item Coordinating Organizations Timeline Life Safety Critical Facilities and Emergency Services Protect Property Disaster Resilient Economy Public Education, Outreach, Partnerships Dam Safety Mitigation Action Items Short-Term #1 Prepare high resolution maps of dam failure inundation areas and update emergency response plans, including public notification and evacuation routes Benton County GIS, Benton County Emergency Management, Corps of Engineers, city building departments 1-2 Years X X X Short-Term #2 Identify dikes and owners and the impact of protected structures Benton County GIS, Benton County Emergency Management, Benton County Public Works, city building departments 2-3 years X X X X Long-Term #2 Encourage the Corps of Engineers to complete seismic vulnerability assessments for dams upstream of heavily populated areas in Benton County and to make seismic improvements as necessary Benton County Hazard Mitigation Steering Committee, US Army Corps of Engineers Ongoing X X X X X Long-Term #3 Evaluate the adequacy of dike systems for both floods and earthquakes and implement mitigation measures if necessary Benton County Public Works, US Army Corps of Engineers Ongoing X X X X X 12-15 This Page Left Blank 12-16 13.0 DISRUPTION OF UTILITY AND TRANSPORTATION SYSTEMS The previous chapters dealt with each of the major natural hazards impacting Benton County including floods, winter storms, landslides, wildland/ urban interface fires, earthquakes and volcanic hazards. These chapters evaluated each of the hazards and the risk arising from the hazards as they impact the buildings, infrastructure and people of Benton County. Each of these hazards may result in not only damage to buildings but also damage to and disruption of utility and transportation systems. Mitigation projects may be implemented to reduce or avoid such damage and disruptions and a few examples were discussed in the previous chapters. In this sense, evaluating the potential damage and disruption of utility and transportation systems from each natural hazard is part of the risk assessment for each locality affected by a natural hazard. However, disruption of utility and transportation systems may have impacts on the affected community that are far broader than the direct damage and corresponding direct loss of service. In this sense, disruption of utility and transportation systems may be viewed almost as a hazard. As for other hazards, the probability, duration, and extent of such outages can be assessed and the impacts (risk) associated with such outages can be quantified. Among the major utilities, loss of electric power generally has the most widespread impact on other utilities and on the community as a whole. Therefore, this chapter deals with electric power outages in more detail than for the other utility and transportation systems. 13.1 Transportation Systems Streets, roads, and highways are subject to closure during flood events because of high water levels on road surfaces. This type of closure may occur during either a major flood event on the larger rivers and streams in Benton County and surrounding areas or during winter storms as a result of localized flooding on smaller drainage systems. In major floods or major winter storms, such road closures may be widespread. If flow velocities are low, then such closures are usually due primarily to water depth and there is generally little damage to the road system; reopening the road simply requires waiting for the water level to drop and then cleaning up mud and debris on the road surface. However, if flow velocities are higher then erosion of the road surface or undermining of the road may occur. This type of damage is most common in hilly areas with relatively steep slopes and occurs most often on smaller roads rather than on major highways. Reopening such roads often requires repair of the damaged road surface. The flood of February 1996 provided ample evidence of the impact of flooding on roads. For example, in Benton County, there were dozens of flood-caused road closures. These closures included most of the major routes in the interior of the county and numerous secondary roads. 13-1 For Benton County, Chapter 7 (Winter Storms) identified some of the most problematic areas where major arteries and other roads have been repeatedly affected by winter storms (primarily localized flooding). Some sites of road closures are difficult to mitigate without large-scale flood control projects. However, mitigation is possible at many locations with high potential for road closures. Common measures include raising the road surface to reduce the probability of water overtopping the road or improving local drainage (e.g., culvert upsizings). Risk assessments for road closures must include a measure of the importance of the road for transportation as well as an evaluation of the direct physical damages to the road. In many cases, the disruption of transportation has a larger economic impact that the direct physical damages. To evaluate and prioritize hazard mitigation projects for roads, we suggest three measures of the relative importance of a road: 1) number of vehicle trips per day, 2) detour time around a road closure, and 3) road use as primary access/egress, including emergency vehicles. The number of vehicle trips per day is an obvious measure of the importance of a road. All other factors being equal, a road with 500 trips per day is more important than a road with 50 trips per day and thus should have a higher priority for mitigation projects. However, a better measure of the importance of a road is obtained if the detour time is also considered. If traffic loads were equal, a mitigation project on a road where a closure required a one-hour detour would have a higher priority than a road where a closure only required a five-minute detour. More accurately, it is the combination of traffic load and detour time that provides a measure of the impact of road closure. The product of number of trips per day and the detour time gives a measure of the number of vehicle-hours of delay that result from a closure. Consider the following example: Table 13.1 Calculation of Vehicle-Hours of Delay from Road Closures Road Trips per Day Detour Time (hours) Vehicle- Hours of Delay per day of Closure A 500 0.10 50 B 100 1.00 100 13-2 In this example, Road A has fives times the traffic of Road B, but because the detour time is much longer for a closure on B than on A, the number of vehicle-hours of delay is greater on Road B than on Road A. On this basis, mitigation of the hazard causing the closure would have a higher priority on Road B than on Road A. The number of vehicle hours of delay is a proxy for the economic impact of the closure. The current FEMA value (for benefit-cost analysis purposes) for the economic impact of lost time due to road closures is $32.23 per vehicle hour of delay (What is a Benefit?, FEMA 2001). This value is based on national average wage and benefits level and national average vehicle occupancy data, along with the assumption that an hour of leisure time is worth the same to a person as an hour of work (a common economic assumption). Then, for example, 100 vehicle hours of delay per day has an estimated economic impact of $3,223 and so on. For the vast majority of roads, with ?typical? traffic loads, using an economic value of $32.23 per vehicle per hour of delay provides a reasonable measure of the economic impact of road closures. Everything else being more or less equal, roads that serve as primary access/egress routes and/or serve many emergency vehicles may be given a higher priority for mitigation. For completeness, we note that roads are networked systems and a more accurate analysis of the relative priority of mitigation projects to reduce road closures should consider the network characteristics of a local road system. However, network analysis is complex, requires specialized expertise and is expensive. Network analysis may be justified for very expensive projects, such as a multi-million dollar relocation of a bridge to reduce the potential for flood washouts. However, the simple three-parameter prioritization methodology suggested above is probably sufficient for evaluation of most small to medium sized mitigation projects. Rail systems are subject to the same sorts of closures as are road systems. Evaluation and prioritization of mitigation projects for rail systems would follow a methodology closely analogous to that discussed above for road systems, with economic impact parameters appropriate for a rail system. Other transportation systems (air, ports, ferry) are also subject to disruption due to the impacts of hazards. The analysis of such systems is roughly similar to that discussed above, but mitigation projects for such systems are encountered far less frequently than are mitigation projects for roads. Moreover, most such projects are not directly applicable to or a low priority for Benton County and are thus not considered further. 13.2 Utility Systems - Overview Evaluation of hazard mitigation projects for utility systems have some commonalities between systems that we briefly review before addressing each major utility system in turn. 13-3 Utility systems such as potable water, wastewater, natural gas, telecommunications, and electric power are all networked systems. That is, they consist of nodes and links. Nodes are centers where something happens - such as a pumping plant, a treatment plant, a substation, a switching office and the like. Links are the connections (pipes or lines) between nodes. Risk assessments for utility systems are similar to risk assessments for buildings, in that the inventory of utility components is overlaid on the hazard map and the vulnerability of utility components is evaluated for the hazards impacting the utility. A major difference arises, however, because of the networked nature of utilities. As a simple example, consider an electric utility that suffers damage to 10% of its transmission lines. The extent of service outage might be essentially zero if there are redundant lines with sufficient capacity to handle the demand for electric power. Or, the extent of service outage might be 100% if the damaged lines provide the sole power feed for a community. Thus, the operating characteristics and network characteristics (especially the amount of redundancy) must be considered. In conducting risk assessments or evaluating hazard mitigation projects for utility systems, the networked nature of such systems must be considered. The extent or lack of redundancy for particular elements in a system profoundly affects the extent to which a given level of damage results in system outages. The general procedure for conducting a risk assessment or evaluating a hazard mitigation project for a networked utility system is outlined below in six steps. 1) Overlay utility system components with hazard maps, 2) Estimate the vulnerability of each component to impacts from each hazard, 3) From the estimated amount of damage to the system and the system?s network operating characteristics, estimate the extent and duration of service outage, 4) From the damage estimates and the resources available, estimate the restoration time, 5) From the service outage (number of customers and duration) estimate the economic impacts of such loss of service, and 6) If a mitigation project is being evaluated estimate the reduction in direct damages and the reduction in service interruption attributable to mitigation project. An important caveat for conducting risk assessments or evaluation of hazard mitigation projects for networked utility systems is that specialized expertise is often required. The 13-4 analyst must thoroughly understand the operating characteristics of utility system components and their vulnerability to each hazard as well as thoroughly understand the network operating characteristics of the system as a whole. In the absence of sufficient experience and expertise risk assessments or evaluation of hazard mitigation projects may produce inaccurate and misleading results. CAVEAT: conducting risk assessments or evaluation of hazard mitigation projects of networked utility systems often requires specialized expertise to produce meaningful results. For reference, a detailed discussion of how to evaluate seismic hazard mitigation projects for water systems is given in the American Society of Civil Engineers monograph ?Guidelines for the Seismic Upgrade of Existing Water Transmission Facilities,? (J. M. Eidinger, editor, 1999; chapter by K. A. Goettel ?Seismic Upgrades of Water Transmission Systems: When Is It Worth It??). Very similar principles apply to evaluating hazard mitigation projects for other utility systems for any type of hazard. The following sections briefly review utility systems with emphasis on identifying the system components which are most vulnerable to damage and loss of service from hazards covered in this Mitigation Plan: flooding, winter storms, landslides and earthquakes. Such components are thus logical targets for high priority mitigation projects whenever important components are subject to the hazards. 13.3 Potable Water Systems Water treatment plants, including those in Benton County, are often located in flood prone areas and are subject to inundation when raw water enters the filters, sedimentation or flocculation basins, resulting in loss of capability to treat incoming raw water properly. Water system control buildings and pump stations may also be subject to flood damages. Public or private water systems with wells as the water source are subject to outages when floodwaters contaminate wellheads; this is a common problem for smaller water systems. Water transmission or distribution pipes are rarely damaged by floodwaters, unless there are soil settlements or major erosion, because the lines are sufficiently pressurized (for water quality) to prevent intrusion of floodwaters. Water transmission or distribution pipes are, however, subject to breakage when they cross landslide areas or in earthquakes. Water treatment plants are also subject to earthquake damages to the building and to process and control equipment. Water systems, including Benton County?s water systems, are also highly vulnerable to electric power outages. Many water systems include pumped storage systems where water is pumped to storage tanks that are typically located 60 to 200 feet above the elevation of water system customers. Such tanks generally contain no more than 1 or 2 days of storage beyond typical daily usage (for reasons of water quality). Thus, electric 13-5 power outages of more than 1 or 2 days may result in loss of potable water due to the inability of pumping plants to pump water. The most logical mitigation projects to minimize such outages are to provide back-up generators at key pumping plants or to provide quick connects so that portable generators (if available) can be quickly installed. Water treatment plants are also subject to outages due to loss of electric power. Common mitigation projects for water systems include flood protection for treatment plants, providing back-up power, moving pipes from active landslide areas, and seismic upgrades for treatment plants. 13.4 Wastewater Systems Wastewater systems are often highly vulnerable to flood impacts. Rising water may cause collection pipes to backup and overflow. Intrusion of storm water into collection systems may result in flows that exceed treatment plant capacities, resulting in release of untreated or only partially treated flows. Treatment plants are often located in flood plains, at low elevations, to facilitate gravity flow. However, such locations also facilitate flood damages. Wastewater treatment plans may be inundated, resulting in full or partial plant shutdown or plant bypass with corresponding release of untreated or only partially treated flows. Lift stations and treatment plants are also subject to loss of function due to electric power outages, with resulting overflows or releases. Collection pipes are also subject to breakage due to landslides. However, such impacts are not particularly common, since most wastewater collection systems are in more urbanized areas with only selected areas subject to slides. Wastewater pipes are, however, subject to breakage in earthquakes. Wastewater treatment plants are also subject to earthquake damages to the building and to process and control equipment. Common mitigation projects for wastewater systems include flood protection for wastewater treatment plants, providing back-up power for nodes such as lift stations, moving collection pipes from active landslide areas, and seismic upgrades for treatment plants. 13.5 Natural Gas Systems Natural gas transmission and distribution pipes are not usually affected by flooding, because the pipes are pressurized. However, compressor stations may be subject to inundation damage or loss of electrical power to run electrical and mechanical equipment. Transmission and distribution pipes are also subject to rupture in slide areas. Buried utility pipes are very subject to failure in small ground movements. Movements as small as an inch or two are often sufficient to break the relatively brittle pipe materials. 13-6 Possible mitigation projects for natural gas systems include providing back-up power for important nodes (e.g., compressor stations) and moving pipes from active landslide areas. The potential for fire or explosions from failure of natural gas lines is addressed in Chapter 14 Hazmat. 13.6 Telecommunications Systems Telephone (land lines and cellular) systems, broadcast radio and TV systems, and cable TV systems may all be vulnerable to damages and services outages from hazards. However, in general, such systems have proved to be somewhat less vulnerable to service outages than other utility systems. System nodes (broadcast studios, switching offices and such) are subject to flooding if located in flood-prone areas. However, because of the importance of such facilities, few are located in highly flood-prone sites. Similarly, few such facilities are likely to be located in landslide prone areas. Cellular towers in hilly areas, however, may be more subject to landslide hazards. Buried communications (copper and fiber optic) and cable television cables are usually flexible enough to accommodate several feet of ground movement before failure. Thus, while major landslides may rupture such cables, minor settlements or small slides are not nearly as likely to impact such cables as they are to break buried gas or water pipes. Above ground communications and cable television cables are subject to wind-induced failures from tree falls and pole failures. However, such failures are about ten times less common than failures of electric power lines. The better performance of communications cables arises in part because the electrical cables are always highest on the poles, thus a falling branch is usually first resisted by the power cables. Also, because the voltage levels in communications cables are much lower than those in power cables, the communication cables are not subject to ?burn down? or shorting if wind-swayed cables touch each other or get too close. Some telecommunications facilities are subject to failure as a result of loss of electric power. However, key facilities almost always have backup battery power and/or generators. Therefore, telecommunications facilities are generally much less vulnerable to outages from loss of electric power than are water or wastewater systems. Possible mitigation projects for telecommunications systems include flood proofing of important nodes, adding back-up power, relocating facilities out of active slide areas and seismic retrofits. 13-7 13.7 Electric Power Systems The electric power system is central to the functioning of a modern society. The impacts of loss of electric power are large: residential, commercial and public customers are all heavily dependent on electric power for normal functioning. Furthermore, as discussed above, other utility systems, especially water systems, are heavily dependent on electric power for normal operations. Loss of electric power, therefore, may have large impacts on affected communities, especially if outages are prolonged. Electric power for Benton County is provided by Pacific Power in Corvallis, Monroe, and North Albany and by Consumers Power in Northwest Corvallis and Vineyard Mountain, Philomath, Alsea, Blodgett-Summit, Hoskins, King Valley, and Adair Village. Electric power systems have somewhat complex operating characteristics, which are briefly summarized here. Electric power systems have three main parts: generation, transmission, and distribution. Generation is the production of electric power. Generating plans can be hydroelectric, fossil fuel (oil, gas, or coal), nuclear, or various renewable fuels (wind, solar, biomass, etc.). Most of the electric power consumed within Benton County is produced elsewhere and transmitted via high-voltage transmission lines into the county. The Bonneville Power Administration (BPA) is the primary source of power for Benton County. BPA?s power comes from hydroelectric facilities (57%) operated by the Corps of Engineers or the Bureau of Reclamation, from a nuclear plant (3%), from interchanges and wheeling (37%) of power transmitted by BPA but not owned by BPA and from other sources (3%). Through the Pacific Interties (high voltage AC or DC transmission lines) power is moved back and forth between California, the Pacific Northwest and western Canada. The transmission system is a network of high voltage lines (500 kV and 230 kV) and substations that transmit power between generation plants and the local distribution system. The distribution system is a network of lower voltage lines and substations that carries power from transmission system substations to neighborhoods and eventually to individual customers. Power outages in Benton County are most likely to result from disruption of the transmission lines carrying power from outside Benton County or within Benton County, or damage to the local distribution lines within Benton County. The generating plant system has sufficient redundancy so that failures of one or more plants do not usually lead to significant power outages. However, because of the limited generation capacity within Benton County, major disruptions in the transmission system would result in substantial curtailment of available power. A major ice storm in the Columbia River area could conceivably results in failure of most of the 500 kV transmission lines feeding Benton County from the north. 13-8 Furthermore, a severe ice storm with 2? to 4" of ice over much of Benton County could result in failure of most 500 kV and 230 kV transmission lines to and within Benton County. Such a failure, which is unlikely, but certainly not impossible (see Chapter 7), would probably entail widespread power outages in Benton County for at least 2 to 5 days. The most frequent power outages, however, are due to failure of the local subtransmission or distribution system lines. Winter storms are the most frequent cause of significant electric power outages, with wind being the primary culprit. Electric distribution lines, the low voltage lines that deliver power to neighborhoods, are the most vulnerable electric system component in winter storms. Failures most commonly result from tree falls or from ?burn downs? when wind-swayed cables touch or get too close to each other and short circuit. Distribution system failures may also be due to utility pole failures. Distribution lines may also fail due to ice loading in excess of design specifications or from landslides or debris flows or flooding which knock out utility poles. Failures of distribution system lines are thus the most common failure mode for electric power systems. Power system outages are more common and of longer duration in rural areas compared to urban or suburban areas. Rural areas are more prone to electric outages because they have a higher percentage of aboveground lines and are more likely to have hilly areas with high concentrations of trees and higher wind speeds than in flatter terrain. In rural areas, with lower population density, there is also a higher ratio of length of distribution lines per customer. With a longer length of exposed line, the probability of an outage is higher for a rural customer than for an urban customer. Once a portion of a power distribution circuit fails, all customers in that part of the circuit lose power. The duration of the power outage depends on the number of outages and the number of repair crews available for repairs. A typical power utility repair crew (2 or 3 people with a cherry picker) can restore power to a distribution circuit with common types of damage in 1 or 2 hours after arriving at the damage site. Electric transmission lines (110 kV and higher) are less vulnerable to winter storm damage because of more robust design specifications. Also, such lines are usually higher above the ground and much less prone to tree branches falling on lines. Furthermore, because of the higher voltage (compared to distribution lines), power utilities must diligently pursue tree trimming programs to avoid flashovers from lines being too close to trees. Nevertheless, transmission lines do sometimes fail due to large tree falls, rapid growth of trees near lines, unusually high winds or heavy ice loads. Benton County is subject to outages of electric power primarily due to line failures. One possible failure mode would be the transmission lines that feed Benton County from the north. More common failure modes would be failures of the trunk distribution lines within Benton County and failures of distribution circuits or service drops from distribution lines to individual buildings. The local failures are most likely due to tree falls during windstorm events. 13-9 Mitigation projects to reduce the frequency and duration of electric power systems include: augmenting tree trimming programs and hardening lines and poles in locations where ice loading or wind effects result in repeated outages. In some cases, adding connections to improve redundancy of power feed paths and adding disconnect switches to minimize areas affected by any given failure are also worthwhile. In addition to such ?hard? mitigation possibilities, there are also ?soft? or planning mitigation projects. For example, enhancing mutual aid agreements with nearby utilities can reduce the duration of major outages by increasing the number of crews and equipment for making repairs. Other planning/logistics measures such as ensuring that adequate supplies of parts and equipment are available may also reduce the duration of future outages. For Benton County, augmenting tree-trimming programs, especially for the transmission lines and the trunk distribution lines is probably the most effective mitigation measure. In selected locations upgrading lines and poles to better withstand loads from trees, wind and ice may also be appropriate. If there are key links in the systems that are highly prone to repetitive failures, undergrounding of limited portions of such links may also be appropriate. 13.8 Impacts on Benton County and Mitigation Action Items The probable impacts of disruption of transportation and utility systems on Benton County, which were summarized above, are also covered in each of the other hazard Chapters (6 -12, 14 and 5). Each of these chapters includes an impacts table that summarizes probable impacts on roads, bridges, and utility systems. A generalized summary of the probable impacts of utility disruptions and road closures on Benton Count is given in Table 13.2 below. Table 13.2 Probable Impacts of Utility Disruptions and Road Closures Inventory Probable Impacts Portion of Benton County affected Impacts may be localized for damage to local utility distribution systems or street closures, or effect the entire County for damage to transmission lines or closures of major highways to/from Benton County Buildings Negligible impacts to buildings, but loss of utilities may substantially affect function of buildings Streets within Benton County Some incidents may include temporary street closures Roads to/from Benton County Some incidents may include temporary road closures Electric power Some incidents may include temporary loss of electric power in localized parts of Benton County or for the entire County. Duration of disruptions can range from an hour to up to a probable maximum outage of 1 or 2 days. Other Utilities Some incidents may include temporary loss of utilities in localized parts of Benton County or for the entire County. Duration of disruptions can range from an hour to up to a probable maximum outage of 1 or 2 days. Casualties Low potential for direct casualties, but some incidents such as loss of electric power during cold weather may require evacuations and displacement of people (especially fragile or special needs population) to temporary shelters. 13-10 The following table contains action items for mitigation of disruptions of utility and transportation systems, from the master Action Items table in Chapter 4. See also the mitigation action items for Winter Storms (Chapter 7), which includes action items related to tree trimming efforts to reduce storm effects on the electrical distribution systems within Benton County. 13-11 13-12 Table 13.3 Mitigation Action Items for Disruption of Utility and Transportation Systems Mitigation Plan Goals Addressed Hazard Action Item Coordinating Organizations Timeline Life Safe Critical Facilities and Eme Services Protect Property Disaster Resilient Econo Public Education, Outr Partner Utility and Transportation System Disruption Mitigation Action Items Short-Term #1 Educate and encourage residents to maintain several days of emergency supplies for power outages or road closures Benton County Emergency Management Ongoing X X X Short-Term #2 Review and update emergency response plans for disruptions of utilities or roads local emergency service agencies, CRCC 1-2 Years X X X Short-Term #3 Ensure that all critical facilities in Benton County have backup power and emergency operations plans to deal with power outages Benton County Emergency Management, Benton County Facilities 1-2 Years X X X 13-13 This Page Left Blank 13-14 14.0 Hazardous Materials 14.1 Introduction For mitigation planning, hazardous materials may be defined simply as any materials that may have negative impacts on human health, animal health, or the environment. Exposure to hazardous materials may result in injury, illness, or death. The impacts of a hazardous materials exposure may be short-term with negative effects immediately or in a few seconds, minutes or hours or long-term with negative effects in days, weeks, or in some cases years after exposure. Hazardous materials vary widely in their toxicity to humans. Some hazardous materials are highly toxic so that even brief exposures to minute amounts may be dangerous or even fatal. Other hazardous materials are much less toxic and negative effects may occur only after a significant exposure to large quantities of a substance, or exposure to smaller quantities for a prolonged period of time. The technical term ?toxic,? or ?toxicity,? which is widely used to describe hazardous materials, is simply a synonym for the more common terms ?poison? or ?poisonous.? A toxic is thus defined as any substance that causes injury, illness, or death to living tissue by chemical activity. Hazardous chemicals are widely used in heavy industry, manufacturing, agriculture, mining, the oil and gas industry, high tech industries, forestry, and transportation as well as in medical facilities and commercial, public and residential buildings. There are literally hundreds of thousands of chemicals that may be hazardous to human health, at least to some extent. A typical single family home may contain dozens of potentially hazardous materials including fuels, paints, solvents, cleaning chemicals, pesticides, herbicides, medicines and others. However, for mitigation planning purposes, small quantities of slightly or moderately hazardous materials being used by end users are rarely the focus of interest. Rather, interest is focused primarily on larger quantities of hazardous materials in industrial use and on hazardous materials being transported, where the potential for accidental spills or releases is high. Situations involving extremely hazardous materials or large quantities of hazardous materials in locations where accidents may result in significant public health risk are of special concern for planning purposes. For mitigation planning purposes, the toxicity of particular hazardous materials is an important measure of the potential impact of hazardous materials on affected communities, but not the only important measure. Other characteristics of hazardous materials, especially the quantity of material and the ease of dispersal of the material may be as important as or more important than toxicity in governing the level of potential threat to a community. For example, a small quantity of a very toxic solid hazardous material used in a research laboratory may pose a much smaller level of risk for a community than a large quantity of a less toxic gaseous material in an industrial site located upwind from a populated area. 14-1 The severity of any hazardous material spill or release incident for an affected community depends on several factors, including: a) the toxicity of the hazardous material, b) the quantity of the hazardous material spilled or released, c) the dispersal characteristics of the hazardous material, d) the local conditions such as wind direction and topography, and e) the location of the spill or release in proximity to sensitive environmental areas such as a watershed that provides a community?s drinking water, and f) the efficacy of response and recovery actions. 14.2 Effects of Hazardous Materials on Humans The principal modes of human exposure to hazardous materials include: a) Inhalation of gaseous or particulate materials via the respiratory (breathing) process, b) Ingestion of hazardous materials via contaminated food or water, c) Direct contact with skin or eyes. Exposure to hazardous materials can result in a wide range of negative health effects on humans and animals. Hazardous materials are generally classified by their health effects. The most common types of hazardous materials are summarized below. Flammable materials are substances where fire is the primary threat, although explosions and chemical effects listed below may also occur. Common examples include gasoline, diesel fuel, and propane. Explosives are materials where explosion is the primary threat, although fires and chemical effects listed below may also occur. Common examples include dynamite and other explosives used in construction or demolition. Irritants are substances that cause inflammation or chemical burns of the eyes, nose, throat, lungs, skin or other tissues of the body in which they come in contact. Examples of irritants are strong acids such as sulfuric or nitric acid. Asphyxiants are substances that interfere with breathing. Simple asphyxiants cause injury or death by displacing the oxygen necessary for life. Nitrogen is a good example. Nitrogen is a normally harmless gas that constitutes about 78% of the atmosphere. However, nitrogen releases in a confined space may result in asphyxiation by displacing oxygen. Chemical asphyxiants are substances that prevent the body from using oxygen or otherwise interfere with the breathing process. Common examples are carbon monoxide and cyanides. Anesthetics and Narcotics are substances with act on the body by depressing the central nervous system. Symptoms include drowsiness, weakness, fatigue, 14-2 and in coordination, which may lead to unconsciousness, paralysis of the respiratory system and death. Examples include numerous hydrocarbon and organic compounds. Hazardous materials may also have a wide variety of more specialized impacts on human health. Other types of toxic effects are briefly summarized in Table 14.1. Table 14.1 Other Types of Hazardous Materials Type of Hazardous Material Effects on Humans Hepatotoxin Liver damage Nephrotoxin Kidney damage Neurotoxin Neurological (nerve) damage Carcinogen May result in cancer Mutagen May produce changes in the genetic material of cells Teratogen May have adverse affects on sperm, ova, or fetal tissue Radioactive materials May result directly in radiation sickness at high exposure levels or act as carcinogen, mutagen, or teratogen Infectious substances Biological materials such as bacteria or viruses that may cause illness or death Much of the information above was summarized from Chapter Six of the Handbook of Chemical Hazard Analysis Procedures1. The first few chapters of this handbook contain a concise summary of many of the technical aspects of hazardous materials. These chapters may be useful to readers seeking a more technical introduction to the nomenclature and science of hazardous materials. 14.3 Classification System and Emergency Response Protocols A standardized system is used to classify and identify hazardous materials. The 2004 Emergency Response Guidebook (A Guidebook for First Responders During the Initial Phase of a Dangerous Goods/Hazardous Material Incident)2 outlines the classification system. The 2004 Emergency Response Guidebook is an extremely useful reference book that provides standardized first response protocols and detailed reference sheets for the most common classes of hazardous materials. Hazardous material releases are predominantly accidental results of traffic accidents, equipment failures or human errors. In rare cases, hazardous material releases may result from deliberate actions of sabotage or terrorism. 14-3 First responders for hazardous material incidents are generally public safety personnel (police or fire). The standard protocols for first responders are briefly summarized below, following guidance in the 2004 Emergency Response Guidebook. The primary guidance for first responders is to: a) resist rushing in, b) approach the incident site from upwind, uphill or upstream, and c) stay clear of all spills, vapors, fumes and smoke. Upon approaching the incident site, a three-step procedure is recommended: a) identify the material, b) find the materials three digit guide number, and c) read the numbered guide carefully and respond accordingly. Identification of hazardous materials is by finding any one of the following: a) the four-digit ID number on a placard or orange panel, b) the four-digit ID number on a shipping document or package, or c) the name of the material on a placard, shipping document or package. Once identified by ID number or name, the material?s three-digit guide number is looked up in either the ID number index or the name index. Then, the procedures and precautions outlined in the guide for the identified class of material are carefully followed. For each class of material, the guides have critical information on potential hazards, suggested evacuation distances for small and large spills, and recommended emergency response actions, including first aid. For further technical details see the 2004 Emergency Response Guidebook. In Oregon, the Office of State Fire Marshal has defined standard response protocols for hazardous materials incidents in a series of Standard Operating Guidelines3. This series of about a dozen standard operating guidelines covers every main aspect of emergency response and recovery, including decisions to respond, levels of response, general response guidelines, mitigation methods, decontamination procedures, personal protective equipment, and others. In Oregon, there is a three-level response plan for hazardous material incidents involving first responders and specialized emergency response teams. First responders are local staff, generally public safety staff (police and fire) that are trained in basic procedures for the initial (first) response to hazardous materials incidents. The responsibilities of first responders including securing the incident scene and making a preliminary assessment of the potential severity of the hazardous material incident and the level of threat, if any, to persons at and outside of the immediate incident area. In Benton County, most fire service first responders are trained to either the ?Awareness? Level or ?Operations? Level. 14-4 Emergency response teams are specialized teams, composed primarily of public safety staff, and with higher-level training and more specialized equipment for dealing with hazardous materials incidents than first responders. State of Oregon Hazardous Materials Team members are trained to the ?Technician? Level or higher. Statewide, these emergency response teams respond to about 350 hazardous material incidents per year, or about one per day, on average (Standard Operating Guidelines, Team Background3). In Oregon, there are fourteen emergency response teams, generally with 18 members each. Each response team has a defined geographic area of primary responsibility. For Benton County, the Hazardous Materials Response Team with primary responsibility is the HM05 Linn/Benton Team that covers Benton, Linn, Lincoln, Polk, and Marion Counties The three-level response plan for hazardous materials incidents is characterized as Level I Response, Level II Response and Level III response. The distinction between Level I, II, and III responses depends on: a) class of hazardous material b) size of container c) fire/explosion potential d) leak severity and container integrity, and e) threat to life safety. Level I Responses are those incidents readily controlled or stabilized by first responders. The HAZMAT Emergency Response Team personnel may provide technical assistance via telephone or on-site assistance, but full response by an Emergency Response Team is not required. Level II Responses are those incidents that require response from a HAZMAT Emergency Response Team for control or stabilization of the spill. The Emergency Response Team response level may be 2-4 personnel for identification of the material and guidance on appropriate response actions or the response level may be a small team response of 6-8 personnel. Level III Responses are those incidents that require special resources, including one or more full Emergency Response Teams and possibly other outside agencies for support. Further technical details of the Level I, II, and III responses are given in the State of Oregon Standard Operating Guidelines, Levels of Response to Hazardous Materials Incidents, T-003.3 A very useful glossary of technical terms used for hazardous materials incidents is given in the State SOG Glossary of Terms (Standard Operating Guidelines, Glossary of Terms, SOG-T-002.3) 14-5 14.4 Statutory and Regulatory Context The manufacture, storage, use, transportation, and disposal of hazardous materials are subject to a myriad of federal, state, and local regulations. In the context of mitigation planning and emergency response, we focus on reporting requirements for chemicals subject to mandatory risk management planning and extremely hazardous substances subject to additional reporting and planning requirements. Oregon statutes governing hazardous materials are included in the following sections of the Oregon Revised Statutes: ORS Chapter 453, 453.001 to 453.185 and 453.605 to 453.807 ORS Chapter 465, Hazardous Waste, Haz. Mat. I ORS Chapter 466, Hazardous Waste, Haz. Mat. II ORS Chapter 475, 475.405 to 475.495, Illegal Drug Clean-up ORS Chapter 480, Explosives, flammable materials, pressure vessels. Section 112(r) of the Clean Air Act Amendments was designed to prevent accidental releases of hazardous substances. The rule establishes a list of chemicals and threshold quantities that identify facilities subject to subsequent accident prevention regulations. The listed substances have the greatest potential to pose the greatest hazard to public health and the environment in the event of an accidental release. The full list of Section 112(r) chemicals, including planning threshold quantities (TPQ) is given in the Office of State Fire Marshal?s Hazardous Substance Information System database (available on CD from OSFM). Hazardous materials may be released to the environment either routinely during manufacturing and other ongoing processes or accidentally. Certain types of businesses are required to report such releases annually for a specified list of chemicals. The paragraph below, quoted from the Office of State Fire Marshal, Hazardous Substance Information System (HSIS)4, summarizes the intent and content of the regulatory requirements for substances covered under the Toxic Release Inventory regulations. ?The Toxics Release Inventory (TRI) Program was established by section 113 of the Emergency Planning and Community Right to Know Act (EPCRA) of 1986. Under this program certain businesses are required to submit reports each year on the amounts of toxic chemicals their facilities release into the environment, either routinely or as a result of accidents.? There are additional reporting and planning requirements for materials deemed to be extremely hazardous. The paragraphs below, quoted from the Office of State Fire Marshal, Hazardous Substance Information System (HSIS)4, summarize the intent and content of the regulatory requirements for extremely hazardous materials. 14-6 ?SARA Title III, section 302 requires owners and operators to notify the State Emergency Response Commission (SERC) regarding the presence of Extremely Hazardous Substances (EHS) at their facilities. Section 303 requires facilities that possess a threshold planning quantity (TPQ) of an EHS to develop a contingency plan in case of an accidental release, and assist emergency planners and emergency response organizations in developing a plan to protect the community from possible injury from a release of dangerous chemicals.? The full list of substances designated as Extremely Hazardous Substances (EHS) is given in the Office of State Fire Marshal?s Hazardous Substance Information System database (available on CD from OSFM). 14.5 Fixed Site Hazardous Materials Locations in Benton County Hazardous materials at fixed sites are generally identified by a NFPA (National Fire Protection Association) placard, commonly referred to as the NFPA hazard diamond. These hazard placards contain standardized information on the fire hazards and health hazards of the hazardous materials. Technical details about these hazard placards are given in the publication NFPA 704: Standard for the Identification of the Fire Hazards of Materials for Emergency Response (1996). The Oregon Office of State Fire Marshal maintains a comprehensive listing of hazardous materials locations in Oregon4. Key data for Benton County are shown below in Table 14.2. Table 14.2 Summary of Hazardous Substance Information System (HSIS) Data County Total Reports Reportable Quantities 112(r) 1 Chemicals 313 (TRI)2 Chemicals EHS3 Chemicals Benton 942 409 222 93 17 1 Chemicals reportable under Section 112(r) 2 Chemicals reportable under Section 313, Toxics Release Inventory 3 Extremely hazardous substances For Benton County, the HSIS database has hazardous materials reports for 942 companies and other entities such as cities that have hazardous materials. Of these reporting locations, 409 or about 44%, have reportable quantities of hazardous materials. As shown in Table 14.2, Benton County also has 222 sites with Section 112(r) chemicals, 93 sites with Section 313 Toxics Release Inventory chemicals, and 17 sites with Extremely Hazardous Substances. For mitigation planning purposes, Extremely Hazardous Substances are of special concern. 14-7 More detailed information about hazardous materials can be found online in the State Fire Marshal?s Community Right-to-Know (CR2K) Hazardous Substance Information Program. Members of the public have the responsibility for informing themselves, getting involved with the planning and emergency response exercises and knowing the potential risks. Hazardous Substance Information System (HSIS) The Hazardous Substance Information System identifies hazardous substances that are used, stored, manufactured and/or disposed of at business sites in Oregon. The Office of State Fire Marshal (OSFM) annually surveys businesses and requires them to provide demographic information and report hazardous substances at or above reportable quantities. Businesses possessing reportable quantities of hazardous substances are required to report specific information including the chemical name, maximum amount and storage location. These businesses are also required to notify the OSFM within 30 days of any substantive changes that occur at the facility. Environmental Protection Agency Tier II Chemical Inventory Reporting By submitting the Office of State Fire Marshal Hazardous Substance Information Survey, Oregon businesses are complying with the EPA Tier II Chemical Inventory reporting requirements. To comply with Oregon reporting requirements, businesses must submit their chemical inventory information on a Hazardous Substance Information Survey. Tier II forms are not accepted. How to Access the Hazardous Substance Information Database The Office of State Fire Marshal's Hazardous Substance Information database is available online at http://www.sfm.state.or.us/CR2K/cr2k.htm. Scroll down to the ?Community Right To Know? and click on the desired item. It is then possible to establish information parameters and run queries of our database and obtain the information. The database will be searched and the information will be displayed on the user?s computer, and then either print or save the data to their system. Limited Access Notification Due to potential security issues, information on hazardous substances that have hazard classes listed in Table 14.3 below is not provided by individual facility. This information can be requested by contacting the Office of State Fire Marshal?s, Community Right to Know Unit at SFM.CR2K@state.or.us. 14-8 Table 14.3 Limited Access Materials Class Description Class Description 1.1 Class A Explosives 1.5 Insensitive Explosives 1.2 Class B Explosives 2.3 Poison Gases 1.3 Class C Explosives 6.2 Etiologic Materials1 1.4 Blasting Agents 7.3 Radioactive Materials 1 Etiologic means disease causing 14.6 Commentary on Inventory of Extremely Hazardous Substances (EHS) There are 17 sites in Benton County with reportable quantities of extremely hazardous substances (EHS). Data on the geographic distribution within Benton County of EHS sites and other reportable chemicals are summarized below in Table 14.4 Table 14.4 Geographic Distribution of Extremely Hazardous Substances (EHS) and Other Reportable Chemical Sites in Benton County Community Total Reports 112(r) 1 Chemicals 313 (TRI)2 Chemicals EHS3 Chemicals Corvallis 708 169 80 17 Philometh 140 38 10 0 Monroe 48 12 0 0 Albany 11 1 2 0 Alsea 12 6 1 0 Blodgett 12 2 0 0 Other 11 2 0 0 Total 942 230 93 17 1 Chemicals reportable under Section 112(r) 2 Chemicals reportable under Section 313, Toxics Release Inventory 3 Extremely hazardous substances As noted above in Section 14.1, the toxicity of particular hazardous materials is an important measure of the potential impact of hazardous materials on affected communities, but not the only important measure. Other characteristics of hazardous materials, especially the quantity of material and the ease of dispersal of the material may be as important, or more important, in governing the level of potential threat to a community. A full review of the potential public health impacts of accidents or deliberate acts at each of the above 17 sites is beyond the scope of this mitigation plan. 14-9 14.7 Benton County Locations with Large Quantities of Hazardous Materials Benton County Emergency Management selected the following four sites in Benton County as being of special concern for hazardous materials because of large quantities of hazardous materials typically at these sites or other reasons. These sites are listed as examples only and listing should not be interpreted pejoratively. 14.7.1 Hewlett Packard, Corvallis The Hewlett Packard facility, located at 1000 NE Circle Blvd, Corvallis, which manufactures semiconductor components and computer peripheral equipment, employs about 4400 people. The State Fire Marshal?s Hazardous Substance Information System (HSIS) reports for this facility list a total of 96 different chemicals at this facility, filtered to eliminate chemicals in the categories shown above in Table 14.3. These 96 different chemicals contain a wide range of ingredients as the most hazardous component. However, most of these chemicals are present in small quantities. Seven of the chemicals at this site are included on the Benton County list of Extremely Hazardous Substances (EHS). These EHS are listed below in Table 14.5. Table 14.5 Extremely Hazardous Substances at the Hewlett Packard Facility, Corvallis Chemical Trade Name Most Hazardous Component Form Maximum Quantity Units Hazard Type Protect Distance (km)1 Ammonia, anhydrous Ammonia gas 20 - 49 gallon s corrosive, acute health hazard 1.1 Boron trichloride2 Boron trichloride gas n/a cubic feet corrosive, poisonous gas 1.6 Chlorine2 Chlorine gas n/a gallon s poisonous gas 6.8 Hydrochloric acid Hydrochloric acid liquid 1,000 ? 4,999 gallon s corrosive, acute health hazard 4.3 Hydrofluoric acid Hydrofluoric acid liquid 200 ? 499 gallon s corrosive, acute health hazard 2.9 Sulfuric acid 10 to 50% Sulfuric acid liquid 1,000 ? 4,999 gallon s corrosive, acute health hazard 5.6 Sulfuric acid Sulfuric acid liquid 1,000 ? 4,999 gallon s corrosive, reactive material acute health hazard 5.6 14-10 1 Protect distance (km) is for nighttime large spills. Distances for small spills and for daytime spills are given in Table 14.11. 2 Chemicals listed in the 2000 version of HSIS but excluded from the 2004 version of HSIS. For each of these hazardous materials, Table 14.11 in Section 14.8 has important reference and response information, including references to the appropriate emergency response Guide Number, initial isolation distances, protection distances downwind (day and night) for both small and large spills (2004 Emergency Response Guidebook). This facility has an emergency plan and procedures in place under the auspices of the EHS Office in Building 4. Potential community impacts are moderate for this facility. Spills of any of the EHS listed above in Table 14.5, or spills of other chemicals at this site, might result in a hazardous plume downwind. However, most of the quantities at this facility are relatively small and, therefore, the potential for a major hazardous materials incident is relatively low. 14.7.2 Oregon State University Nuclear Reactor, Corvallis In the United States, nuclear reactors have been operating since the 1940s, with a generally excellent overall safety record. Nevertheless, because of a general fear of radiation, and the possibility of significant accidents such as that at the Three Mile Island power plant in Pennsylvania or a major accident such as that at Chernobyl in the former Soviet Union, the safety of nuclear reactors certainly warrants evaluation. The OSU research reactor, operating by the Department of Nuclear Engineering, is much smaller than reactors used for commercial production of electric power. The OSU reactor is licensed by the NRC to operate at a maximum sustained power of 1.1 megawatts (1100 kilowatts) or about 1000 times less than the power levels typical in commercial power reactors. The OSU reactor is a TRIGA Mk. II reactor manufactured by the General Atomics Company. General information about the OSU reactor is given on the OSU Radiation Center website (www.ne.orst.edu/facilities/radiation/ostr.html). The reactor is a water- cooled swimming pool type reactor that uses uranium/zirconium hydride fuel elements in a circular grid array. The reactor core is surround by a ring of graphite that serves to reflect neutrons back into the core. The core is situated near the bottom of a 22 feet deep water-filled tank, and the tank is surrounded by a concrete monolith that acts as a radiation shield and also provides structural support for the tank. Commercial power reactors in the United States are of two basic design types: pressurized water systems and boiling water systems. Operational safety for either design type is provided by robust design and testing of components, by multiply 14-11 redundant backup safety systems, and by massive containment buildings around reactors. However, both these types of reactors rely on active safety control systems. In the event of failures of the primary reactor control mechanisms, active systems involving electric power, pumps, cooling water etc. are triggered to control the nuclear core and prevent ?runaway? reactions that could lead, in the worst-case scenario, to major accidents with substantial release of radiation. The OSU reactor is a completely different design than designs used by commercial power reactors. For the OSU reactor, operational safety is inherent to the design and achieved passively, rather than relying on external, active controls. If normal control of the OSU reactor is lost, for any reason, the reactor reduces power within a few thousands of a second. This almost instantaneous passive control is achieved by the fuel rod design. If the normal graphite control rods are removed, the fuel rods begin to warm due to the ongoing nuclear decay in the fuel. However, for the OSU reactor design this warming immediately results in lower nuclear activity and a consequent decrease in operating power. This self-regulating, passive control system thus does not depend on any external system to prevent runaway reactions. In other words, the fuel rod system is inherently stable with runaway heating being physically impossible. In total, the small reactor size, the inherently stable passive safety design, and the concrete containment structure provide an extraordinarily high level of operational safety for the OSU reactor. The possibility of significant radiation leakage due to accidents is thus essentially zero. However, especially in the post September 11th environment, the possibility of deliberate terrorist actions aimed at the OSU reactor, while remote, cannot be categorically excluded. A large conventional explosive device detonated near the reactor core could, in effect, produce a ?dirty bomb? or ?radiological? bomb. A ?dirty? or ?radiological? bomb is a device that uses conventional explosives to disperse radioactive materials. Although there is absolutely no possibility of a nuclear explosion, a ?dirty? bomb event could locally disperse radiation with resulting significant public health and severe decontamination problems. In light of this possibility, however remote, a review of the physical and operational security of the OSU reactor site is warranted to determine whether or not additional security measures may be appropriate. For the OSU reactor, separate from the operational safety issues (which are minimal) and the potential terrorist threat (which is remote, but cannot be categorically denied), there are also small quantities of hazardous materials on site. The reports in the Office of State Fire Marshal?s Hazardous Substance Information System (HSIS) lists three materials present at the OSU reactor: compressed gas cylinders with argon and oxygen, and small quantities (less than 5,000 millicuries) of solid radioactive isotopes. Per se, none of these materials pose a significant public health risk. However, the small quantities of radioactive isotopes are of potential terrorist interest for making ?dirty? bombs. In this context, a review of the physical and operational security for these radioactive isotopes is warranted to determine whether or not additional security measures may be appropriate. 14-12 The OSU reactor has a formal emergency operations plan, outlined in a procedures book, and last updated in 2005. Potential community impacts are low for this facility. The possibility of a reactor core accident is negligible, due to the passive safety design of the reactor itself. There are only small quantities of a few hazardous materials at this site. However, the possibility, however, remote, of deliberate terrorist actions cannot be disregarded for this facility and appropriate security measures and emergency planning are recommended. 14.7.3 Western Pulp Products, Corvallis The Western Pulp Products facility, located at 5005 SW Lowe St., Corvallis, which manufactures molded pulp products and converted paper products, employs about 65 people. The State Fire Marshal?s Hazardous Substance Information System (HSIS) reports for this facility list a total of 33 different chemicals at this facility, filtered to eliminate chemicals in the categories shown above in Table 14.3. These 33 different chemicals contain a wide range of ingredients as the most hazardous component. However, most of these chemicals are present in small quantities. The company data sheet in the Office of State Fire Marshal?s Hazardous Substances Information System (HSIS) indicates that none of the chemicals at this site are included on the list of Extremely Hazardous Substances (EHS). However, the individual chemical data sheets include sulfuric acid, which is on the EHS list and a chemical with trade name Afranil SLO, which is stated to contain formaldehyde as its most hazardous ingredient. Formaldehyde is also on the EHS list. The chemical inventory data for this site also includes fairly large quantities of a chemical with trade name Amres Pr-475 S Wet Strength, which is stated to contain 1,3-dichlor-2-propanol as its most hazardous component. These chemicals are listed below in Table 14.6. Table 14.6 Extremely Hazardous Substances and Other Chemicals at the Western Pulp Products Facility, Corvallis Chemical Trade Name Most Hazardous Component Form Maximum Quantity Units Hazard Type Protect Distanc e (km)1 Afranil SLO Formaldehyde liquid 1,000 ? 4,999 poun ds flammable liquid - corrosive N/A2 Amres Pr-475 S Wet Strength 1,3-dichloro- propanol liquid 10,000 ? 49,999 poun ds substances ? toxic and/or corrosive (combustible) N/A2 Sulfuric acid Sulfuric acid liquid 500 ? 999 poun ds corrosive, reactive material acute health hazard 5.6 14-13 1 Protect distance (km) is for nighttime large spills. Distances for small spills and for daytime spills are given in Table 14.11. 2 N/A indicates that protection distances are not given in the 2004 Emergency Response Guidebook. For these hazardous materials, Table 14.11 in Section 14.8 has important reference and response information, including references to the appropriate emergency response Guide Number, initial isolation distances, protection distances downwind (day and night) for both small and large spills (2004 Emergency Response Guidebook). For materials without specific, initial isolation distances, protection distances downwind (day and night) for small and large spills, the generic public safety guidance is an immediate isolation distance of 25 to 50 meters from a spill site. The Office of State Fire Marshal?s Hazardous Material Information System (HSIS) database does not indicate that this facility emergency procedures/plans in place. Potential community impacts are moderate for this facility, which has only one EHS, sulfuric acid. Spills of any of the materials listed above in Table 14.6, or spills of other chemicals at this site, might result in a hazardous plume downwind. However, most of the quantities at this facility are relatively small and, therefore, the potential for a major hazardous materials incident is relatively low. 14.7.4 Wilbur Ellis Co., Monroe The Wilbur Ellis Co. facility, located at 555 Depot St., Monroe, which provides agricultural chemicals and fertilizer products, employs about 6 people. The State Fire Marshal?s Hazardous Substance Information System (HSIS) reports for this facility list a total of 85 different chemicals at this facility, filtered to eliminate chemicals in the categories shown above in Table 14.3. These 85 different chemicals contain a wide range of ingredients as the most hazardous component. However, most of these chemicals are present in small quantities. The company data sheet in the Office of State Fire Marshal?s Hazardous Substances Information System (HSIS) indicates that four of the chemicals at this site are included on the Benton County list of Extremely Hazardous Substances (EHS). These EHS chemicals are listed below in Table 14.7 14-14 Table 14.7 Extremely Hazardous Substances at the Wilbur Ellis Co Facility, Monroe Chemical Trade Name Most Hazardous Component Form Maximum Quantity Units Hazard Type Protect Distanc e (km)1 Endosulfan Endosulfan solid 200 ? 499 poun ds substances ? toxic (non- combustible) N/A2 Aldicarb3 0?S-dimethyl acetylphosphor amidothioate solid n/a poun ds substances ? toxic (non- combustible) N/A2 Paraquat3 1,1-dimethyl-bi- pyridiniuim liquidn/a gallon s substances ? toxic (non- combustible) N/A2 Ethroprop3 Ethroprop liquidn/a gallon s substances ? toxic (non- combustible) N/A2 1 Protect distance (km) is for nighttime large spills. Distances for small spills and for daytime spills are given in Table 14.11. 2 N/A indicates that protection distances are not give in the 2004 Emergency Response Guidebook. 3 Chemicals listed in the 2000 version of HSIS but excluded from the 2004 version of HSIS. None of these hazardous materials have specific, initial isolation distances, protection distances downwind (day and night) for small and large spills (2004 Emergency Response Guidebook). The generic public safety guidance is an immediate isolation distance of 25 to 50 meters from a spill site. The Office of State Fire Marshal?s Hazardous Material Information System (HSIS) database indicates that this facility has emergency procedures/plans in place, with plans etc. located at the plant office. In addition to the above EHS materials, this facility also sometimes has large quantities of ammonium nitrate fertilizer. This material is not particularly toxic, but is of potential terrorist interest as an ingredient for explosives. In this context, a review of the physical and operational security for this material is warranted to determine whether or not additional security measures may be appropriate. Potential community impacts are moderate for this facility. Spills of any of the EHS listed above in Table 14.7, or spills of other chemicals at this site, might result in a hazardous plume downwind. However, most of the quantities at this facility are relatively 14-15 small, these hazardous materials are not especially prone to dispersion, and, therefore, the potential for a major hazardous materials incident is relatively low. 14.8 Hazardous Materials Transport: Truck Shipments, Rail Shipments and Pipelines 14.8.1 Overview and Truck Shipments Hazardous materials may be transported once or many times during their ?life cycle? of raw materials, manufacturing, incorporation in other products, wholesale and retail trade, use, waste disposal, and recycling. The transport of hazardous materials may be local within a single city or across a state, across the country or internationally. For Benton County, a general perspective on hazardous materials incidents is provided by annual statistics of hazardous materials incidents5, prepared by the Office of State Fire Marshal. These incident reports include all reported hazardous material incidents, at fixed sites and during transportation, except generally excluding: a) motor fuels which are spilled in quantities less than 42 gallons, b) sewage overflows, c) structure fires or other emergencies where hazardous substances are involved as exposures, if the quantities exposed are less than 42 gallons. Statewide incident data for 2002-2003 are summarized in Table 14.8 below from the OSFM Annual Incident Reports. For these four years, statewide incidents have ranged from 399 to 248 per year. Of the total HAZMAT incidents, an average of about 31% occurred on public roads in Oregon. The decreasing trend over these four years may reflect improved safety, or changes in reporting, or may just be a statistical fluctuation. Over this four year period there were a total of 1284 reported HAZMAT incidents, of which only 10 were in Benton County (about 0.8% of the statewide total incidents). Incident data for Benton County are shown below in Table 14.9. Table 14.8 Hazmat Incidents Reported Statewide in Oregon Year Hazmat Incidents1 Percent on Roads 2000 399 35.09% 2001 377 29.71% 2002 260 27.69% 2003 248 31.85% average 321 31.39% 1 reported incidents as per OSFM annual incident reports 14-16 Table 14.9 Hazmat Incidents Reported in Benton County Year Hazmat Incidents1 2000 12 2001 7 2002 2 2003 4 average 6.25 1 reported incidents as per OSFM annual incident reports Diesel (1), mineral acid (1) Diesel (1), natural gas (1) Most Common Chemicals Involved Fuels (4), propane (2) Fuels (3), drug lab chemicals (2) Most of the reported HAZMAT incidents in Oregon involve a relatively small number of hazardous materials, as shown below in Table 14.10. These statewide data present a very useful overview of hazardous material incidents in Oregon. For Benton County, the general pattern of hazardous materials is likely to be similar to the statewide pattern below. Most hazardous materials incidents in Benton County are likely to be the most commonly involved materials as shown below (i.e., drug lab chemicals, fuels, and motor vehicle fluids). Table 14.10 Hazardous Materials Incidents in 2000-20035 Reported Categories of Hazardous Materials Chemical 2000 2001 2002 2003 Total Percent Drug lab chemicals 66 50 20 35 171 13.32% Diesel, gasoline, fuel oil 99 73 43 45 260 20.25% Antifreeze, motor oil, hydraulic fluid, transmission fluid 29 16 8 6 59 4.60% Natural gas 45 35 19 14 113 8.80% Propane 14 7 10 4 35 2.73% Unknown chemical 44 55 36 20 155 12.07% No chemical involved 10 26 15 27 78 6.07% Other chemicals 92 115 109 97 413 32.17% Total 399 377 260 248 1284 100.00% Number of Incidents The low number of HAZMAT incidents for Benton County reflects the relatively low population of the county (corresponding to fewer shipments of fuels and other hazardous commodities relative to more populated county). Another contributing factor may be the fact that there are no major interstate highways or major through roads between major population centers passing through Benton County. For Benton County, the most likely road/highway HAZMAT incidents involve the common chemicals shown above in Table 14.10. In addition, chemicals necessary for 14-17 the forest products and fertilizer industry facilities in the county may also be involved in HAZMAT incidents, along with outgoing shipments of fertilizer products. 14.8.2 Rail Shipments There are 22 freight railroads currently operating in Oregon, according to 2004 data from the Oregon Department of Transportation website (www.odot.state.or). Addresses and contact information for all of these railroads are given on the above referenced website, as are website addresses for several of the larger railroads. However, there are no freight railroads serving Benton County. Thus, the only potential for rail HAZMAT incidents would be from nearby rail lines in Linn County (e.g., Albany). 14.8.3 Pipelines There only major fuel pipeline systems in Benton County are the natural gas transmission and distribution systems in the larger cities, operated by Northwest Natural Gas. There are no interstate or long-distance major fuel pipelines passing through Benton County. The United States Department of Transportation Office of Pipeline Safety regulates interstate pipelines. USDOT imposes a broad range of standards and inspection requirements for pipeline design, material specifications, construction standards, maintenance and testing requirements. For the United States as a whole, a network of about 300,000 miles of natural gas transmission lines serve about 1.5 million miles of distribution system lines which serve about 160 million customers. Overall, the safety record of natural gas transmission pipelines is good with relatively few significant accidents. The natural gas distribution system in Benton County includes the cities of Corvallis, north Albany, Monroe and Philomath. The natural gas pipeline systems of local gas utilities, including the systems in Benton County, almost always follow road and street patterns because of established utility rights of way and because of the need to connect with each building served. Thus, for areas served by natural gas, the local street network is essentially identical to the natural gas distribution pipe network. Overall, the safety record of natural gas distribution pipelines is good with relatively few significant accidents. Natural gas is not toxic (i.e., not poisonous). However, natural gas can be an asphyxiant if it displaces oxygen in an enclosed space. Natural gas burns readily when ignited, but only when gas concentrations are between 4% and 15% in air. In its pure state, natural gas is both colorless and odorless. The strong odor normally associated with natural gas is an odorant deliberately introduced at low concentrations to serve as a warning of the presence of natural gas. The strong odorant is generally added to natural gas at the local distribution level, by local gas utilities, and is readily detectible in concentrations well below the explosive range. 14-18 Fires and/or explosions from natural gas leaks in pipelines are rare. In part, the rarity of fires and/or explosions is due to the fact that natural gas is about 1/3rd less dense than ordinary air. Thus, leaking natural gas does not accumulate near the ground or ?pond? in low-lying areas (as heavier gases such as liquefied natural gas or gasoline fumes may do). Instead, leaking natural gas rises rapidly and is dissipated by dilution in the atmosphere. The fires and /or explosions that do occur from natural gas leaks are generally in buildings where the confined space allows leaking gas to accumulate until ignited. Between 2000 and 2003 annual statistics of hazardous materials incidents5, prepared by the Office of State Fire Marshal, show a total of only 113 natural gas incidents statewide in Oregon. Most of these incidents were minor without casualties or significant damage. Pipeline breaks due to natural causes may occur due to landslides or earthquakes. Earthquake induced pipe breaks for natural gas transmission lines are most likely to occur in areas of soft soils subject to liquefaction and/or lateral spreading which cause significant pipe displacements. The most likely locations for such breaks during an earthquake are on slopes of soft ground near where pipelines cross rivers or streams. The most common man-made cause of pipeline breaks is pipeline rupture due to pipes breaking when heavy construction equipment is used to excavate for construction projects. Most such breaks occur in local distribution lines. Pipeline breaks can also be caused by deliberate actions of sabotage or terrorism. Although pipelines are not symbolic targets with political, historical, and cultural significance, they are potential targets for terrorist actions. Major pipeline breaks could disrupt gas service over wide areas with resulting significant economic impacts. Natural gas utilities and local emergency responders are generally well prepared to deal with natural gas breaks, because such incidents occur frequently enough to have well- standardized response procedures. Evacuations for natural gas distribution system pipeline ruptures are generally limited to the immediate area of the break. 14.9 Reference Information for Hazardous Materials Incidents Emergency Response This section provides references to the appropriate Guide Number in the 2004 Emergency Response Guidebook, along with the corresponding initial isolation distances and protective action distances for a few common industrial chemicals. Initial isolation distances are given for both large and small spills. Protective action distances are given for both small and large spills and for day and night conditions. See Table 14.11 below; all of this information is from the 2004 Emergency Response Guidebook. As per the 2004 Emergency Response Guidebook, small spills are defined as one that involves a single small package (e.g., a drum containing up to approximately 200 liters), a small cylinder or a small leak from a large package. A large spill is one that involves a spill from a large package or multiple spills from many small packages. For 14-19 14-20 very large spills, that involve more than one tank car, cargo tank, portable tank or large cylinder, the large spill distances may need to be increased. As per the 2004 Emergency Response Guidebook, protective distances are defined in the downwind direction from the spill site. The width of the protective distance is equal to 50% of the downwind protect distance on each side of the wind direction. In other words, the total protect area is a square with sides equal to the defined protect distance. See Figure 14.11 below from the 2004 Emergency Response Guidebook. 14-21 Table 14.11 Extremely Hazardous Substances: Reference Data from 2004 Emergency Response Guide Small Spills Large Spills Most Hazardous Ingredient Guide Number Guide Category Isolation Distance (m) Day Protect Distance (km) Night Protect Distance (km) Isolation Distance(m) Day Protect Distance (km) Night Protect Distance (km) Ammonia 125 Gases - corrosive 30 0.2 0.2 60 0.5 1.1 Chlorine 124 Gases ? toxic and/or corrosive - oxidizing 30 0.3 1.1 275 2.7 6.8 Hydrochloric acid 1 157 Substances ? toxic and/or corrosive (non-combustible/water-sensitive) 30 0.2 0.6 185 1.6 4.3 Hydrofluoric acid ` 157 Substances ? toxic and/or corrosive (non-combustible/water-sensitive) 30 0.2 0.6 125 1.1 2.9 Sulfur dioxide 125 Gases ? corrosive 30 0.3 1.1 185 3.1 7.2 Sulfuric acid 137 Substances ? water reactive - corrosive 60 0.3 1.1 305 2.1 5.6 1 For hydrochloric acid and hydrofluoric acid, the isolation and protect distances are for hydrogen chloride anhydrous and hydrogen fluoride anhydrous, respectively, because the 2004 ERG did not have specific listing for these acids. Figure 14.12 Initial Isolation Zone and Protective Action Zones for Hazardous Material Spills See the 2004 Emergency Response Guide section on Introduction to the Table of Initial Isolation and Protective Action Distances (Page 311) for factors that may increase or decrease Protective Action Distances The 2004 Emergency Response Guidebook has excellent general guidance on the decision factors that govern protective actions appropriate for a given incident. This guidance is given below verbatim. The protective action distances given above in Table 14.11 are for general guidance only. For each specific hazardous material incident, the local jurisdiction Incident Commander, in consultation with the HAZMAT Response Team Branch Leader, makes incident specific decisions based on the specific conditions of each incident. PROTECTIVE ACTION DECISION FACTORS TO CONSIDER ?The choice of protective actions for a given situation depends on a number of factors. For some cases, evacuation may be the best option; in others, sheltering in-place may be the best course. Sometimes, these two actions may be used in combination. In any emergency, officials need to quickly give the public instructions. The public will need continuing information and instructions while being evacuated or sheltered-in-place. Proper evaluation of the factors below will determine the effectiveness of evacuation or in-place protection. The importance of these factors can vary with emergency conditions. In specific emergencies, other factors may need to be identified and considered as well. This list indicates what type of information may be needed to make the initial decision. 14-22 14-23 The Dangerous Goods ? Degree of health hazard ? Amount involved ? Containment/control of release ? Rate of vapor movement The Population Threatened ? Location ? Number of people ? Time available to evacuate or shelter in-place ? Ability to control evacuation or shelter in-place ? Building types and availability ? Special institutions or population, e.g., nursing homes, hospitals, prisons Weather Conditions ? Effect on vapor and cloud movement ? Potential for change ? Effect on evacuation or shelter-in-place? Evacuate means to move all people within the protective distance area to a safer place. To evacuate, there must be enough time for people to be warned, to get ready, and to leave the area. If there is enough time, evacuation is usually the best protective action. Evacuations are usually progressive with the first evacuees being people closest to the incident location. Shelter in-place means that people within the protective distance area are advised to seek shelter inside a building and remain inside until the danger passes. Sheltering in- place is used when evacuation would cause greater risk than staying put, or when an evacuation cannot be performed. For shelter in-place, occupants are advised to close all doors and windows and to shut off all ventilating, heating and cooling systems. Shelter in-place may not be appropriate if: a) vapors are flammable, b) it will take a long time for the hazardous material to clear the area, c) if buildings cannot be closed tightly or d) the hazardous material incident may increase in severity (such as an ongoing fire that might result in release of additional quantities of the hazardous material) . 14.10 Vulnerability and Risk Assessments As reviewed above in Sections 14.5 to 14.7, there are many fixed locations in Benton County with inventories of hazardous materials and a considerable volume of hazardous materials being transported to, from, within, or through Benton County. For both fixed and in transit hazardous materials, there are a wide variety of types and quantities of materials. Historically, the safety record for hazardous materials has been good, with relatively few, mostly minor HAZMAT incidents. Nevertheless, there is a potential for larger HAZMAT incidents in Benton County. A brief synopsis of the probable impacts of HAZMAT incidents on Benton County is given below in Table 14.13. Table 14.13 Probable Impacts of Hazmat Incidents on Benton County Inventory Probable Impacts Portion of Benton County affected Most hazmat incident impacts would be localized near source of spill, but major spills could have extensive evacuation zones and affect a significant portion of a community in Benton County Buildings Negligible impact, except for explosion incidents very near buildings Streets within Benton County Temporary street closures likely Roads to/from Benton County Temporary road closures likely Electric power Generally minor impacts, except for explosion incidents very near infrastructure Other Utilities Generally minor impacts, except for explosion incidents very near infrastructure or spills which release hazardous materials into rivers or reservoirs providing public water supply Casualties Potential for casualties (deaths and injuries), depending on location and identify of hazardous material(s) involved, time of day and effectiveness of evacuations 14.11 Summary and Mitigation Strategies 14.11.1 Planning and Response Hazardous materials vary dramatically in their degree of toxicity to humans. The impact of a hazardous material release incident on an affected community depends on several factors including: a) the toxicity of the hazardous material, b) the quantity of the hazardous material released, c) the dispersal characteristics of the hazardous material, d) the local conditions such as wind direction and topography, and e) the efficacy of response and recovery actions. Effective mitigation planning and effective emergency response planning can help reduce the number or frequency of hazardous materials incidents and also reduce the severity of incidents that do occur. In combination, these benefits can significantly reduce the negative impacts of hazardous materials incidents on affected communities. The general principles of mitigation planning, emergency response planning (and training) are well standardized and practiced by Benton County and the various communities in Benton County. 14-24 Perhaps the single most critical factor in enhancing both mitigation planning and emergency response planning is specific inventory awareness for major hazardous materials sites within each jurisdiction. Specific inventory awareness means detailed 14-25 knowledge of the types of hazardous materials, quantities of hazardous materials and locations of every location in a jurisdiction with significant quantities of hazardous materials. In this context, what constitutes a significant quantity varies depending on the toxicity of the material, the dispersal characteristics and the nature and population of nearby areas likely to be affected by hazardous materials incidents. The Office of State Fire Marshall?s Hazardous Substance Information System (HSIS) database contains a vast amount of information on the inventories of hazardous materials at fixed locations in Benton County. This detailed inventory information along with data hazardous materials being transported within or through Benton County, provides the basic data for specific inventory awareness. In combination, with the chemical data and emergency response information provided in the 2004 Emergency Response Guide and in other sources, these are the basic data necessary for effective planning and effective emergency response. The complexity and overload of information is compounded by numerous labeling, placarding, and classification systems for hazardous materials, with countless cross references to guide numbers, material safety reports and so on. Because of this vast amount of complex information, effective mitigation planning and emergency response planning must occur before an incident occurs, not after. During an incident, the most effective response is precluded and impossible to achieve if emergency personnel are thumbing through databases trying to figure out what hazardous materials are at a given location and what the appropriate response precautions and protocols are for the specific materials involved in a hazardous materials incident. Specific inventory awareness means that for every site with hazardous materials of sufficient toxicity, dispersal characteristics and quantities to pose a significant life safety risk to on-site employees and nearby residents must be identified in advance. Ideally, Benton County should have detailed specific inventory awareness of every significant fixed site in its jurisdiction. Similarly, each jurisdiction should have specific inventory awareness of the most toxic, most common, large volume shipments of hazardous materials within and through the jurisdiction. For each hazardous material deemed to pose a significant life safety threat, the necessary chemical data, response protocols, initial isolation distances, protection distances for small and large spills, and all other data necessary for safe and effective response should be compiled and readily available before incidents occur. 14.11.2 Mitigation Measures Specific inventory awareness is one cornerstone of reducing the potential for negative impacts from hazardous materials incidents by helping to optimize emergency planning and response planning. The other cornerstone is pro-active mitigation actions to reduce the number and severity of hazardous materials incidents. The most common mitigation measures for reducing the potential of damaging hazardous materials incidents are briefly summarized below. 14-26 14.11.2.1 Physical Safety Measures The tanks, other storage containers and transfer systems (valves, pipes etc.) for hazardous materials are frequently subject to damage in earthquakes, with a correspondingly high potential for accidental releases. Proper seismic design, bracing and anchoring of storage systems for hazardous materials can greatly reduce the potential of accidental releases during earthquakes. Bracing and anchoring measures for storage containers and transfer systems (e.g., piping) are often relatively inexpensive, with a large improvement in seismic performance. For small quantities of materials stored in bottles or jugs on shelving, bracing shelving and restraining containers so that they do not fall in earthquakes are particularly important. Over time, the storage containers and other material handling elements for hazardous materials may be changed many times. In some cases, later modifications may not be designed to the same seismic standards as the original installation or later modifications may compromise the seismic stability of the original installation. Therefore, periodic review and inspections of seismic design, bracing and anchoring are highly recommended for all hazardous material facilities. For facilities located in mapped flood plains or other areas subject to floodwaters there are two important physical safety measures. First, any containers subject to floating should be properly restrained. In many floods, improperly restrained tanks break free and float downstream, with high potential for negative impacts, including fires from tanks containing flammable materials as well as accidental releases of hazardous materials. Second, special precautions should be taken with water-reactive materials. Such materials should never be stored in low-elevation areas subject to flooding or in locations subject to water from storm water drainage or plumbing failures in a facility. 14.11.2.2 Standard Operating Procedures Standard operating procedures for storing, transporting, and handling hazardous materials should be strictly enforced at all facilities. Appropriate training for all staff, with review courses and appropriate protective gear are essential for safety. Rigorous inspection and enforcement of hazardous materials regulations (federal, state, and local) are an important part of the overall process of ensuring safety. 14.11.2.3 Mitigation and Emergency Response Planning Effective pre-event mitigation planning and emergency response planning can help reduce the severity of hazardous material incidents. From the mitigation planning perspective, specific inventory awareness of the types and quantities of hazardous materials present at each facility is particular important. Local fire departments and other responders should be thoroughly familiar with the specific inventory at each facility containing hazardous materials and with the appropriate response protocols for each hazardous material. First responders and emergency response teams must both have 14-27 the full range of protective gear and equipment necessary for their respective roles in responding to hazardous materials incidents. Emergency response planning should include thorough training in all aspects of hazardous materials response, including appropriate response protocols (procedures, protective gear and equipment). Frequent refresher training and frequent exercises (both tabletop and full field exercises) are essential for safe and effective emergency response. Training exercise should include both first responders and emergency response teams, to help ensure appropriate coordination of efforts during actual hazardous materials incidents. References 1. Handbook of Chemical Analysis Procedures, Federal Emergency Management Agency, U.S. Department of Transportation, and U.S. Environmental Protection Agency, U.S. Government Printing Office, 1988. 2. 2004 Emergency Response Guidebook (A Guidebook for First Responders During the Initial Phase of a Dangerous Goods/Hazardous Materials Incident), developed jointly by the U.S. Department of Transportation, Transport Canada, and the Secretariat of Transport and Communications of Mexico, 2004. 3. Hazardous Materials Emergency Response Teams Standard Operating Guidelines, May 7, 2001 Office of State Fire Marshal (Oregon). This series of about a dozen standard operating guidelines covers every main aspect of emergency response and recovery, including decisions to respond, levels of response, general response guidelines, mitigation methods, decontamination procedures, personal protective equipment, and others. 4. Hazardous Substance Information System (HSIS), Office of State Fire Marshall, Version 2.0P, August, 2004. Microsoft Access Database on CD-ROM. 5. Annual Report of Hazardous Materials Incidents in Oregon as Reported by Oregon Fire Service, Office of State Fire Marshal (Oregon), 2003 and earlier years. The table on the following page has HAZMAT mitigation action items from the master Action Items table in Chapter 14-28 This Page Left Blank Table 14.9 Hazmat Mitigation Action Items Mitigation Plan Goals Addressed Hazard Action Item Coordinating Organizations Timeline Life Safe Critical Facilities and Eme Services Protect Property Disas Resilient Econo P Education, Outr Partner Hazmat Incident Mitigation Action Items Short-Term #1 Ensure that first responders have readily available site-specific knowledge of hazardous chemical inventories in Benton County local fire and law enforcement agencies 1 year X X X Short-Term #2 Enhance emergency planning, emergency response training and equipment to address hazardous materials incidents. local fire and law enforcement agencies Ongoing X X X Long-Term #1 Modify existing codes to prohibit aggravating or creating a hazard in identified risk areas i.e. HAZMAT storage in a floodplain Community Development Departments 5 years X X X X Long-Term #2 Evaluate and assist with upgrade seismic bracing/anchoring for storage of large quantities of hazardous materials and for all Extremely Hazardous Material storage location Benton County Public Works (for county materials), city public works (for city materials), local industry, County Engineer, Benton County Emergency Management 10 years X X X X 14-29 This Page Left Blank 14-30 15.0 TERRORISM 15.1 Overview For mitigation planning, terrorism is broadly inclusive of a wide range of deliberate malevolent acts intended to damage building or infrastructure or to result in deaths and injuries. The possibility of international terrorist organizations targeting Benton County, is not zero, but is most likely small. However, Benton County is certainly subject to deliberate malevolent acts from many sources including vandals, mentally disturbed individuals, domestic terrorist groups (e.g., eco-terrorists), as well as by disgruntled residents, and past or present employees. The range of possible malevolent actions includes vandalism, arson, explosions and armed attacks, as well as use of chemical, biological, radiological or nuclear materials. Chemical attacks include deliberate release of on-site chemicals as well as deliberate dispersal of transported hazardous materials. Biological attacks include deliberate dispersal of biologically active materials (e.g., anthrax) capable of causing sickness or death. Radiological attacks include deliberate dispersal of radioactive materials, via dirty bombs (conventional explosives laced with radioactive materials) or other methods. Nuclear attacks include explosion of nuclear devices and the radioactive fallout from such explosions. The range of possible malevolent actions also includes cyber-terrorism, or deliberate disruption/damage of computer systems and data. Especially for utility systems, cyber- terrorism can also result in loss of service due to disruption/damage to automated SCADA (Supervisory Control and Data Acquisition) systems widely used by utilities. 15.2 Threat Spectrum For purposes of mitigation planning, we consider three sources of terrorist (malevolent) actions: outsiders, insiders, and hackers. In each case, we consider three levels of attack, with the levels reflecting the numbers of individuals involved, the level of technical knowledge or expertise, and the level of equipment or tools available. This threat spectrum is summarized below in Table 15.1. In Table 15.1, outsider means anyone who is not an employee of the facility under potential terrorist attack. Outsiders could be vandals, disturbed individuals, or members of domestic or international organized groups. For Benton County, the most likely terrorist or malevolent acts are minor vandalism or actions by disturbed individuals or employees. Deliberate terrorist actions are most likely from domestic groups, including eco-terrorists, and are less likely to be from international organizations. In Table 15.1, insider means anyone who is an employee of the target under potential attack. Acts of vandalism, theft and other relatively minor actions are common. Larger scale malevolent acts are less common but still occur with some frequency. Such acts 15-1 include larger scale damage, arson, explosives, and actions such as deliberate contamination of water supplies. In Table 15.1, computer hacker means individuals or groups using remote access to explore, vandalize, or destroy websites, computer databases and such. For utility systems, hackers can also impact SCADA systems and may affect system operations directly. Table 15.1 Threat Spectrum for Terrorist Actions Adversary Number of Adversaries Level of Knowledge Equipment Tools Weapons Objectives Outsider: high level 1 to small group Extensive knowledge of security systems, facilities and modes of attack hand tools, power tools, vehicles handguns or automatic weapons, incendiary devices, explosives, contaminants Extensive damage to critical facilities, widespread damage or casualties Outsider: medium level 1 to 3 Limited knowledge of security systems, facilities and modes of attack hand tools, power tools, vehicle handguns, incendiary devices, explosives, contaminants Damage or casualties Outsider: low level 1 or 2 Minimal knowledge of security systems, facilities and modes of attack hand tools None Vandalism, damage or casualties Insider: high level 1 Extensive knowledge of security systems, facilities, operations, policies and procedures On site tools, chemicals, equipment, vehicles handguns or automatic weapons, incendiary devices, explosives, contaminants Damage or casualties Insider: mediujm level 1 Moderate knowledge of security systems, facilities, operations, policies and procedures On site tools, chemicals, equipment, vehicles handguns, incendiary devices, explosives, contaminants Damage or casualties Insider: low level 1 Limited knowledge of security systems, facilities, operations, policies and procedures On site tools, chemicals, equipment, vehicles handgun or none Vandalism, damage or casualties Hacker: high level 1 to small group Full knowledge of IT intrastructure, security systems, SCADA systems Sophisticated hacker tools and methods N/A Destruction of data and systems, business operations Hacker: medium level 1 or 2 Moderate knowledge of IT intrastructure, security systems, SCADA systems Moderately sophisticated hacker tools and methods N/A Denial of servcie or disruption of some business services Hacker: low level 1 Limited knowledge of IT intrastructure, security systems, SCADA systems N/A N/A Minor cyber-vandalism to non-critical business areas The probable impacts of terrorist events on Benton County are summarized below in Table 15.2. For Benton County, the most likely terrorist (or other malevolent) events are small-scale events such as: 1) vandalism 2) minor damage by insiders (disgruntled employees) 15-2 3) minor damage by outsiders (extremist groups, mentally disturbed individuals), 4) computer hacking events, and 5) eco-terrorist actions. Larger scale events by domestic or international groups are possible, but appear relatively unlikely for Benton County, because there do not appear to be many targets of national significance in Benton County. However facilities of concern, based on the US Department of Justice methodology include the following: ? Good Samaritan Regional Medical Center ? Hewlett Packard ? OSU Sports Events ? Downtown Government Buildings (Benton County Courthouse, Law Enforcement Building, Commissioners, Corvallis Police). Table 15.2 Probable Impacts of Terrorist Incidents on Benton County Inventory Probable Impacts Portion of Benton County affected Localized impacts for minor incidents, large portions or the entire County for extremely unlikely major incidents Buildings Localized impacts to a single building or a few nearby buildings, except for extremely unlikely major incidents Streets within Benton County Some incidents may include temporary street closures Roads to/from Benton County Some incidents may include temporary road closures Electric power Some incidents may include temporary loss of electric power in localized parts of Benton County or for the entire County Other Utilities Some incidents may include temporary loss of utilities in localized parts of Benton County or for the entire County. Major damage to water or wastewater treatment plants could result in full or partial loss of service for extended time periods Casualties Small scale incidents may have no casualties or a small number of casualties. Possible, but unlikely, major events may result in significant casualties (deaths and injuries) 15.3 Mitigation Actions Evaluation of the threat of terrorist or other malevolent actions generally includes several steps: 1) determine critical facilities, 2) identify the specific adverse consequences to be avoided, 3) review the likelihood of malevolent actions, 4) evaluate existing countermeasures, and 5) implement a prioritized risk reduction plan. For Benton County, critical facilities include key elements of the water systems, electric power substations, facilities with large quantities of hazardous materials or any quantities of extremely hazardous materials (cf. Chapter 14) and important public or private 15-3 15-4 facilities such as OSU, schools, police and fire stations hospitals and major industrial sites. Potential targets for eco-terrorists include any major timber industry facilities. The most likely adverse consequences are vandalism and minor destructive actions by outsiders, insiders, or hackers. The evaluation of existing countermeasures should include: 1) physical security measures, such as fencing, locks and key control, structural integrity of critical assets, and detection capabilities such as intrusion detection systems, alarms, operational alarms for utility systems, and general security/access issues, 2) Cyber security measures, such as protection measures for business/operational computer systems and SCADA systems, including fire walls, access, security policies and protocols, including vendor access and system diagnostics, and 3) Security procedures and polices, such as personnel security, physical security, key and badge control, system control and operational data, chemical and other vendor deliveries, as well as security and emergency response training, exercises and drills. For Benton County vigilance and modest upgrades to existing physical security, cyber security, and security procedures and policies are probably all that are reasonably required. For the highest profile buildings or facilities, barriers to restrict vehicles reaching close proximity to the building or facility, to the extent practical, might also warrant consideration. Improving emergency response capabilities can also mitigate the potential impacts of terrorism or other malevolent deliberate actions in Benton County. Some types of actions, such as fires or explosions, are self-evident and emergency responders are well trained for dealing with such situations. Other types of actions such as release of radiological materials, bioterrorism, or contamination of water or food supplies may not be immediately recognized. For such types of actions, close cooperation with public health officials and awareness of the possibility of deliberate actions are important. Such situations also commonly require specialized expertise and equipment to detect and identify the radiological, biological or chemical materials used in an attack. Emergency response plans should be updated and expanded, as necessary, to cover such situations, including protocols for public notifications and information about appropriate public responses such as shelter in place or evacuation. The following table contains terrorism mitigation action items from the master Action Items table in Chapter 4. Table 15.3 Terrorism Mitigation Action Items Mitigation Plan Goals Addressed Hazard Action Item Coordinating Organizations Timeline Life Safe Critical Facilities and Emerg Protect Property Disaster Resilient Econo Public Education, Outr Partner Terrorism Mitigation Action Items Short-Term #1 Enhance emergency planning, emergency response training and equipment to address potential terrorism incidents. local fire and law enforcement agencies, facility managers Ongoing X X X X X Long-Term #1 Upgrade physical security detection and response capability for critical facilities, including water systems and for any high-profile facilities such as major timber industry facilities and sites with large quantities of hazardous materials facility managers 5 Years X X X X X 15-5 This Page Left Blank 15-6 tAPPENDIX A NATURAL HAZARDS RESOURCE DIRECTORY CONTENTS FLOOD RESOURCE DIRECTORY ...........................................................................5 County Resources..................................................................................................5 Watershed Councils .......................................................................................................................5 Willamette Riverkeepers ............................................................................................................5 Benton Soil and Water Conservation District.............................................................................5 Marys River Watershed Council ................................................................................................5 Luckiamute Watershed Council .................................................................................................5 MidCoast Watersheds Council...................................................................................................5 Long Tom Watershed Council ...................................................................................................5 Benton County Government...........................................................................................................6 Community Development...........................................................................................................6 Emergency Management/Emergency Management Council ....................................................6 OSU Extension ? Benton County...............................................................................................6 State Resources.....................................................................................................6 Oregon?s Wetlands Protection Program.........................................................................................6 Oregon Wetlands Joint Venture .....................................................................................................6 Oregon Department of Fish and Wildlife (ODFW)..........................................................................6 Oregon Division of State Lands (DSL) ...........................................................................................7 Oregon Water Resources Department (WRD)...............................................................................7 Federal Resources and Programs..........................................................................7 Federal Emergency Management Agency (FEMA) .......................................................................7 National Flood Insurance Program (NFIP).....................................................................................8 The Community Rating System (CRS)...........................................................................................8 The Floodplain Management Association ......................................................................................8 The Association of State Floodplain Managers..............................................................................8 Northwest Regional Floodplain Managers Association (NORFMA)...............................................8 FEMA?s List of Flood Related Websites.........................................................................................9 National Weather Service, Portland Bureau...................................................................................9 Office of Hydrology, National Weather Service..............................................................................9 Linn/Lincoln/Benton County Farm Services Agency, US Department of Agriculture.....................9 National Resources Conservation Service (NRCS), US Department of Agriculture......................9 United States Geological Survey (USGS)....................................................................................10 USGS Water Resources...............................................................................................................10 Bureau of Reclamation.................................................................................................................10 Army Corps of Engineers .............................................................................................................10 LANDSLIDE RESOURCE DIRECTORY .................................................................11 State Resources...................................................................................................11 Appendix A-1 Oregon State Building Codes Division .........................................................................................11 Oregon Department of Geology and Mineral Industries (DOGAMI) ............................................11 Oregon Department of Forestry (ODF) ........................................................................................11 Oregon Debris Flow Warning Page..............................................................................................12 Oregon Department of Transportation (ODOT)............................................................................12 Portland State University, Department of Geology ......................................................................13 Federal Resources and Programs ...............................................................................................13 Natural Resource Conservation Service (NRCS) ........................................................................13 US Geological Survey, National Landslide Information Center (NLIC)........................................13 Additional Resources............................................................................................14 2005 Oregon State Senate Bills 2,3,4,5.......................................................................................14 Oregon State Senate Bill 12.........................................................................................................14 Salem Landslide Ordinance .........................................................................................................14 Landslide Brochure.......................................................................................................................15 Nature of the Northwest................................................................................................................15 Publications ..........................................................................................................15 WILDFIRE RESOURCE DIRECTORY.....................................................................17 County Resources................................................................................................17 Adair Village Rural Fire District ....................................................................................................17 Alsea Rural Fire District................................................................................................................17 Blodgett-Summit Rural Fire District..............................................................................................17 Corvallis City Fire Department/Corvallis Rural Fire District..........................................................17 Monroe Rural Fire District.............................................................................................................17 Philomath Fire and Rescue..........................................................................................................17 Oregon Department of Forestry, Philomath Fire District..............................................................17 State Resources...................................................................................................18 Oregon Department of Forestry (ODF) ........................................................................................18 Office of the State Fire Marshal (OSFM)......................................................................................18 Federal Resources and Programs........................................................................18 Federal Wildland Fire Policy, Wildland/Urban Interface Protection..............................................18 National Fire Protection Association (NFPA) ...............................................................................19 National Interagency Fire Center (NIFC)......................................................................................19 United States Fire Administration (USFA) of the Federal Emergency Management Agency (FEMA) ......................................................................................................................................................19 Additional Resources............................................................................................19 FireFree Program to Promote Home Safety.................................................................................19 Firewise ? The National Wildland/Urban Interface Fire program .................................................20 Publications ..................................................................................................................................20 SEVERE WINTER STORM RESOURCES..............................................................22 Oregon Climate Service ...............................................................................................................22 National Oceanic and Atmospheric Administration (NOAA) ........................................................22 National Weather Service, Portland Bureau.................................................................................22 Appendix A-2 Additional Resources............................................................................................22 WINDSTORM RESOURCE DIRECTORY ...............................................................24 Oregon Climate Service ...............................................................................................................24 National Weather Service, Portland Bureau.................................................................................24 National Oceanic and Atmospheric Administration (NOAA) ........................................................24 Additional Resources............................................................................................24 EARTHQUAKE RESOURCE DIRECTORY.............................................................26 State Resources...................................................................................................26 Northwest GeoData Clearinghouse, Department of Geology ? Portland State University ..........26 Oregon Department of Geology and Mineral Industries (DOGAMI) ............................................26 Oregon Department of Consumer & Business Services-Building Codes Division.......................26 State Earthquake Legislation .......................................................................................................26 Senate Bill 13: Seismic Event Preparation ..............................................................................26 Senate Bill 14: Seismic Surveys For School Buildings............................................................27 Senate Bill 15: Seismic Surveys for Hospital Buildings ...........................................................27 US Geological Survey (USGS) ................................................................................................27 Building Seismic Safety Council (BSSC) .................................................................................28 Additional Resources............................................................................................28 Cascadia Region Earthquake Workgroup (CREW) .....................................................................28 Western States Seismic Policy Council Earthquake Program Information Center (WSSPC) .....28 Publications ..........................................................................................................29 VOLCANIC ERUPTION RESOURCE DIRECTORY................................................31 Federal Resources and Programs........................................................................31 Additional Resources............................................................................................31 Publications ..........................................................................................................31 Videotapes............................................................................................................32 Appendix A-3 This Page Left Blank Appendix A-4 Flood Resource Directory The following resource directory lists the resources and programs that can assist county communities and organizations. The resource directory will provide contact information for local, county, regional, state and federal programs that deal with natural hazards. County Resources Watershed Councils Willamette Riverkeepers Contact: Chair Address: 380 SE Spokane St., Suite 305, Portland. OR 97202 Phone: (503) 223-6418 Website: www.willamette-riverkeeper.org Email: info@willamette-riverkeeper.org Benton Soil and Water Conservation District Contact: Chair Address: 305 SW C Avenue, Suite 2, Corvallis, OR 97333 Phone: (541) 753-7208 Website: www.peak.org/~bentoncd Email: bentoncd@peak.org Marys River Watershed Council Contact: Coordinator Address: P.O. Box 1041, Corvallis OR 97339 Phone: (541) 758-7597 Website: www.marys-river-wc.peak.org Email: mrwc@peak.org Luckiamute Watershed Council Contact: Coordinator Address: Western Oregon University, Monmouth, Oregon 97361 Phone: (503) 838-8804 Website: www.wou.edu/las/natsci_math/geology/luckiamute Email: lwc@wou.edu MidCoast Watersheds Council Contact: Coordinator Address: 157 NW 15th St., Newport, OR 97365 Phone: (541) 265-9195 Website: www.midcoastwatershedcouncil.org Email: midcoast@newportnet.com Long Tom Watershed Council Contact: Coordinator Address: 751 South Danebo Ave., Eugene, OR. 97402 Phone: (541)683-6578 Website: www.longtom.org Email: Appendix A-5 Benton County Government Community Development Contact: Director Address: 360 SW Avery Avenue, Corvallis, OR 97333 Phone: (541) 766 - 6819 Website: www.co.benton.or.us/development Emergency Management/Emergency Management Council Contact: Manager Address: 180 NW 5th Street, Corvallis, OR 97330 Phone: (541) 766 - 6864 Website: www.co.benton.or.us/sheriff/ems OSU Extension ? Benton County Contact: Coordinator Address: Extension Service Administration, 101 Ballard Hall, Corvallis, OR 97331 Phone: (541)737-2713 Website: extension.oregonstate.edu/index.php Email: State Resources Oregon?s Wetlands Protection Program Oregon?s Wetlands Program was created in 1989 to integrate federal and state rules concerning wetlands protection with the Oregon Land Use Planning Program. The Wetlands Program has a mandate to work closely with local governments and the Division of State Lands (DSL) to improve land-use planning approaches to wetlands conservation. A Local Wetlands Inventory (LWI) is one component of that program. DSL also develops technical manuals, conducts wetlands workshops for planners, provides grant funds for wetlands planning, and works directly with local governments on wetlands planning tasks. Contact: Division of State Lands Website: http://statelands.dsl.state.or.us/ Oregon Wetlands Joint Venture The Oregon Wetlands Joint Venture is a coalition of private conservation, waterfowl, fisheries, and agriculture organizations working with government agencies to protect and restore important wetland habitats. Contact: Oregon Wetlands Joint Venture Website: http://wetlands.dfw.state.or.us/ Oregon Department of Fish and Wildlife (ODFW) ODFW?s mission is to protect and enhance Oregon?s fish and wildlife and their habitats for use and enjoyment by present and future generations. ODFW regulates stream activity and engages in stream enhancement activities. Contact: ODFW Address: 2501 SW First Avenue, PO Box 59, Portland, OR 97207 Phone: ( 503) 872-5268 Website: http://www.dfw.state.or.us/ Appendix A-6 Email: Odfw.Info@state.or.us Oregon Division of State Lands (DSL) DSL is a regulatory agency, responsible for administration of Oregon's Removal-Fill Law. This law is intended to protect, conserve, and make the best use of the state's water resources. It generally requires a permit from DSL to remove, fill, or alter more than 50 cubic yards of material within the bed or banks of waters of the state. Exceptions are in state scenic waterways and areas designated essential salmon habitat, where a permit is required for all in stream activity, regardless of size. DSL and the US Army Corps of Engineers may issue these permits jointly. Contact: Division of State Lands Address: 775 Summer Street NE, Suite 100, Salem, OR 97301-1279 Phone: (503) 378-3805 Fax: (503) 378-4844 Website: http://statelands.dsl.state.or.us/ Assistant Director: (503) 378-3805, ext. 279 Western Region Manager: (503) 378-3805, ext. 244 Oregon Water Resources Department (WRD) The WRD?s mission is to serve the public by practicing and promoting wise long-term water management. The WRD provides services through 19 watermaster offices throughout the state. In addition, five regional offices provide services based on geographic regions. The Department's main administration is performed from the central office in Salem. Contact: WRD Address: 158 12th ST. NE, Salem, OR 97301-4172 Phone: (503) 378-8455 Website: http://www.wrd.state.or.us/index.shtml http://www.co.washington.or.us/dptmts/wtr_mstr/wtr_mstr.htm Federal Resources and Programs Federal Emergency Management Agency (FEMA) FEMA provides maps of flood hazard areas, various publications related to flood mitigation, funding for flood mitigation projects, and technical assistance. FEMA also operates the National Flood Insurance Program. FEMA's mission is to reduce loss of life and property and protect the nation's critical infrastructure from all types of hazards through a comprehensive, risk-based, emergency management program of mitigation, preparedness, response and recovery. FEMA Region X serves the northwestern states of Alaska, Idaho, Oregon, and Washington. Contact: FEMA, Federal Regional Center, Region 10 Address: 228th St. SW, Bothell, WA 98021-9796 Phone: (425) 487-4678 Website: http://www.fema.gov To obtain FEMA publications: Phone: (800) 480-2520 To obtain FEMA maps: Contact: Map Service Center Address: P.O. Box 1038, Jessup, Maryland 20794-1038 Phone: (800) 358-9616 Fax: (800) 358-9620 Appendix A-7 National Flood Insurance Program (NFIP) Oregon has 256 flood-prone communities. Flood insurance is available to citizens in communities that adopt and implement NFIP building standards. The standards are applied to development that occurs within a delineated floodplain, a drainage hazard area, and properties within 250 feet of a floodplain boundary. These areas are depicted on federal Flood Insurance Rate Maps available through the county. Oregon?s Department of Land Conservation and Development is the state?s NFIP coordinating agency. Contact: National Flood Insurance Program Website: http://www.fema.gov/nfip/ The Community Rating System (CRS) The Community Rating System (CRS) recognizes community floodplain management efforts that go beyond the minimum requirements of the NFIP. Property owners within the county would receive reduced NFIP flood insurance premiums if the county implements floodplain management practices that qualify it for a CRS rating. Contact: National Flood Insurance Program Website: http://www.fema.gov/nfip/crs.htm The Floodplain Management Association The Floodplain Management website was established by the Floodplain Management Association (FMA) to serve the entire floodplain management community. It includes full- text articles, a calendar of upcoming events, a list of positions available, an index of publications available free or at nominal cost, a list of associations, a list of firms and consultants in floodplain management, an index of newsletters dealing with flood issues (with hypertext links if available), a section on the basics of floodplain management, a list of frequently asked questions (FAQs) about the Website, and a catalog of Web links. Contact: Floodplain Managers Association Website: http://www.floodplain.org Email: admin@floodplain.org The Association of State Floodplain Managers The Association of State Floodplain Managers is an organization of professionals involved in floodplain management, flood hazard mitigation, the National Flood Insurance Program, and flood preparedness, warning, and recovery. ASFPM fosters communication among those responsible for flood hazard activities, provides technical advice to governments and other entities about proposed actions or policies that will affect flood hazards, and encourages flood hazard research, education, and training. The ASFPM Web site includes information on how to become a member, the organization's constitution and bylaws, directories of officers and committees, a publications list, information on upcoming conferences, a history of the association, and other useful information and Internet links. Contact: The Association of State Floodplain Managers Address: 2809 Fish Hatchery Road, Madison, WI 53713 Phone: (608) 274-0123 Website: http://www.floods.org Northwest Regional Floodplain Managers Association (NORFMA) This site is a resource for floodplains, fisheries, and river engineering information for the Northwest. This site provides technical information, articles, and Internet links in the field of floodplain and fisheries management. Contact: Northwest Regional Floodplain Managers Association Website: http://www.norfma.org/ Appendix A-8 FEMA?s List of Flood Related Websites This site contains a long list of flood related Internet sites from ?American Heritage Rivers? to ?The Weather Channel,? and is a good starting point for flood information on the Internet. Contact: Federal Emergency Management Agency. Phone: (800) 480-2520 Website: http://www.fema.gov/nfip/related.htm National Weather Service, Portland Bureau The National Weather Service provides flood watches, warnings, and informational statements for rivers in Benton County. The NWS Portland office provides river level information online and by phone. Contact: National Weather Service, Portland Bureau Address: P.O. Box 2946, Portland, OR 97208-2946 Phone: (503) 261-9246 or (503) 261-9247 Fax: (503) 808-4875 Website: http://www.wrh.noaa.gov/Portland/public_hydro/ Office of Hydrology, National Weather Service The National Weather Service's Office of Hydrology (OH) and its Hydrological Information Center offer information on floods and other aquatic disasters. This site offers current and historical data including an archive of past flood summaries, information on current hydrologic conditions, water supply outlooks, an Automated Local Flood Warning Systems Handbook, Natural Disaster Survey Reports, and other scientific publications on hydrology and flooding. Contact: Office of Hydrology, National Weather Service Website: http://www.nws.noaa.gov/oh or http://www.nws.noaa.gov/oh/hic/ Linn/Lincoln/Benton County Farm Services Agency, US Department of Agriculture Stabilizing farm income, helping farmers conserve land and water resources, providing credit to new or disadvantaged farmers and ranchers, and helping farm operations recover from the effects of disaster are the missions of the U.S. Department of Agriculture's Farm Service Agency (FSA). Contact: County Executive Director Address: Phone: TBD Fax: Website: http://www.fsa.usda.gov/or/linncounty.hmtl National Resources Conservation Service (NRCS), US Department of Agriculture NRCS provides a suite of federal programs designed to assist state and local governments and landowners in mitigating the impacts of flood events. The Watershed Surveys and Planning Program and the Small Watershed Program provide technical and financial assistance to help participants solve natural resource and related economic problems on a watershed basis. The Wetlands Reserve Program and the Flood Risk Reduction Program provide financial incentives to landowners to put aside land that is either a wetland resource, or that experiences frequent flooding. The Emergency Watershed Protection Program (EWP) provides technical and financial assistance to clear debris from clogged waterways, restore vegetation, and stabilizing riverbanks. The measures taken under EWP must be environmentally and economically sound and generally benefit more that one property. Appendix A-9 Contact: Resource Conservationist Address: 256 Warner Milne Rd, Oregon City, Oregon 97045-4014 Phone: (503) 655-3144 Website: http://www.nrcs.usda.gov/ United States Geological Survey (USGS) The USGS website provides current stream flow conditions at USGS gauging stations in Oregon and throughout the Pacific Northwest. The Oregon USGS office is responsible for water-resources investigations for Oregon and part of southern Washington. Their office cooperates with more than 40 local, state, and federal agencies in Oregon. Cooperative activities include water-resources data collection and interpretive water-availability and water-quality studies. Contact: USGS Oregon District Office Address: 10615 S.E. Cherry Blossom Dr., Portland, OR 97216 Phone: (503) 251-3200 Fax: (503) 251-3470 Website: http://oregon.usgs.gov Email: info-or@usgs.gov USGS Water Resources This web page offers current US water news; extensive current (including real-time) and historical water data; numerous fact sheets and other publications; various technical resources; descriptions of ongoing water survey programs; local water information; and connections to other sources of water information. Contact: USGS Water Resources Phone: (503) 251-3200 Website: http://water.usgs.gov or http://water.usgs.gov/public/realtime.html Email: info-or@usgs.gov Bureau of Reclamation The mission of the Bureau of Reclamation is to manage, develop, and protect water and related resources in an environmentally and economically sound manner in the interest of the American public. Contact: Bureau of Reclamation, Pacific Northwest Region Address: 1150 N. Curtis Road, Boise, ID 83706 Phone: (208) 378-5012 Website: http://www.pn.usbr.gov/contact/index.shtml Army Corps of Engineers The Corps of Engineers administers a permit program to ensure that the nation?s waterways are used in the public interest. Any person, firm, or agency planning to work in waters of the United States must first obtain a permit from the Army Corps of Engineers. In Oregon, joint permits may be issued with the Division of State Lands. The Corps is responsible for the protection and development of the nation?s water resources, including navigation, flood control, energy production through hydropower management, water supply storage and recreation. Contact: US Army Corps of Engineers-Portland District, Floodplain Information Branch Address: P.O. Box 2946, Portland, OR 97208-2946 Phone: (503) 808-4874 Fax: (503) 808-4875 Website: http://www.nwp.usace.army.mil/ Appendix A-10 Landslide Resource Directory State Resources Oregon State Building Codes Division The Oregon Building Codes Division adopts statewide standards for building construction that are administered by state and local municipalities throughout Oregon. The One and Two-Family Dwelling Code and Structural Specialty Code contain provisions for lot grading and site preparation for the construction of building foundations. Both codes contain requirements for cut, fill, and sloping of the lot in relationship to the location of the foundation. There are also building setback requirements from the top and bottom of slopes. The codes specify foundation design requirements to accommodate the type of soils, the soil bearing pressure, and the compaction and lateral loads from soil and ground water on sloped lots. The building official has the authority to require a soils analysis for any project where it appears the site conditions do not meet the requirements of the code or special design considerations must be taken. ORS 455.447 and the Structural Code require a seismic site hazard report for projects that include essential facilities such as hospitals, fire and police stations, emergency response facilities, and special occupancy structures, such as large schools and prisons. Contact: Oregon State Building Codes Division Address: 1535 Edgewater St. NW, P.O. Box 14470, Salem, OR 97309 Phone: (503) 373-4133 Website: http:// www.cbs.state.or.us/external/bcd Oregon Department of Geology and Mineral Industries (DOGAMI) DOGAMI is an important agency for landslide mitigation activities in Oregon. Some key functions of DOGAMI are development of geologic data, and producing geologic hazard maps. The agency also provides technical resources for communities and provides data and geologic information to local, state, and federal natural resource agencies, industry, and private groups. Contact: DOGAMI Address: 800 NE Oregon Street, Suite 965, Portland, Oregon 97232 Phone: (503) 731-4100 Fax: (503) 731-4066 Website: http://sarvis.dogami.state.or.us Email: info@naturenw.org Oregon Department of Forestry (ODF) The mission of the Oregon Department of Forestry is to serve the people of Oregon through the protection, management, and promotion of a healthy forest environment, which will enhance Oregon's livability and economy for today and Appendix A-11 tomorrow. ODF regulates forest operations to reduce the risk of serious injury or death from rapidly moving landslides related to forest operations, and assists local governments in the siting review of permanent dwellings on and adjacent to forestlands in further review areas. As part of the requirements of Senate Bill 12, ODF is currently administering the deferral of certain forest operations on landslide-prone sites above homes and roads. The Department?s policy is that timber harvesting or road construction operations will be prohibited on land where landslides or debris flows pose a significant threat to human safety. Exceptions for salvage or other purposes are considered on an individual basis, but have been infrequent in keeping with the intent of preventing significant risks to human life.1 Oregon Debris Flow Warning Page The Oregon Debris Flow Warning page provides communities with up-to-date access to information regarding potential debris flows. The Debris Flow Warning system was initiated in 1997 and involves collaboration between ODF, DOGAMI, the Oregon Department of Transportation (ODOT), local law enforcement agencies, NOAA Weather Radio, and local media. The ODF is responsible for forecasting and measuring rainfall from storms that may trigger debris flows. Advisories and warnings are issued as appropriate. Information is broadcast over NOAA weather radio and provided to emergency services on the Law Enforcement Data System. DOGAMI provides additional information on debris flows to the media that convey the information to the public. ODOT also provides warnings to motorists during periods determined to be of highest risk for rapidly moving landslides along areas on state highways with a history of being most vulnerable. Information is available on the ODF website. Contact: ODF Address: 2600 State Street, Salem, OR, 97310 Phone: (503) 945-7200 Fax: (503) 945-7212 Website: http://www.odf.state.or.us/ Oregon Department of Transportation (ODOT) ODOT provides warnings to motorists during periods determined to be of highest risk of rapidly moving landslides along areas on state highways with a history of being most vulnerable to rapidly moving landslides. ODOT also monitors for landslide activity and responds to slide events on state highways. Contact: ODOT Transportation Building Address: 355 Capitol St. NE, Salem, OR 97310 Phone: (888) 275-6368 Website: http://www.odot.state.or.us Appendix A-12 Portland State University, Department of Geology Portland State University conducts research and prepares inventories and reports for communities throughout Oregon. Research and projects conducted through the Department of Geology at Portland State University include an inventory of landslides for the Portland metropolitan region after the 1996 and 1997 floods and a subsequent susceptibility report and planning document for Metro in Portland. Contact: Portland State University, Department of Geology Address: 17 Cramer Hall; 1721 SW Broadway, Box 751, Portland, OR 97207 Phone: (503) 725-3389 Website: http://www.geol.pdx.edu Federal Resources and Programs Federal Emergency Management Agency (FEMA), Landslide Fact Sheet FEMA?s website contains information on strategies to reduce risk and prevent loss from landslides and debris flows. Contact: Federal Regional Center, Region 10 Address: 130-228th St. SW, Bothell, WA 98021-9796 Phone: (425) 487-4678 Website: http://www.fema.gov/library/landslif.htm Natural Resource Conservation Service (NRCS) The NRCS produces soil surveys. These may be useful to local governments who are assessing areas with potential development limitations including steep slopes and soil types. They operate many programs dealing with the protection of natural resources. Contact: NRCS, Oregon Branch Address: 101 S.W. Main Street, Suite 1300, Portland, OR 97204 Phone: (503) 414-3200 Fax: (503) 414-3103 Website: http://www.or.nrcs.usda.gov US Geological Survey, National Landslide Information Center (NLIC) The NLIC website provides good information on the programs and resources regarding landslides. The page includes information on the National Landslide Hazards Program Information Center, a bibliography, publications, and current projects. USGS scientists are working to reduce long-term losses and casualties from landslide hazards through better understanding of the causes and mechanisms of ground failure both nationally and worldwide. Contact: National Landslide Information Center Phone: (800) 654-4966 Website: http://landslide.usgs.gov Appendix A-13 Additional Resources 2005 Oregon State Senate Bills 2,3,4,5 The 2005 Legislature passed Senate Bills 2, 3, 4, and 5 to initiate work towards seismic rehabilitation of vulnerable public schools and critical emergency response buildings. ? SB 2 ? appropriated funds to the Department of Geology and Mineral Industries to perform seismic needs assessments ? SB 3 ? Established a Seismic Rehabilitation Grant Committee to assess grant applications for rehabilitation projects of public buildings ? SB 4 and SB 5 ? Created Government Obligation Bonds to pay for SB 2 and SB 3. Oregon State Senate Bill 12 The 1997 Legislature passed Senate Bill 12 to address problems caused by landslides and debris flows. Provisions include: ? Allowing the Oregon State Forester to prevent timber harvest or road construction in or below areas identified by the Department of Forestry as ?high risk sites? and where homes or highways are in precarious locations; ? Allowing road officials to close roads that pose risk to human life because of landslides; ? Requiring State agencies to develop, and local officials to distribute, information about hazards of construction on sites that are vulnerable to landslides; ? Establishing a 10-member Task Force on Landslides and Public Safety to assess the problem and develop a solution. It includes legislators and representatives from state natural resource agencies, boards of commissions, local government, and the public; and ? Appointing the Department of Geology and Mineral Industries, with cooperation from local governments and the Department of Forestry, to identify and map rapidly moving landslides Senate Bill 12 defines a further review area as ?an area of land in which further site specific review should occur before land management or building activities begin.?1 Salem Landslide Ordinance The 1996 flood events contributed to two major landslide events, which forced the city into litigation. Through FEMA?s Hazard Mitigation Grant Program, the city of Salem, Marion County, and DOGAMI received $250,000 to map landslide areas and develop a landslide ordinance. The ordinance requires the preparation and approval of geological assessments before development occurs in areas identified with a moderate degree of hazard. Those areas then undergo a preliminary review of geologic conditions. The ordinance requires staff to determine if a geotechnical report requiring Appendix A-14 more information and detail than the geological assessment is necessary. This approach ensures adequate review of proposed development on private property where potentially greater risk requires more detailed information to fully identify and address the hazard. Additionally, prior to development, a declaratory statement indicating that the property is within an identified hazard area must be recorded on the property deed. Compliance with the ordinance is required as part of any land use permit and building permit for regulated activities within identified hazard areas.1 Landslide Brochure DOGAMI developed a landslide public outreach brochure in cooperation with several other state agencies. Forty thousand copies were printed in November 1997 and were distributed widely to building codes officials, county planners, local emergency managers, field offices of natural resource agencies, banks, real estate companies, insurance companies, and other outlets. The landslide brochure is available from DOGAMI, OEM, ODF, and the Department of Land Conservation and Development (DLCD).1 Contact: Department of Geology and Mineral Industries Address: 800 NE Oregon Street, Suite 965, Portland, Oregon 97232 Phone: (503) 731-4100 Fax: (503) 731-4066 Website: http://www.oregongeology.com Nature of the Northwest The Oregon Department of Geology and Mineral Industries and the USDA Forest Service jointly operate the Nature of the Northwest Information Center. The Center offers a selection of maps and publications from state, federal, and private agencies. Contact: The Nature of the Northwest Information Center Address: 800 NE Oregon Street #5, Portland, Oregon 97232 Phone: (503) 872- 2750 Fax: (503) 731-4066 Website: http://www.naturenw.org Email: Nature.of.Northwest@state.or.us Publications Olshansky, Robert B., Planning for Hillside Development (1996) American Planning Association. This document describes the history, purpose, and functions of hillside development and regulation and the role of planning, and provides excerpts from hillside plans, ordinances, and guidelines from communities throughout the US. Olshansky, Robert B. & Rogers, J. David, Unstable Ground: Landslide Policy in the United States (1987) Ecology Law Quarterly. This is about the history and policy of landslide mitigation in the US. Appendix A-15 Public Assistance Debris Management Guide (July 2000) Federal Emergency Management Agency. The Debris Management Guide was developed to assist local officials in planning, mobilizing, organizing, and controlling large-scale debris clearance, removal, and disposal operations. Debris management is generally associated with post-disaster recovery. While it should be compliant with local and county emergency operations plans, developing strategies to ensure strong debris management is a way to integrate debris management within mitigation activities. The Guide is available in hard copy or on the FEMA website. Contact: FEMA Distribution Center Address: 130 228th Street, SW, Bothell, WA 98021-9796 Phone: (800) 480-2520 Website: http://www.fema.gov/r-n-r/pa/dmgtoc.htm USGS Landslide Program Brochure. National Landslide Information Center (NLIC), United States Geologic Survey. The brochure provides good, general information in simple terminology on the importance of landslide studies and a list of databases, outreach, and exhibits maintained by the NLIC. The brochure also includes information on the types and causes of landslides, rock falls, and earth flows. Contact: USGS- MS 966, Box 25046 Address: Denver, Federal Center, Denver, CO 80225 Phone: (800) 654-4966 Web: http://geohazards.cr.usgs.gov/ Burns, Burns, James, and Hinchke. Landslides in Portland, Oregon Metropolitan Area (resulting from Storm of 1996: Inventory, Map Data, and Evaluation.) This paper provides an inventory of landslides resulting from the 1996 storm events. It is an excellent resource for determining the location and cause of many of the slides that occurred in this region. R. Jon Hofmeister. Slope Failures in Oregon. GIS Inventory for Three 1996/97 Storm Events. Oregon Department of Geologic and Mineral Industries. Special Paper 34. The objective of this project was to collect and consolidate data on Oregon landslides associated with severe storm events in February 1996, November 1996, and December 1996/January 1997. Appendix A-16 Wildfire Resource Directory County Resources Adair Village Rural Fire District Contact: Fire Chief Address: 6021 NE Marcus Harris Ave, Corvallis, OR 97330 Phone: (541) 745-5183 Fax: (541) Website: Alsea Rural Fire District Contact: Fire Chief Address: PO Box 81, Alsea, OR 97324 Phone: (541) 487-8701 Fax: (541) Website: Blodgett-Summit Rural Fire District Contact: Fire Chief Address: 36847 Happy Hollow Road Phone: (541) 456-4406 Fax: (541) 453-4406 Website: Corvallis City Fire Department/Corvallis Rural Fire District Contact: Fire Chief Address: 400 NW Harrison Blvd, Corvallis, OR 97330 Phone: (541) 766-6953 Fax: (541) Website: Monroe Rural Fire District Contact: Fire Chief Address: PO Box 411, Monroe OR 97456 Phone: (541) 847-5170 Fax: (541) Website: Philomath Fire and Rescue Contact: Fire Chief Address: P.O. Box 247, Philomath, OR 97370 Phone: (541) 929-3002 Fax: (541) Website: Oregon Department of Forestry, Philomath Fire District Contact: Fire Specialist Address: 24533 Alsea Highway, Philomath, OR 97370 Phone: (541) 758-8699 Fax: (541) Website: Appendix A-17 State Resources Oregon Department of Forestry (ODF) ODF?s Fire Prevention Unit is involved in interface wildfire mitigation and provides information about Oregon?s Wildfire Hazard Zones. The Protection From Fire section of the ODF website includes Oregon-specific fire protection resources. Wildfire condition reports can be accessed on the website as well. ODF?s Protection from Fire Program works to do the following: ? Clarify roles of ODF, landowners, and other agencies in relation to wildland fire protection in Oregon; ? Strengthen the role of forest landowners and the forest industry in the protection system; ? Understand and respond to needs for improving forest health conditions and the role/use of prescribed fire in relation to mixed ownerships, forest fuels and insects and disease; and ? Understand and respond to needs for improving the wildland/urban interface situation. Contact: Oregon Department of Forestry, Fire Prevention Unit Address: 2600 State Street, Salem, Oregon 97310 Phone: (503) 945-7440 Website: http://www.odf.state.or.us/fireprot.htm Office of the State Fire Marshal (OSFM) The Prevention Unit of Oregon?s Office of the State Fire Marshal contains 19 Deputy State Fire Marshals located in various regions. The responsibilities of these deputies include public education for local fire districts and inspection of businesses, public assemblies, schools, daycare centers, and adult foster homes. The State Fire Marshal?s Community Education Services unit works to keep Oregonians safe from fires and injury by providing them with the knowledge to protect themselves and their property. Contact: Oregon State Fire Marshal Address: 4760 Portland Road NE, Salem, Oregon 97305-1760 Phone: (503) 378-3473 Fax: (503) 373-1825 Website: http://159.121.82.250/ Oregon Laws on Fire Protection: http://159.121.82.250/SFM_Admin/firelaws.htm Email: oregon.sfm@state.or.us Federal Resources and Programs Federal Wildland Fire Policy, Wildland/Urban Interface Protection This is a report describing federal policy and interface fire. Areas of needed improvement are identified and addressed through recommended goals and actions. Website: http://www.fs.fed.us/land/wdfire7c.htm Appendix A-18 National Fire Protection Association (NFPA) This is the principal federal agency involved in the National Wildland/Urban Interface Fire Protection Initiative. NFPA has information on the Initiative?s programs and documents. Other members of the initiative include: the National Association of State Foresters, the US Department of Agriculture Forest Service, the US Department of the Interior, and the United States Fire Administration. Contact: Public Fire Protection Division Address: 1 Battery March Park, P.O. Box 9101, Quincy, MA 02269-9101 Phone: (617) 770-3000 National Interagency Fire Center (NIFC) The NIFC in Boise, Idaho is the nation?s support center for wildland firefighting. Seven federal agencies work together to coordinate and support wildland fire and disaster operations. These agencies include the Bureau of Indian Affairs, Bureau of Land Management, Forest Service, Fish and Wildlife Service, National Park Service, National Weather Service, and Office of Aircraft Services. Contact: National Interagency Fire Center Address: 3833 S. Development Avenue, Boise, ID 83705-5354 Phone: (208) 387-5512 Website: http://www.nifc.gov/ United States Fire Administration (USFA) of the Federal Emergency Management Agency (FEMA) As an entity of the Federal Emergency Management Agency, the mission of the USFA is to reduce life and economic losses due to fire and related emergencies through leadership, advocacy, coordination, and support. Contact: USFA, Planning Branch, Mitigation Directorate Address: 16825 S. Seton Ave., Emmitsburg, MD 21727 Phone: (301) 447-1000 Website: http://www.fema.gov/mit/wfmit.htm - Wildfire Mitigation Planning http://www.usfa.fema.gov/index.htm - USFA Homepage http://www.usfa.fema.gov/wildfire/- USFA Resources on Wildfire Additional Resources FireFree Program to Promote Home Safety In a pioneering effort to address wildfire danger in Bend, Oregon, four local agencies and a Fortune 500 corporation joined together to create "FireFree! Get In The Zone," a public education campaign designed to increase resident participation in wildfire safety and mitigate losses. Spearheaded by SAFECO Corporation, the partnership includes the Bend Fire Department, Deschutes County Rural Fire Protection District #2, Bend City Planning, and The Deschutes National Forest. The Oregon Department of Forestry and a number of local government agencies and businesses have joined the program. Contact: FireFree Address: 63377 Jamison St., Bend, OR 97701 Phone: (541) 318-0459 Appendix A-19 E-mail: dcrfpd2@dcrfpd2.com Website: http://www.firefree.org Firewise ? The National Wildland/Urban Interface Fire program Firewise maintains a Website designed for people who live in wildfire- prone areas, but it also can be of use to local planners and decision makers. The site offers online wildfire protection information and checklists, as well as listings of other publications, videos, and conferences. Contact: Firewise E-mail: firewise@firewise.org Website: http://www.firewise.org/ Publications National Fire Protection Association Standard 299: Protection of Life and Property from Wildfire. National Wildland/Urban Interface Fire Protection Program, (1991). National Fire Protection Association, Washington, D.C. This document, developed by the NFPA Forest and Rural Fire Protection Committee, provides criteria for fire agencies, land use planners, architects, developers, and local governments to use in the development of areas that may be threatened by wildfire. To obtain this resource: Contact: National Fire Protection Association Publications Phone: (800) 344-3555 Website: http://www.nfpa.org or http://www.firewise.org An International Collection of Wildland-Urban Interface Resource Materials (Information Report NOR-X-344). Hirsch, K., Pinedo, M., & Greenlee, J. (1996). Edmonton, Alberta: Canadian Forest Service. This is a comprehensive bibliography of interface wildfire materials. Over 2,000 resources are included, grouped under the categories of general and technical reports, newspaper articles, and public education materials. The citation format allows the reader to obtain most items through a library or directly from the publisher. The bibliography is available in hard copy or diskette at no cost. It is also available in downloadable PDF form. To obtain this resource: Contact: Canadian Forest Service, Northern Forestry Center, I-Zone Series Phone: (780) 435-7210 Website: http://www.prefire.ucfpl.ucop.edu/uwibib.htm Wildland/Urban Interface Fire Hazard Assessment Methodology. National Wildland/Urban Interface Fire Protection Program, (1998), NFPA, Washington, D.C. To obtain this resource: Contact: Firewise (NFPA Public Fire Protection Division) Phone: (617) 984-7486 Website: http://www.firewise.org Appendix A-20 Fire Protection in the Wildland/Urban Interface: Everyone?s Responsibility. National Wildland/Urban Interface Fire Protection Program. (1998). Washington, D.C.: Author. To obtain this resource: Contact: Firewise (NFPA Public Fire Protection Division) Phone: (617) 984-7486 Website: http://www.firewise.org Planning for Natural Hazards: The Oregon Technical Resource Guide, Department of Land Conservation and Development (July 2000). Produced by the Community Planning Workshop for the Department of Land Conservation and Development, this is a natural hazards planning and mitigation resource for Oregon cities and counties. It provides hazard-specific resources and plan evaluation tools. The document was written for local staffs and officials. The Technical Resource Guide includes a natural hazards comprehensive plan review, a hazard mitigation legal issues guide, and five hazard-specific technical resource guides, including: flooding, wildfires, landslides, coastal hazards, and earthquakes. This document is available online. You can also write, call, or fax to obtain this document: Contact: Natural Hazards Program Manager Address: 635 Capitol St. NE, Suite 200, Salem, OR 97301-2540 Phone: (503) 373-0050 Fax: (503) 378-6033 Website: http://www.lcd.state.or.us/hazards.html Appendix A-21 Severe Winter Storm Resources Oregon Climate Service The Oregon Climate Service (OCS) collects, manages, and maintains Oregon weather and climate data. OCS provides weather and climate information to those within and outside the state of Oregon and educates the citizens of Oregon on current and emerging climate issues. OCS also performs independent research related to weather and climate issues. Contact: Oregon Climate Service Address: Oregon Climate Service, Oregon State University Strand Ag Hall Room 316, Corvallis, OR 97331-2209 Phone: (541) 737-5705 Website: http://www.ocs.orst.edu Email: oregon@oce.orst.edu National Oceanic and Atmospheric Administration (NOAA) NOAA's historical role has been to predict environmental changes, protect life and property, provide decision makers with reliable scientific information, and foster global environmental stewardship. Contact: National Oceanic and Atmospheric Administration Address: 14th Street & Constitution Avenue, NW, Room 6013, Washington, DC 20230 Phone: (202) 482-6090 Fax: (202) 482-3154 Website: http://www.noaa.gov Email: answers@noaa.gov National Weather Service, Portland Bureau The National Weather Service (NWS) provides weather, hydrologic, and climate forecasts and warnings for the United States, its territories, adjacent waters and ocean areas, for the protection of life and property and the enhancement of the national economy. NWS data and products form a national information database and infrastructure, which can be used by other governmental agencies, the private sector, the public, and the global community. Contact: National Weather Service Address: 5241 NE 122nd Ave, Portland, Oregon 97230 Phone: (503) 326-2340 Website: http://nimbo.wrh.noaa.gov/Portland Email: clinton.rockey@noaa.gov Additional Resources Public Assistance Debris Management Guide, Federal Emergency Management Agency (July 2000). The Debris Management Guide was developed to assist local officials in planning, mobilizing, organizing, and controlling large-scale debris clearance, removal, and disposal operations. Debris management is generally associated with post-disaster recovery. While it should be compliant with local and county emergency operations plans, developing strategies to ensure strong debris management is a way to Appendix A-22 integrate debris management within mitigation activities. The Public Assistance Debris Management Guide is available in hard copy or on the FEMA website. Contact: FEMA Distribution Center Address: 130 228th Street, SW, Bothell, WA 98021-9796 Phone: (800) 480-2520 Fax: (425) 487-4622 Website: http://www.fema.gov/r-n-r/pa/dmgtoc.htm Appendix A-23 Windstorm Resource Directory Oregon Climate Service The Oregon Climate Service (OCS) collects, manages, and maintains Oregon weather and climate data. OCS provides weather and climate information to those within and outside the state of Oregon and educates the citizens of Oregon on current and emerging climate issues. OCS also performs independent research related to weather and climate issues. Contact: Oregon Climate Service Address: Oregon Climate Service, Oregon State University Strand Ag Hall Room 316, Corvallis, OR 97331-2209 Phone: (541) 737-5705 Website: http://www.ocs.orst.edu Email: oregon@oce.orst.edu National Weather Service, Portland Bureau The National Weather Service (NWS) provides weather, hydrologic, and climate forecasts and warnings for the United States, its territories, adjacent waters, and ocean areas for the protection of life and property and the enhancement of the national economy. NWS data and products form a national information database and infrastructure, which can be used by other governmental agencies, the private sector, the public, and the global community. Contact: National Weather Service Address: 5241 NE 122nd Ave, Portland, Oregon 97230 Phone: (503) 326-2340 Website: http://nimbo.wrh.noaa.gov/Portland Email: clinton.rockey@noaa.gov National Oceanic and Atmospheric Administration (NOAA) NOAA's historical role has been to predict environmental changes, protect life and property, provide decision makers with reliable scientific information, and foster global environmental stewardship. Contact: National Oceanic and Atmospheric Administration Address: 14th Street & Constitution Avenue, NW, Room 6013, Washington, DC 20230 Phone: (202) 482-6090 Fax: (202) 482-3154 Website: http://www.noaa.gov Email: answers@noaa.gov Additional Resources Public Assistance Debris Management Guide, Federal Emergency Management Agency (July 2000). The Debris Management Guide was developed to assist local officials in planning, mobilizing, organizing, and controlling large-scale debris clearance, removal, and disposal operations. Debris management is generally associated with post-disaster recovery. While it should be compliant with local and county emergency operations plans, developing strategies to ensure strong debris management is a way to Appendix A-24 integrate debris management within mitigation activities. The Public Assistance Debris Management Guide is available in hard copy or on the FEMA website. Contact: FEMA Distribution Center Address: 130 228th Street, SW, Bothell, WA 98021-9796 Phone: (800) 480-2520 Fax: (425) 487-4622 Website: http://www.fema.gov/r-n-r/pa/dmgtoc.htm Appendix A-25 Earthquake Resource Directory State Resources Northwest GeoData Clearinghouse, Department of Geology ? Portland State University Portland State University conducts geologic research and prepares inventories and reports for communities throughout Oregon. The GeoData Clearinghouse provides geologic information on earthquakes in the Northwest. It is especially useful for finding earthquake-related maps or links to geospatial mapping sites around the nation. Contact: Department of Geology Address: Portland State University P.O. Box 751, Portland OR 97207-0751 Phone: (503) 725-3022 Fax: (503) 725-3025 Website: http://www.metro.dst.or.us/metro/growth/gms.html Oregon Department of Geology and Mineral Industries (DOGAMI) The mission of the Department of Geology and Mineral Industries is to serve a broad public by providing a cost-effective source of geologic information for Oregonians and to use that information in partnership to reduce the future loss of life and property due to potentially devastating earthquakes, tsunamis, landslides, floods, and other geologic hazards. The Department has mapped earthquake hazards in most of western Oregon. Contacts: Deputy State Geologist, Seismic, Tsunami, and Coastal Hazards Team Leaders Address: 800 NE Oregon St., Suite 965, Portland, OR 97232 Phone: (503) 731-4100 Fax: (503) 731-4066 Website: http://sarvis.dogami.state.or.us/homepage Oregon Department of Consumer & Business Services-Building Codes Division The Building Codes Division (BCD) sets statewide standards for design, construction, and alteration of buildings that include resistance to seismic forces. BCD is active on several earthquake committees and funds construction related continuing education programs. BCD registers persons qualified to inspect buildings as safe or unsafe to occupy following an earthquake and works with OEM to assign inspection teams where they are needed. Contact: Building Codes Division Address: 1535 Edgewater St. NW, P.O. Box 14470, Salem, OR 97309 Phone: (503) 378-4133 Fax: (503) 378-2322 Website: http://www.cbs.state.or.us/external State Earthquake Legislation Senate Bill 13: Seismic Event Preparation Senate Bill 13, signed by the Governor on June 14, 2001, requires each state and local agency and persons employing 250 or more full-time employees to develop seismic preparation procedures and inform their employees about the Appendix A-26 procedures. Further, the bill requires agencies to conduct drills in accordance with Office of Emergency Management guidelines. These drills must include ?familiarization with routes and methods of exiting the building and methods of duck, cover and hold during an earthquake.? Each state and local agency and employer with 250 or more full-time employees shall maintain a file that documents the date the earthquake drill was conducted. Senate Bill 14: Seismic Surveys For School Buildings The Governor signed Senate Bill 14 on July 19, 2001. It requires the State Board of Higher Education to provide for seismic safety surveys of buildings that have a capacity of 250 or more persons and are routinely used for student activities by public institutions or departments under the control of the board. A seismic safety survey is not required for any building that has previously undergone a seismic safety survey or that has been constructed to the state building code standards in effect for the seismic zone classification. Subject to available funding, if a building is found to pose an undue risk to life and safety during a seismic event, a plan shall be developed for seismic rehabilitation or other seismic risk reducing activities. All seismic rehabilitation or other actions to reduce seismic risk must be completed before January 1, 2032, subject to available funding. Senate Bill 15: Seismic Surveys for Hospital Buildings The Governor signed Senate Bill 15 on July 19, 2001. It requires the Health Division to provide for seismic safety surveys of hospital buildings that contain an acute inpatient care facility. Seismic surveys shall also be conducted on fire stations, police stations, sheriffs? offices, and similar facilities subject to available funding. The surveys should be completed by January 1, 2007. A seismic survey is not required for any building that has undergone a survey or that has been constructed to the state building code standards in effect for the seismic zone classification at the site. Subject to available funding, if a building is evaluated and found to pose an undue risk to life and safety during a seismic event, the acute inpatient care facility, fire department, fire district or law enforcement agency using the building shall develop a plan for seismic rehabilitation of the building or for other actions to reduce the risk. All seismic rehabilitations or other actions to reduce the risk must be completed before January 1, 2022, subject to available funding. US Geological Survey (USGS) The USGS is an active seismic research organization that also provides funding for research. (For an example of such research, see Recommended Seismic Publications below). Contact: USGS, National Earthquake Information Center Address: Box 25046; DFC, MS 967; Denver, CO 80225 Phone: (303) 273-8500 Fax: (303) 273-8450 Website: http://neic.usgs.gov Appendix A-27 Building Seismic Safety Council (BSSC) The Building Seismic Safety Council (BSSC), established by the National Institute of Building Sciences (NIBS), deals with complex regulatory, technical, social, and economic issues and develops and promotes building earthquake risk mitigation regulatory provisions for the nation. Address: 1090 Vermont Avenue, NW, Suite 700, Washington, DC 20005 Phone: (202) 289-7800 Fax: (202) 289-109 Website: http://www.bssconline.org/ Additional Resources Cascadia Region Earthquake Workgroup (CREW) The Cascadia Region Earthquake Workgroup provides information on regional earthquake hazards, facts, and mitigation strategies for homes and businesses. CREW is a non-profit coalition of private and public representatives working together to improve the ability of Cascadia Region communities to reduce the effects of earthquake events. Members are from Oregon, Washington, California, and British Columbia. CREW?s goals are to: ? Promote efforts to reduce the loss of life and property; ? Conduct education efforts to motivate key decision makers to reduce risks associated with earthquakes; and ? Foster productive linkages between scientists, critical infrastructure providers, businesses, and governmental agencies in order to improve the viability of communities after an earthquake event. Contact: CREW, Executive Director Address: 1330A S. 2nd Street, #105; Mount Vernon, WA 98273 Phone: (360) 336-5494 Fax: (360) 336-2837 Website: http://www.crew.org Western States Seismic Policy Council Earthquake Program Information Center (WSSPC) WSSPC is a regional earthquake consortium funded mainly FEMA. Its website is a great earthquake resource, with information clearly categorized - from policy to engineering to education. Contact: Western States Seismic Policy Council Address: 125 California Avenue, Suite D201, #1, Palo Alto, CA 94306 Phone: (650) 330-1101 Fax: (650) 326-1769 E-mail: wsspc@wsspc.org Website: http://www.wsspc.org/home.html Appendix A-28 Publications Environmental, Groundwater and Engineering Geology: Applications for Oregon ? Earthquake Risks and Mitigation in Oregon, Yumei Wang, (1998) Oregon Department of Geology and Mineral Industries, Star Publishing. This paper deals with earthquake risks in Oregon, what is being done today, and what policies and programs are in action to help prevent loss and damage from seismic events. This article also gives a good list of organizations that are doing work in this field within the state. This article is somewhat technical but provides vital information to communities around the state. Contact: DOGAMI Address: 800 NE Oregon St., Suite 965, Portland, Oregon 97232 Phone: (503) 731-4100 Fax: (503) 731-4066 Website: http://sarvis.dogami.state.or.us/homepage Land Use Planning for Earthquake Hazard Mitigation: A Handbook for Planners, Wolfe, Myer R. et. al., (1986) University of Colorado, Institute of Behavioral Science, National Science Foundation. This handbook provides techniques that planners and others can utilize to help mitigate for seismic hazards. It provides information on the effects of earthquakes, sources on risk assessment, and effects of earthquakes on the built environment. The handbook also gives examples on application and implementation of planning techniques to be used by local communities. Contact: Natural Hazards Research and Applications Information Center Address: University of Colorado, 482 UCB, Boulder, CO 80309-0482 Phone: (303) 492-6818 Fax: (303) 492-2151 Website: http://www.colorado.edu/UCB/Research/IBS/hazards Using Earthquake Hazard Maps: A Guide for Local Governments in the Portland Metropolitan Region; Evaluation of Earthquake Hazard Maps for the Portland Metropolitan Region Spangle Associates, (1998/1999) Urban Planning and Research, Portola Valley, California. These two publications are useful for local governments concerned with land use in earthquake hazard areas. These publications do not explicitly address Benton County. However, these publications are written in clear and simplistic language and address issues such as how to apply earthquake hazard maps for land use decisions. Contact: DOGAMI Address: 800 NE Oregon St., Suite 965, Portland, Oregon 97232 Phone: (503) 731-4100 Fax: (503) 731-4066 Website: http://sarvis.dogami.state.or.us/homepage Public Assistance Debris Management Guide, Federal Emergency Management Agency (July 2000). Appendix A-29 The Debris Management Guide was developed to assist local officials in planning, mobilizing, organizing, and controlling large-scale debris clearance, removal, and disposal operations. Debris management is generally associated with post-disaster recovery. While it should be compliant with local and county emergency operations plans, developing strategies to ensure strong debris management is a way to integrate debris management within mitigation activities. The Public Assistance Debris Management Guide is available in hard copy or on the FEMA website. Contact: FEMA Distribution Center Address: 130 228th Street, SW, Bothell, WA 98021-9796 Phone: (800) 480-2520 Fax: (425) 487-4622 Website: http://www.fema.gov/r-n-r/pa/dmgtoc.htm Appendix A-30 Volcanic Eruption Resource Directory Federal Resources and Programs USGS-David A. Johnston Cascades Volcano Observatory (CVO) CVO provides accurate and timely information pertinent to assessment, warning, and mitigation of volcano hazards. It provides warnings during volcanic crises by monitoring volcanoes and interpreting results in the context of current hazard assessments. It also provides information for use in land-use management, emergency response plans, and public education. Contact: CVO Address: 1300 SE Cardinal Court, Vancouver, WA 98683 Phone: (360) 993-8900 Fax: (360) 993-8980 Website: http://vulcan.wr.usgs.gov/CVO_Info/framework.html or http://volcanoes.usgs.gov Additional Resources Institute of Geological & Nuclear Sciences Limited (GNS) GNS has an excellent website that describes volcanic hazards in New Zealand. It provides simple and informative descriptions of volcanic hazards that are useful for communities around the world. It discusses the types of volcanic hazards and emergency response and mitigation actions that could be implemented. Contact: Institute of Geological & Nuclear Sciences Address: 69 Gracefield Rd, PO Box 30-368, Lower Hutt, New Zealand Phone: (04) 570-1444 Volcano Specialists Contact: Wairakei Research Centre Address: State Highway 1 Private Bag 2000 Taupo New Zealand Phone: 64-7-374-8211 Fax: 64-7-374-8199 E-mail: info@ibhs.org Website: http://www.gns.cri.nz/earthact/volcanoes/hazards/index.htm Publications Volcanic-Hazard Zonation for Mount St. Helens, Washington Open-File Report 95-497 (1995) USGS-CVO Produced by the USGS-CVO in 1995, this report explains the various hazardous geologic processes of Mount St. Helens and the types of hazards and damages that have occurred at Mount St. Helens, and includes valuable references and suggested reading. Contact: USGS-CVO Address: 1300 SE Cardinal Court, Vancouver, WA 98683 Phone: (360) 993-8900 Fax: (360) 993-8980 Appendix A-31 Website: http://vulcan.wr.usgs.gov/Volcanoes/MSH/Hazards Volcano Hazards in the Mount Hood Region, Oregon Open-File Report 97-89 (1997) USGS-CVO Produced by the USGS-CVO in 1997, this report documents past hazardous events that have occurred at Mount Hood and includes several volcano hazard maps. It also discusses hazard forecasts and warnings as well as ways to protect oneself from volcano hazards. Contact: USGS-CVO Address: 1300 SE Cardinal Court, Vancouver, WA 98683 Phone: (360) 993-8900 Website: http://vulcan.wr.usgs.gov/Volcanoes/MSH/Hazards Volcano Hazards in the Three Sisters Region, Oregon Open-File Report 99-437 (1999) USGS-CVO Produced by the USGS-CVO in 1997, this report documents past hazardous events that have occurred at Mount Hood and includes several volcano hazard maps. It also discusses hazard forecasts and warnings as well as ways to protect oneself from volcano hazards. Contact: USGS-CVO Address: 1300 SE Cardinal Court, Vancouver, WA 98683 Phone: (360) 993-8900 Website: http://vulcan.wr.usgs.gov/Volcanoes/MSH/Hazards Videotapes ?Reducing Volcanic Risk,? USGS (24 minutes) This videotape showcases how people can lower their risk from volcanic activity. Three steps can prevent volcanic eruptions from becoming volcanic disasters: Identify Hazard Areas Monitor Volcanoes Develop Emergency Plan Video of volcanoes from around the world shows how these three steps saved lives when they were used. Reducing Volcanic Risk also describes the critical elements of emergency plans that made the difference between life and death for tens of thousands of people living in the shadows of active volcanoes. People must be informed of the hazards they face. Scientists and public officials must announce warnings clearly. And emergency plans must be tested and practiced ahead of time and used without hesitation when a volcano threatens to erupt. ?Understanding Volcanic Hazards,? USGS (24 minutes) This videotape features images of erupting volcanoes and graphically shows how volcanic activity can affect people, their property, and the land on which they live. Appendix A-32 The program focuses on seven types of volcanic hazards: ash falls, hot-ash flows (pyroclastic flows), lahars, landslides, tsunamis, lava flows, and volcanic gases. ?At Risk: Volcano Hazards from Mount Hood, Oregon,? USGS This video program describes and illustrates the types of volcano hazards posed by Mount Hood, Oregon, and shows areas near the volcano that could be affected by future activity. The video was produced to provide nearby residents, businesses, and public agencies basic information about future potential volcano hazards from the volcano. Located about 80 km east of Portland, Oregon, Mount Hood's recent activity has included debris avalanches (landslides), lahars, pyroclastic flows, and eruption of viscous lava. The video includes dramatic images of eruptions from volcanoes in the Caribbean, Japan, and Hawaii. Contact: Northwest Interpretive Association Address: 3029 Spirit Lake Highway, Castle Rock, WA 98611 Phone: (360) 274-2127 Fax: (360) 274-2101 Website: http://volcanoes.usgs.gov Public Assistance Debris Management Guide, Federal Emergency Management Agency (July 2000) Debris management is generally associated with post-disaster recovery. While debris-management should be compliant with local and county emergency operations plans, developing management strategies to ensure strong debris management during and after a natural hazard event is a way to integrate debris management with mitigation. The Public Assistance Debris Management Guide is available in hard copy or on the FEMA website. Contact: FEMA Distribution Center Address: 130 228th Street, SW, Bothell, WA 98021-9796 Phone: (800) 480-2520 Fax: (425) 487-4622 Website: http://www.fema.gov/r-n-r/pa/dmgtoc.htm Appendix A-33 This Page Left Blank Appendix A-34 APPENDIX B SPECIAL DISTRICTS/ MULTI-JURISDICTIONAL PLANS Overview There are several special districts/jurisdictions throughout Benton County. Some are county wide and administrative in nature, while others provide a day-to-day service to specific populations. The table summarizes the special districts/jurisdictions and the major and lesser hazards facing each special district, as described by the Hazard Specific chapters of the Benton County Multi-hazard Mitigation plan. Some hazards are generalized for all of Benton County (i.e. volcanic, earthquake), while others have a historical or a geographical specific impact for a district (i.e. wildfire or flooding). This comparison is to help special districts identify their specific mitigation priorities, as opposed to repeating the entire county list and losing visibility of the true risk facing their district. Special districts/jurisdictions have participated in the overall planning and plan development process. The districts/jurisdictions are encouraged to develop mitigation plans to address their specific major hazards facing the district and include their plan with the more general Countywide Multi-hazard Mitigation plan. As special district mitigation plans are created to address their localized hazard, they can be attached in this appendix so the overall county efforts and the district unique efforts are synchronized and supportive of each other. A format to help special districts capture their priorities is attached. By addressing the major or high priorities, districts can focus and begin mitigation efforts. To evolve the Benton County Pre-Disaster Mitigation Plan from a County Specific Plan to a Multi-Jurisdictional plan, a district/jurisdiction must: 1. Adopt the Benton County Plan 2. Augment the Benton County Plan with district/jurisdiction specific demographics and more detailed geographic information, if needed. 3. Augment the Benton County Plan by completing a district unique risk and threat assessment. 4. Identify district specific action items to reduce the risks facing their district. Appendix B-1 Appendix B-2 District Flood Winter Storm Land slide Wild Fire EQ Vol Dam Util/ TransHAZMATTerror City of Corvallis City of Monroe City of Philomath City of Adair Village North Albany Adair Rural Fire Protection District Alsea Rural Fire Protection District Blodgett Summit Rural Fire Protection District Corvallis Rural Fire Protection District Hoskins-Kings Valley Rural Fire Protection District Monroe Rural Fire Protection District North Albany Rural Fire Protection District Philomath Rural Fire Protection District Alsea Cemetery Maintenance District Summit Cemetery District Brownly Marshall Road District Chinook Drive Special Road District Country Estates Road District Hope Drive Road District Mary's River Estates Road District McDonald Forest Estates Special Road District North "F" Street Road District Oakwood Heights Road District Ridgewood Development Road District Rosewood Estates Road District Ryan Street Road District Skyline Terrace Road District Vineyard Mountain Road District Westwood Hills Road District Alpine County Service District Alsea County Service District Pioneer Village Service District Cascade View County Service District North Albany County Service District West Llewellyn Service District Junction City Water District Vineyard Mountain Parks and Recreation District Benton County School District 007J - Alsea Benton County School District 017J - Philomath Benton County School District 509J - Corvallis Benton County School District 25J - Monroe Benton County School District 8J - Albany = lesser impact = greater impact The following is an example of a special district and what their mitigation plan could be. Specific details would be required under the commentary, with more specific mitigation priorities to address each detail Special District: XYZ Fire Protection District Highest Impact Hazard Commentary Mitigation Priorities Wildland/Urban interface fires Identify specific high risk areas ? Implement fire safe practices ? Implement fuel load management ? Education of citizens in risk areas Earthquake Identify vulnerable stations and response resources ? Evaluate and retrofit vulnerable structures Hazmat Identify major sources of potential incidents ? Enhance response capability Appendix B-3 The Page Left Blank Appendix B-4