Design Report: Spring 2020Silverton Stormwater Improvements Gary Reyes • Gunter Roehrig • Jacob Ellston Eric Thomas • Abraham Salazar Civil & Environmental Engineering Capstone Spring 2020 Silverton Design Report: Stormwater Improvements Gary Reyes • Gunter Roehrig • Jacob Ellston Eric Thomas • Abraham Salazar Report Authors Evan Kristof Senior Instructor • Department of Civil and Environmental Engineering PORTLAND STATE UNIVERSITY Acknowledgments The Capstone team would like to acknowledge the following engineers for their mentorship and expertise. Shannon Williams, PE, Keller Associates Scott Nebeker, PE, Oregon David Seman, Former Engineer, KPFF Petra Schuetz, City of Silverton Public Works Director This report was prepared as part of a class project for the Civil and Environmental Engineering Project Management and Design course at Portland State University. Student authors developed the contents of this report; these contents do not necessarily reflect the views of Portland State University. The analyses, conclusions, and recommendations contained in the report should not be construed as an engineering report or used as a substitute for professional engineering services. Contents 4 About SCI 4 About SCYP 5 About Silverton, Oregon 6 Executive Summary 7 1.0 Project Understanding 9 2.0 Alternatives Analysis 15 3.0 Facility Design 18 4.0 Regulatory Compliance and Permitting 19 5.0 Conclusion 20 References 21 Appendices Spring 2020 Design Report: Stormwater Improvements About SCI The Sustainable Cities Institute (SCI) 2. Our Urbanism Next Center, which is an applied think tank focusing on focuses on how autonomous vehicles, sustainability and cities through applied e-commerce, and the sharing economy research, teaching, and community will impact the form and function of partnerships. We work across cities. disciplines that match the complexity of cities to address sustainability In all cases, we share our expertise challenges, from regional planning to and experiences with scholars, building design and from enhancing policymakers, community leaders, and engagement of diverse communities project partners. We further extend to understanding the impacts on our impact via an annual Expert-in- municipal budgets from disruptive Residence Program, SCI China visiting technologies and many issues in scholars program, study abroad course between. on redesigning cities for people on SCI focuses on sustainability-based bicycle, and through our co-leadership research and teaching opportunities of the Educational Partnerships for through two primary efforts: Innovation in Communities Network (EPIC-N), which is transferring SCYP 1. Our Sustainable City Year Program to universities and communities (SCYP), a massively scaled university- across the globe. Our work connects community partnership program that student passion, faculty experience, matches the resources of the University and community needs to produce with one Oregon community each innovative, tangible solutions for the year to help advance that community’s creation of a sustainable society. sustainability goals; and About SCYP The Sustainable City Year Program learning courses to provide students (SCYP) is a year-long partnership with real-world projects to investigate. between SCI and a partner in Oregon, Students bring energy, enthusiasm, in which students and faculty in courses and innovative approaches to difficult, from across the university collaborate persistent problems. SCYP’s primary with a public entity on sustainability value derives from collaborations and livability projects. SCYP faculty that result in on-the-ground impact and students work in collaboration with and expanded conversations for a staff from the partner agency through community ready to transition to a a variety of studio projects and service- more sustainable and livable future. 4 About Silverton, Oregon About Silverton, Oregon The first settlers came to the banks of Silver Creek, following timber and water power, in the 1800s. Silverton was incorporated in 1885. The young town was a trading and banking center of prominence and ranked among the most progressive towns of western Oregon. By 1921, Silverton industries were expansive wetlands area has benefited producing exports for other areas from the City’s excess reclaimed water and even some foreign countries. The since 2000, while the community Fischer Flour Mills on South Water benefits from trade the Garden draws Street was among the exporters. Power to the area. Silverton was recognized for the mill was obtained by damming for these reuse efforts as a “Community Silver Creek at a point near the present Water Champion” by the National Water pool, diverting water into a millrace that Reuse Association in 2018. ran along the creek to the mill and then Today, approximately 10,380 dumped back into the creek. residents call the city of Silverton The development and opening of the home. In addition to the Oregon Oregon Garden in the 1990s signify the Garden, the City features a historic success of a partnership between the downtown, hospital, community pool, Garden, a private enterprise attracting and access to nature activities including tourists to botanical displays, and the nearby Silver Falls State Park. city of Silverton. The Oregon Garden’s 5 Spring 2020 Design Report: Stormwater Improvements Executive Summary The City of Silverton is a small rural community in Marion County approximately 12 miles northeast of Salem. The City is named after Silver Creek, which runs through town and is the primary feature of the project site radiating from YMCA’s Silverton Community Swimming Pool. The City utilizes indigenous water supply to serve community needs, with two intakes in Abiqua Creek and as well as an intake at Silver Creek adjacent to the YMCA Pool. Downtime at this intake must be minimized so as to not compromise the City’s water supply if the other intake goes down or if it is needed to fill excess demand. Silver Creek is also critical habitat for steelhead, a native migratory fish, so water quality control must be addressed and National Marine Fisheries guidelines must be considered. The main purpose of intake improvement is to increase pipe capacity 150% from two cubic feet per second (cfs) to five cfs. As the initial leg of pipe from the intake goes under the YMCA Pool parking lot, the City is taking the opportunity to update the pool parking lot up to code for pool use. The scope of the 2020.SILV.01 team’s work includes the expansion of this parking lot. The city of Silverton requires low Students recommended that the impact design methods that are expanded area of the lot to the east economically feasible while mitigating be paved with permeable asphalt to surface runoff and limiting tree removal improve water filtration. The analysis as much as possible. To minimize costs question for this project was how to of the parking lot expansion, the new pave the extended portion of the lot. parking lot design retains the majority Non-permeable asphalt, permeable of existing asphalt. Working closely with pavers, and a no-build option were Keller Associates engineer Shannon also considered for the additional lot Williams, the 2020.SILV.01 capstone area. Weighing the accessibility, safety, team designed several iterations of the environmental, aesthetic, and economic parking lot to preserve as many trees in implications of using each material, the green area surrounding the existing including cost and maintenance, lot as possible while extending the lot students determined that permeable to the east and north. The final design asphalt would be the optimal material indicates two 12-inch diameter ash for the expansion. trees east of the existing lot would be To ensure adequate filtration of lot removed to make room for an additional overflow water, students designed twelve parking spaces, increasing two rain garden areas for the northern available parking 24% from 44 to 56. An side of current. The total area of the additional eight-inch pine tree would be proposed duel rain garden areas is 560 removed from the northwest corner of square feet, adequately filtering for the lot to install a rain garden. The rain the 14,000 square feet of impervious garden would filtrate water runoff from pavement at a design infiltration rate the lot, which would still primarily be of 2.5 inches per hour. Paired with the impervious asphalt. To further mitigate previous lot pavement, filtration for the environmental impact of the expansion expanded lot should be adequate to students recommended that the pine keep runoff from polluting Silver Creek. and ash trees be replaced with four saplings due to their advanced growth. 6 1.0 Project Understanding The city of Silverton, Oregon is updating its city parks and recreational facilities as part of their Parks and Recreation Master Plan. The Master Plan incorporates improvements to the YMCA Community Swimming Pool. The improvements include the expansion of the existing parking lot and onsite mitigation of stormwater runoff. The Portland State Capstone team, in collaboration with Keller Associates, developed a design to offer the most suitable solution possible for the city of Silverton and the community center. This report describes the existing conditions, project location, stakeholders, alternative analysis, and selection criteria, determining the best option for the City. 1.0 Project Understanding The purpose of the Silverton’s Parks and Recreation Master Plan is to add value to their greenspaces, parks, and recreational facilities. These resources are essential for maintaining a sense of community, health, and a state of well- being for Silverton’s residents. The City is looking to invest in the system includes a catch basin with swimming pool facility (which is under an oil filtration system that drains into contract with the YMCA), to enhance Silver Creek, located west of the YMCA community connectivity and services Pool. to its residents. The YMCA facility After assessing the current is a popular city attraction year- conditions, students pursued an option round. However, the facility sees its that will expand the parking lot to the peak capacities during the summer northeast of the lot (currently part of months. With the existing parking lot Old Mill Park). Additionally, a more configuration, the facility faces limited sustainable approach will govern the capacity to effectively manage all pool- proposed stormwater runoff mitigation, goers during the peak season. maintaining a low impact design The City is planning a project that characteristic. will include onsite stormwater runoff Completed work to date includes mitigation and the expansion of the existing condition assessment, low existing parking lot configuration at the impact design research, and minimal YMCA Pool. The existing parking lot CAD design work to delineate the consists of 44 standard parking stalls proposed expansion. The design will and three ADA accessible stalls. An follow City of Silverton codes and existing bike rack with a capacity for Design Standards, Americans with seven bikes is located southeast of the Disabilities Act (ADA), and Standard main entrance. The current stormwater Local Operating Procedures. 7 Spring 2020 Design Report: Stormwater Improvements 1.1 EXISTING SITE CONDITIONS The YMCA Pool is located southwest of city hall in the heart of downtown Silverton. The existing parking lot conditions consist of 44 standard parking stalls and three ADA-compliant stalls. The existing bike rack has a capacity for seven bikes. The parking lot is graded to drain towards the northwest corner of the lot where the stormwater infrastructure exists. The stormwater infrastructure consists of one catch basin and three manholes that house an oil filtration system, treating runoff before it drains into Silver Creek. FIG. 1 Aerial of site location and work area. 1.2 STAKEHOLDERS The project has several stakeholders with different levels of involvement as described below. • City of Silverton: The City will be funding and taking ownership of the project. Upon completion, the City will provide future maintenance and address questions from the public. • Keller Associates: Keller Associates is the main consulting firm for this project and will be the engineer of record. They will also oversee the project both during the design and construction phases. • Homeowners: During the construction phase, temporary parking lot closures may affect street parking in nearby areas. Furthermore, construction noise in the area may disturb nearby residents. • Local Businesses: During the construction phase, local businesses may experience disturbances due to material deliveries and heavy machinery used during the expansion of the parking lot. 8 2.0 Alternatives Analysis • Silverton Residents, Pool Users: The primary goal of the project is to expand the pool’s parking lot. During construction, the parking lot will close temporarily. However, the completion of the project will expand the parking lot’s capacity and in turn improve vehicle access to the pool.The primary project beneficiaries will be the residents of Silverton and YMCA pool users. The completion of the project will increase water resources for the City while also improving the YMCA facility. 2.0 Alternatives Analysis Students conducted an alternatives analysis to rate certain criteria for four alternative options concerning the pavement type proposed for the project. The alternatives included no build, non-permeable asphalt, permeable asphalt, and permeable parking stalls incorporated with permeable asphalt. The following sections define each alternative, review the selection criteria, and highlight the final decision. 2.1 CONSIDERED ALTERNATIVES The considered alternatives are described below. 2.1.1 Alternative 1: No Build be paved with permeable asphalt. The no build option maintains the Permeable asphalt allows runoff to existing parking lot configuration. be infiltrated directly through the The option mitigates the need for pavement and into the soil below, expansion or any additional stormwater treating water before it reaches the improvements. water table. Permeable surfaces minimize pooling that would otherwise 2.1.2 Alternative 2: Non-Permeable be generated by non-porous asphalt in Asphalt the lot. Alternative 2 paves an expanded lot with standard asphalt. Standard 2.1.4 Alternative 4: Permeable Paver pavement is considered a non- Stalls and Permeable Asphalt permeable surface, which increases the Alternative 4 is also an environmentally amount of uncaptured/untreated runoff. friendly option that allows the design In this option, runoff would be treated to be considered a LID. The design via the existing oil filtration system and includes two permeable material types: new rain gardens incorporated into the permeable asphalt and permeable parking lot expansion. pavers. As described in Alternative 3, permeable asphalt guides runoff into 2.1.3 Alternative 3: Permeable the soil below, allowing water treatment Asphalt for the Expanded Area before reaching the water table. In Alternative 3 utilizes an environmentally addition to the asphalt, each stall would friendly approach that implements incorporate permeable paving bricks Best Management Practices (BMPs), that also treat runoff while improving which would allow the design to be visual aesthetics. The pavers require considered a low impact design (LID). less maintenance than asphalt and can The expanded parking area would be easily repaired individually. 9 Spring 2020 Design Report: Stormwater Improvements 2.2 SELECTION CRITERIA This project maintains a variety of design options that will ideally meet Silverton’s expectations. Considerations include the parking lot expansion and the effects of increased stormwater runoff created by an increase in impermeable surface area. The team’s top priorities were to create an efficient parking design that will increase parking capacity without disrupting traffic flow and mitigate the increased stormwater runoff with sustainable infrastructure. Students developed a list of selection criteria to provide an understanding of how each design will meet the qualifications of these two priorities. The criteria are access, safety, environmental, aesthetics, maintenance, and cost. The following subsections will define each criterion and briefly explain how and why each design option received its score. Each section will receive a score from 1 to 5 and the description of said scores can be found in Table 2.1. 2.2.1 Access general spaces. However, the number Access considers several different of spaces fails to meet standards of aspects pertaining to the ability of the pool at maximum capacity. The traffic to move through the lot. The first possible pooling of water also affects consideration pertains to the ability accessibility. Therefore, Alternative 2 of personal vehicles to safely and was given a score of 3 indicated it is efficiently move through the parking lot. neutral for this category. Will these vehicles have ample parking • Alternatives 3 (Permeable Asphalt, to use during peak pool-going hours? Expanded Area) and 4 (Permeable The second consideration pertains Asphalt and Parking Stalls) alleviate to pedestrian and bicycle access. the pooling issues but having the Is the space safe for pedestrians same layout that does not satisfy and bicyclists? Do bicyclists have space requirements for pool easy access to bike parking? The capacity. Therefore, these options third consideration pertains to were given a score of 4, meeting ADA-compliant parking options to most criteria. accommodate those with disabilities. The final consideration pertains to how 2.2.2 Safety well the designs incorporate room for Safety relates to access but holds emergency access. Design access will distinct characteristics and was scored not vary from Alternatives 2 through 4 separately. Students considered the so it received a weight of 1. vehicle safety in each design including how effectively users can park and • Alternative 1 (No-Build ) received maneuver without interfering with the Lowest accessibility score. each other. Pedestrians and cyclists This option meets some of the must also be able to easily navigate accessibility criteria, however, ADA the design when entering and exiting requirements are not met because the pool facility. Finally, crime must there are not a sufficient number of be considered as parking lots can be ADA-compliant spaces. Therefore, magnets for a variety of crimes. Safety this option was given a score of 2. will be ranked according to the visibility • Alternative 2 (Non-Permeable throughout the parking lot and the Asphalt) increases the number of ADA amount of lighting incorporated in the compliant spaces and the number of design. Even though safety is important 10 2.0 Alternatives Analysis when considering the designs, it • Alternative 1 receives an received a weight of 1 because it does environmental score of 2, having not heavily affect the scope of the some environmental management project and the safety will not vary from features that could be better changes of paving material. managed. The new parking lot layout adds rain gardens to improve • Alternative 1 will add no additional stormwater management and lighting to deter criminal activity, planting strips to support wildlife. however the basic layout of the • Alternative 2 utilizes these features, current parking lot is such that however its non-permeable pavement drivers can maneuver within the lot is poorer environmentally relative reasonably safely. Alternative 2 adds to other alternatives. Therefore, this additional lighting to deter crime. option was determined to be neutral However, the possibility of ponding with a score of 3. due to differential settlements • Permeable pavement options have decreases safety. Alternatives 1 and 2 the lowest environmental impact, were given a score of 3. thus Alternatives 3 and 4 received a • Alternatives 3 and 4 reduce the score of 5. possibility of ponding and were given a safety score of 4, meeting 2.2.4 Aesthetics most requirements but not getting Students considered aesthetics when a score of 5 as 1-way lanes limit grading the designs. Since the site will maneuverability. be heavily used by the community, students sought an attractive design 2.2.3 Environmental that can be enjoyed by the users. This The environmental criterion examines grade was based purely on the visual how well the design’s ability to mitigate appeal of each design. Students gave stormwater runoff. The increase in this criterion a weight of 1 because it is the impermeable surface area poses not of major importance to the design a risk to overwhelm the current function. runoff management system. The design should consider green water • Alternative 1 scored the lowest infrastructure options that not only with a score of 2. The current site capture runoff but help infiltrate and is not visually appealing and when treat runoff. Ultimately this criterion was compared to the enhanced features based on how effectively the design of other options it is aesthetically captures and treats water to reduce its lacking. impact on Silver Creek. Environmental • Alternatives 2 and 3 both received aspects were a main focus when a score of 4. Both designs will look deciding between design options relatively the same as there is not a as students believe this parking lot large difference in looks between expansion is an opportunity to create porous and non-porous asphalt. better stormwater management. The • Alternative 4 scored the highest with environmental criterion received a a score of 5 as the addition of pavers weight of 2.5. enhances the visual appeal of a parking lot by incorporating designs similar to brick. 11 Spring 2020 Design Report: Stormwater Improvements 2.2.5 Maintenance 2.2.6 Cost Maintenance is a frequently overlooked Cost is an important factor when design aspect. Students envisioned considering designs as ambitious a design that requires very little designs often increase costs maintenance for both short- and considerably. To score Cost, students long-term scenarios. When deciding examined several factors, the first being on a score, students considered the cost of labor. Cost of labor includes the following categories. First, the the overall length of construction roadway surface should require very and amount of work required by the little cleaning and should not be contractor. Secondly, design feasibility subject to unconventional failures must be factored in as it must be leading to potholing. Next, the green deemed possible for a contractor infrastructure should be free of to efficiently complete the scope of maintenance outside of the normal work. Lastly, material cost needs to cleaning that is required. Lastly, be considered as increased design students considered the additional complexity can often increase overall maintenance that could be added from material costs. Therefore, the cost was the incorporation of new plants, trees, an overall driving factor in this project and landscaping. Maintenance received receiving a weight of 3. a weight of 1.5 as the variability of required upkeep changes immensely in • Alternative 1 received a score of 5 each design. as it would require no additional costs to leave the site as-is. For the • For Alternative 1 students scored remaining three alternatives students Maintenance as a 3. The current site only compared the difference in the is showing signs of deterioration, pavement as the overall layout would suggesting increases in required not be changed and would not affect maintenance are necessary to the cost between the three. maintain the integrity of the driving • Alternative 2 received a score of 4. surface. This option required basic asphalt • Alternative 2 scored the highest paving, which is the most cost- with a score of 4, as the non-porous effective of the three pavement pavement requires less cleaning options for both material and and the new pavement should have labor costs. The alternative is also increased integrity. considered feasible. • Alternative 3 received a score of 1, • Alternative 3 acquired the score as the porous pavement requires of 3 as both material and labor increased cleaning to maintain its costs would increase slightly while ability to infiltrate and treat runoff. It remaining feasible. is also subject to an increased failure • Alternative 4 received a score of 2. rate from moving vehicles. Both the material and labor costs will • Alternative 4 received a score of 2 rise significantly from the addition of as it still requires increased cleaning porous pavers. This alternative was frequency, but the incorporation of also considered slightly less feasible pavers increases the lifespan of the than other alternatives. stalls and if needed can be replaced individually instead of across whole sections. 12 2.0 Alternatives Analysis 2.2.7 Pugh Matrix criteria for each alternative. After the The following tables define the meaning criteria were scored, all of the scores of each score (1-5) and illustrate how were totaled. The highest scoring students’ overall design choice was alternative was Alternative 3, permeable derived. Students selected the design asphalt for the entire lot (Table 2.2). alternative with the highest tallied score Since Alternative 3 had the highest as the best fit design for the project. As rank, it was deemed to be the preferred described above, the team scored the alternative. 13 Spring 2020 Design Report: Stormwater Improvements TABLE 2.1 Score Description Description of Scoring 1 Does not meet the criteria description 2 Barely meets the criteria description 3 Neutral (meets some but not all) 4 Meets most of the criteria description 5 Meets the entire criteria description Criteria Weight Design Alternatives Alternative 1: Alternative 2: Alternative Alternative Preferred Alternative No-Build Non-Permeable 3: Permeable 4: Permeable Asphalt Asphalt for Paver Stalls Expanded Area and Permeable Asphalt Score Weighted Score Weighted Score Weighted Score Weighted Access 1 2 2 3 3 4 4 4 4 3 & 4 Safety 1 2 2 3 3 4 4 4 4 3 & 4 Environmental 2.5 2 5 3 7.5 5 12.5 5 12.5 3 &4 Aesthetics 1 2 2 4 4 4 4 5 5 4 Maintenance 1.5 3 4.5 3 4.5 1 1.5 2 3 1 & 2 Cost 3 5 15 4 12 3 9 2 6 1 Total 16 30.5 20 34 21 35 22 34.5 3 Final Rank 4 3 1 2 TABLE 2.2 Scores of each design alternatives 14 3.0 Facility Design 3.0 Facility Design The following section will discuss the final design proposal that will be submitted. It is organized into the following sections: overall design, mitigation of increased runoff, mitigation of current run, and additional issues that arose. 3.1 DESIGN CRITERIA To ensure the porous pavement The design criteria for the parking can manage the increased runoff, lot expansion considers the students used HydroCAD to produce implementation of BMPs, ADA, a runoff analysis. Students designed and city of Silverton requirements. the porous asphalt with no underdrain Incorporating innovative stormwater as the detailed geotechnical report management into the parking lot design provided by GeoEngineers found that requires using “best management soil on the site has an infiltration rate of practices” or LID. 0.5 inches per hour (in/hr). The storm was modeled as a 10yr Type IA 24-hr 3.2 EXPANSION OF PARKING LOT storm, which represents storms of low To address the lack of current parking intensity but long duration, a common spaces in the lot, students propose to occurrence in the Pacific Northwest. expand the current design to the east. Finally, students adjusted the time The proposed design includes a one frame to 30 hours to adhere to the lane route that will add an additional performance approach listed in the City 11 spaces to the parking lot while of Portland’s Stormwater Management maintaining the majority of the existing Manual. spaces (Appendix D, 6). Additionally, Overall, students concluded that the current travel directions will change the porous pavement could effectively from two-way to one-way with the manage the increased runoff based exception of the main entrance. Overall, on the analysis. By examining the the new design will be about 18,530 SF hydrograph, the peak runoff is 0.05 and will total of 56 parking spaces. CFS and the overall flow returns to zero within the 30-hour time frame, proving 3.3 MITIGATION OF INCREASED the design will handle the runoff RUNOFF (Appendix E, 13-18). As discussed in the prior section, the parking lot will have an increased area 3.4 MITIGATION OF CURRENT of about 4,530 square feet (SF). The RUNOFF increase leads to additional stormwater Two parking sections were designed runoff that needs to be managed in an for this project. One is the additional effective manner. Student alternatives parking area proposed that will use analysis considered several options porous asphalt on the east side of the including porous pavement, porous existing impervious asphalt. pavement with permeable pavers, For the impervious asphalt, there is and impermeable asphalt. Ultimately, approximately 14,000 SF calculated Alternative 3 was chosen, which for the analysis. To treat the runoff for included the incorporation of porous this section, students proposed two asphalt in the expanded section. planters to mitigate the water runoff. 15 Spring 2020 Design Report: Stormwater Improvements These planters would be located on the include passenger and emergency north side of the lot (Appendix D, 7). vehicles. These are the main two The Presumptive Approach Calculator types of vehicles that the parking lot (PAC) was used to estimate the size configuration needs to accommodate of the planter needed to mitigate the (Appendix D, 9-10). runoff. A geotechnical report from GeoEngineers specifically for this site 3.6 CONSTRUCTION COST showed that the soil has an infiltration The construction costs for the project rate of 0.5 in/hr. This value was used are relatively preliminary and will for calculations as well as the Open need further work as the project Pit Falling Head method with a 10-year develops. There are many different storm requirement. types of costs associated with the The final proposed size for the planter project, including labor, equipment, is 560 SF. This area was distributed in demolition, installation, materials, and two planter facilities. The resulting size temporary signage and barricades for the planter located on the NE corner among others. Labor costs include of the lot is about 7’ by 27’ and next to work done by all the contractors it, another planter with dimensions of throughout the construction of the 7’ by 53’ (Appendix D, 7). A hierarchy project. Equipment costs include category 3 and facility configuration C drilling vehicles for site investigation, were chosen for maximum efficiency. pavers for the asphalt, and compact The calculations performed suggested excavators for the removal of curb, a 543 SF planter. However, the actual earth, and light poles. Newly installed size of the two planters combined is items for the project include six new greater than the minimum required light poles, approximately 4,530 area by the PAC method, which makes SF of porous pavement, and a rain the design capable of infiltrating the garden for all runoff collected from estimated runoff (Appendix E, 2). the existing pavement. Material costs include asphalt, concrete, light 3.5 ADDITIONAL PROBLEMS THAT poles, subgrade, and PVC pipe. Other AROSE costs include temporary signage and Within the parking lot design process, barricades to help keep the public an additional complication arose safe distance. A detailed list showing that required the team to complete each item and its cost can be found in electronic turning templates to analyze Appendix A (1-3). the existing and proposed conditions of the parking lot configuration and traffic 3.7 CONSTRUCTION SCHEDULE flow. The electronic turning templates The construction schedule for the are CAD-based and illustrate or simulate YMCA Pool parking lot will occur in four vehicular paths that include starting, phases with a pre-construction phase turning, and ending maneuvers of a zero. vehicle. They are used to verify that access to and from the parking lot • Phase 0 includes pre-construction will not generate any complications. activities such as design, planning, Students generated electronic turning design approval, contract execution, diagrams for two types of vehicles and phase review. Phase 0 assumes (in accordance with AASHTO 2018 that a team working on this type of vehicle library dimensions) that 16 3.0 Facility Design design may take about 12 days to foundations is scheduled to be produce a design. completed in approximately six days. • Phase 1 is the period of construction. The details for these three items are The first task is equipment given in Appendix D. Additionally, mobilization followed by demolition ground preparation is scheduled in of the area where the new design this phase, where a geosynthetic will be implemented. Site grading layer will be placed above soil will provide the necessary slope for followed by coarse aggregate and water runoff to be captured by the lastly by porous asphalt. planter on the north side and by • In Phase 3, striping work begins. the porous asphalt in the new east Details are provided in Appendix D area. Piping will facilitate stormwater and will include all ADA stalls as well management following the details as van accessible stalls. Both new provided in Appendix D for the vegetated areas and new planters planter. In this phase, any utility such require landscaping. Details for the as gas or electric conduit must be planter layers are shown in Appendix securely moved if necessary. The D. Students suggest an additional east side of the parking lot has a bike rack be installed in the existing tree that must be removed for the area for bikes. Light installation expansion to take place. On the is scheduled for this phase. The north side, the vegetated area will foundation for the light poles is be reduced to about 8’ by 16’; design sufficient to sustain a maximum pole efforts were taken to conserve height of 30 feet. existing trees in this area. • In Phase 4, the project will be • In Phase 2, all concrete work for finalized. Cleaning and inspection are the curb, planter, and light pole included in the finalization process. 17 Spring 2020 Design Report: Stormwater Improvements 4.0 Regulatory Compliance and Permitting This section describes the regulatory agencies considered for the stormwater improvement project. 4.1 CITY OF SILVERTON (CITY re-striping of accessible parking spaces ENGINEERING DESIGN STANDARDS) must comply with state requirements. The City of Silverton has municipal Students reviewed and incorporated standards and requirements for these regulations, which included stripe construction and design. Design thickness, stripe locations, height for standards include parking layout, disabled stall signs, and signage types, disabled stalls, bike corrals, and the among others. required amount of parking spaces for a recreational building. 4.3 DEPARTMENT OF ENVIRONMENTAL QUALITY 4.2 OREGON TRANSPORTATION The Oregon Department of COMMISSION (STANDARDS FOR Environmental Quality (DEQ) is an ACCESSIBLE PARKING PLACES environmental regulatory agency. It AUGUST 2018) provides National Pollution Discharge The Oregon Transportation Commission Systems (NPDES) permits for Section (OTC), in accordance with the Oregon 401 Water Quality Certification for Post- Revised Statute (ORS) 447.233, adopted Construction Stormwater Management. standards for accessible parking spaces Any design proposed in this project will on January 22, 1992. ORS 447.223 create minimal runoff into Silver Creek, states that all new construction and in compliance with DEQ requirements. 18 Conclusion 5.0 Conclusion The proposed design focuses on expanding the existing YMCA pool parking lot while using the design as an opportunity to incorporate green infrastructure that mitigates and treats stormwater runoff. The expansion will increase the total avoided the removal of large trees and number of parking spaces from 44 to felt that protecting the current trees 56 while maintaining an efficient and outweighed additional parking spaces. safe layout for both passenger and As the city of Silverton and Keller emergency vehicles to navigate through Associates move forward on the the lot. The main benefit of this design project, students would like to highlight is the addition of green infrastructure. some next steps to complete the By removing the oil separator from the design. There are several important existing lot and incorporating infiltration factors that still need to be considered planters, runoff can be treated for and/or designed. First, the grading of any contaminants it is carrying. asphalt in the area highlighted on sheet Furthermore, the porous pavement 4 of the plan set needs to be measured. serves the same treatment purpose for Second, the routing of the planters’ runoff while removing any ponding that outflow pipes to the existing pipes of may occur from traditional pavement. the removed oil separator need to be The project’s major limitation was designed to account for stormwater not being able to incorporate more during large events. Lastly, the right-of- parking spaces due to the green space way boundaries are assumed and will surrounding the existing lot. Students need to be verified before construction. 19 Spring 2020 Design Report: Stormwater Improvements References References pertaining to project research Section 401 Water Quality Certification. used for the project report are listed below. (2018, March). Retrieved February 25, These references contain web links where 2020, from https://www.oregon.gov/deq/ the information can be retrieved and FilterDocs/401wqcertPostCon.pdf accessed for any further clarification. Slopes V Stormwater Requirements Leger, R. J. (2015, May 27). Slopes V Summary. (2017, February). Retrieved Innovative Ways to Show Storm Water February 2020, from http://trwc.org/ Quality Compliance. Retrieved February wp-content/uploads/2017/02/SLOPES-V- 25, 2020, from http://oregonewrg.org/ Stormwater-Requirements2.pdf wp-content/uploads/2015/05/SLOPES-V- Innovative-Ways-to-Show-Storm-Water- PRK-2.04-Replanting Requirements for Tree Quality-Compliance-FULL....pdf Removal on Private Property,City-Owned and Managed Sites and public rights-of- Oregon Transportation Commission Way. (2015, January). Retrieved May 2020, Standards for Accessible Parking Places from https://www.portlandoregon.gov/ August 2018. (2018, August). Retrieved citycode/article/526733 February 25, 2020, from https://www. oregon.gov/odot/Engineering/DOCS_ADA/ ADA_Standards-Accessible-Parking.pdf 20 Appendices Appendices The following appendices are attached. A. CONSTRUCTION COST ESTIMATE This section presents the list of materials and construction activities with estimated costs. B. CONSTRUCTION SCHEDULE This section presents a list of tasks, subtasks in a Gantt chart for the estimated time for preconstruction and construction. C. DEMOLITION PLAN This section provides details on the steps/precautions needed before construction begins. D. DRAWINGS Preliminary design sheets for proposed design. E. CALCULATIONS This section includes supporting calculations done for the light pole foundation bearing capacity, infiltration planter runoff capacity and planter bearing capacity of the walls and HydroCAD runoff analysis for the porous pavement. F. QC CHECKLIST This section presents a quality control checklist to ensure the rubric and group requirements are met. 21 Appendix A Construction Cost Estimate Cost Estimate Report Date: 05/31/2020 Stormwater Improvement Project Year 2020 Quarter 2 Unit Detail Report Prepared By: Melissa Boell Portland State University LineNumber Description Quantity Unit Total Incl. O&P Ext. Total Incl. O&P Division 01 General Requirements 015433200100 Rent excavator diesel hydraulic crawler mounted 1/2 CY capacity, Incl. 4.00 Day $702.11 $2,808.43 Hourly Oper. Cost. 015433200482 Rent backhoe-loader attachment, compactor, 20,000 lb., Incl. Hourly 3.00 Day $227.00 $680.99 Oper. Cost. 015433201910 Rent grader, self-propelled, 30,000 lb, Incl. Hourly Oper. Cost. 2.00 Day $1,745.79 $3,491.58 015433203000 Rent roller, vibratory, tandem, smooth drum, 20 H.P., Incl. Hourly Oper. 2.00 Day $420.46 $840.93 Cost. 015433204880 Rent loader, skid steer, wheeled, 10 CF, 30 HP, Incl. Hourly Oper. Cost. 2.00 Day $269.85 $539.70 015433401680 Rent barricade, portable with flasher 25 to 50 units, Incl. Hourly Oper. 3.00 Month $64.13 $192.39 Cost. 015433404020 Rent paver bituminous, rubber tires 8'wide 50 HP, diesel, Incl. Hourly 1.00 Day $907.98 $907.98 Oper. Cost. Division 01 General Requirements Subtotal $9,462.00 Division 02 Existing Conditions 022113090020 Topographical survey, conventional, minimum 2.00 Acre $660.75 $1,321.50 023213100020 Subsurface investigation, boring and exploratory drilling, initial field 1.00 Day $1,309.00 $1,309.00 stake out & determination of elevations, for borings 024113176000 Demolish, remove pavement & curb, remove concrete curbs, plain, 130.00 L.F. $5.22 $678.60 excludes hauling and disposal fees 024119250020 Selective demolition, saw cutting, each additional inch of depth over 3" 40.00 L.F. $1.37 $54.80 024210202500 Deconstruction of wood components, posts, up to 2 stories, excludes 40.00 L.F. $1.27 $50.80 handling, packaging or disposal costs Division 02 Existing Conditions Subtotal $3,414.70 1 LineNumber Description Quantity Unit Total Incl. O&P Ext. Total Incl. O&P Division 03 Concrete 033053401020 Structural concrete, in place, column (4000 psi), square, up to 2% 12.00 C.Y. $1,175.50 $14,106.00 reinforcing by area, 36" x 36", includes forms(4 uses), Grade 60 rebar, concrete (Portland cement Type I), placing and finishing Division 03 Concrete Subtotal $14,106.00 Division 07 Thermal and Moisture Protection 071713100100 Bentonite, rolls, with geotextile fabric both sides, 3/8" thick 4,530.00 S.F. $3.07 $13,907.10 Division 07 Thermal and Moisture Protection Subtotal $13,907.10 Division 10 Specialties 101453200100 Signs, stock, aluminum, reflectorized, high intensity, .080" aluminum, 3.00 Ea. $151.05 $453.15 24" x 24", excludes posts Division 10 Specialties Subtotal $453.15 Division 26 Electrical 260505100100 Conduit, rigid galvanized steel, 1/2" to 1" diameter, electrical demolition, 40.00 L.F. $3.02 $120.80 remove conduit to 10' high, including fittings & hangers 265613103000 Light poles, anchor base, aluminum, 20' high, excl concrete bases 6.00 Ea. $1,901.50 $11,409.00 Division 26 Electrical Subtotal $11,529.80 Division 31 Earthwork 311313203100 Selective clearing and grubbing, 8" to 12" diameter, remove selective 3.00 Ea. $420.00 $1,260.00 trees, on site using chain saws and chipper, excludes stumps Division 31 Earthwork Subtotal $1,260.00 Division 32 Exterior Improvements 321216140020 Asphaltic concrete paving, parking lots & driveways, 6" stone base, 2" 4,530.00 S.F. $2.78 $12,593.40 binder course, 1" topping, no asphalt hauling included 321613130300 Cast-in place concrete curbs & gutters, concrete, wood forms, straight, 560.00 L.F. $10.92 $6,115.20 6" x 18", excludes concrete 321723130500 Painted pavement markings, acrylic waterborne, white or yellow, 8" 400.00 L.F. $0.67 $268.00 wide, less than 3,000 LF 323333100012 Planters, precast concrete, sandblasted, 48" diameter, 24" high 5.00 Ea. $772.50 $3,862.50 329313100012 Ground cover, plants, pachysandra, excludes preparation of beds 5.00 C $200.00 $1,000.00 Division 32 Exterior Improvements Subtotal $23,839.10 Division 33 Utilities 2 LineNumber Description Quantity Unit Total Incl. O&P Ext. Total Incl. O&P 334211402040 Public storm utility drainage piping, corrugated metal pipe, galvanized 15.00 L.F. $19.51 $292.65 and bituminous coated with paved invert, 20' lengths, 16 ga., 8" diameter, excludes excavation and backfill Division 33 Utilities Subtotal $292.65 Subtotal $78,264.50 0.00% General Contractor's Markup on Subs $0.00 Subtotal $78,264.50 General Conditions 0.00% $0.00 Subtotal $78,264.50 General Contractor's Overhead and Profit 0.00% $0.00 Grand Total $78,264.50 3 Appendix B Construction Schedule Stormwater Improvements (2020.SILV.01) 2020 Design Report (Draft III) Appendix B Figure B.1 Construction Schedule. 1000 Phase 0 Preconstruction (c06/01/20 to 06/16/20, Duration 12 days) Task Title StartDate Finish Date Duration 1010 Design and planning 06/01/20 06/12/20 10 days 1020 Design approval 06/15/20 06/15/20 1 day 1030 Contract execution 06/16/20 06/16/20 1 day 1040 Phase exit review 2000 Construction (06/17/20 to 07/15/20, Duration 21 days) Task Phase 1 (8 days) StartDate Finish Date Time 2010 Equipment mobilization 06/17/20 06/17/20 1 day 2020 Erosion control 06/18/20 06/18/20 1 day 2030 Demolition & Removal 06/19/20 06/19/20 1 day 2040 Grading 06/22/20 06/23/20 2 days 2050 Underground piping (Stormwater) 06/24/20 06/24/20 1 day 2060 Utilities (light poles) 06/25/20 06/26/20 2 day 2070 Phase exit review Task Phase 2 (9 days) StartDate Finish Date Time 3010 Concrete work (Curbs) 06/29/20 06/30/20 2 days 3020 Concrete work (Planter walls) 07/01/20 07/02/20 2 days 3030 Concrete work (Light pole foundation) 07/03/20 07/06/20 2 days 3040 Ground preparation 07/07/20 07/07/20 1 day 3050 Geosynthetic mesh 07/08/20 07/08/20 1 day 3060 Asphalt installation 07/09/20 07/09/20 1 day 3070 Phase exit review Task Phase 3 (3 days) StartDate Finish Date Time 4010 Stripping work 07/10/20 07/10/20 1 day 4020 Landscape planter and green areas 07/13/20 07/13/20 1 day 4030 Bike rack installation 07/14/20 07/14/20 1 day 4040 Light installation 07/14/20 07/15/20 1 day 4050 Phase exit review Task Phase 4 (2 days) StartDate Finish Date Time 4040 Project clean up 07/15/20 07/15/20 1 day 4050 Project completion & inspection 07/26/20 07/16/20 1 day 4060 Phase exit review B.1 31 May 20 7 Jun 20 14 Jun 20 21 Jun 20 28 Jun 20 5 Jul 20 12 Jul 20 19 Jul 20 26 Jul 20 2 Aug 20 9 Aug 20 16 Aug 20 F S S M T W T F S S M T W T F S S M T W T F S S M T W T F S S M T W T F S S M T W T F S S M T W T F S S M T W T F S S M T W T F S S M T W T F S S M T W T F S S 6/16 6/26 7/9 7/15 7/17 (2020.SILV.01) Construction Schedule - page1 Appendix C Drawings Appendix D Calculations Stormwater Improvements (2020.SILV.01) 2020 Design Report (Draft III) Appendix D D. Calculation D.1 Light Pole Foundation Calculations D.2 Infiltration Planter Analysis D.3 Planter Wall Bearing Capacity Calculations. Stormwater Improvements (2020.SILV.01) 2020 Design Report (Draft III) Appendix D POLE FOUNDATION ANALYSIS For free-Top (unconstrained) Rigid Round Piers Using IBC Code Method Subjected to Vertical Load, Horizontal Load, and/or Moment. Table A1. IBC 2012 - Presumptive Load Bearing Values Vertical Foundation Class of Materials Pressure Lateral Bearing Pressure (below natural grade) (ksf) (ksf/ft.) 1. Crystalline bedrock 12.000 1.200 2. Sedimentary and foliated rock 4.000 0.400 3. Sandy gravel and/or gravel 3.000 0.200 4. Sand, silty sand, clayey sand, silty gravel and clayey gravel 2.000 0.150 5. Clay, sandy clay, silty clay, clayey silt, silt and sandy silt 1.500 0.100 Table A.2 PBOT Standard Street Light Pole Footing (Standard Drawing P-660) - Presumptive Values Description Value 1. Friction Angle f 26º 2. Effective Unit Weight 110 pcf D.1 Stormwater Improvements (2020.SILV.01) 2020 Design Report (Draft III) Appendix D Table A.3 (AASHTO 2001) Wind Pressure !" = 0.00256(1.3,!")#.$.% Description Fastest-mile wind speed Vfm 120mph Drag coefficient Cd 1 Coefficient for height above ground Ch 0.5 Design wind Pressure Pz or Ph 608 psf Input Data: Pier Data: Pier Foundation Diameter, D = 2.000 ft. Pier Height Above Soil, h1 = 2.000 ft. Soil Data: Unit Weight of Soil, g = 0.120 kcf Angle of Internal Friction, f = 26.00 deg. Depth to Resisting Surface, h2 = 0.000 ft. Allow. Vert. Bearing Pressure, Pa = 3.000 ksf Pier Loadings: Axial Load, Pv = 2.200 kips Horizontal Load, Ph = 0.610 kips Distance from Ph to Top/Pier, H = 10.000 ft. Externally Applied Moment, M = 0.000 ft-kips D.2 Stormwater Improvements (2020.SILV.01) 2020 Design Report (Draft III) Appendix D Results: Pier Embedment and Total Length: Pe = 0.610 kips Pe = Ph+(M/(H+h1+h2)) ("equivalent total" horizontal load) Pba = 0.200 ksf Pba = allowable lateral bearing pressure/ft. below grade (Table 1806.2) S1 = 0.392 ksf S1 = Pba*L/3 (allowable lateral soil pressure at 1/3 embedment depth) A = 1.822 A = 2.34*Pe/(S1*D) L = 5.88 ft. L = 0.5*A*(1+SQRT(1+(4.36*(H+h1+h2)/A))) (IBC 2012 Eqn. 18.1) Lt = 7.88 ft. Lt = h1+h2+L (total length) Pier End Bearing Pressure: Af = 3.14 ft.^2 Af = p*D^2/4 (pier base area) Wf = 3.71 kips Wf = (Af*Lt)*0.150 (pier weight) SPv = 5.91 kips SPv = Pv+Wf (total vertical load) P(bot) = 1.882 ksf P(bot) = SPv/Af Pa>=P(bot), O.K. Reference: 2012 International Building Code (IBC), Section 1807.3.2.1, pages 403-404 D.3 Stormwater Improvements (2020.SILV.01) 2020 Design Report (Draft III) Appendix D Infiltration Planter Analysis for size and infiltration capacity for a 2, 10- and 15-year storm event. Presumptive Approach Calculator (PAC) Data Sheets. Designer’s Statement The Silverton Stormwater improvement infiltration Planter Analysis was prepared by Abraham Salazar, meeting City of Silverton minimum Standards and normal Engineering standards. Project Name: 2020.SILV.01 Project Address: 421 S Water St Silverton, OR 97381 Designer: Abraham Salazar Last Modified: 5/20/20 1:27 PM Company: Portland State University Report Generated: 5/20/20 1:27 PM Catchment ID: Infiltration Planter PAC D.4 Stormwater Improvements (2020.SILV.01) 2020 Design Report (Draft III) Appendix D D.5 Stormwater Improvements (2020.SILV.01) 2020 Design Report (Draft III) Appendix D D.6 Stormwater Improvements (2020.SILV.01) 2020 Design Report (Draft III) Appendix D D.7 Stormwater Improvements (2020.SILV.01) 2020 Design Report (Draft III) Appendix D D.8 Stormwater Improvements (2020.SILV.01) 2020 Design Report (Draft III) Appendix D D.9 Stormwater Improvements (2020.SILV.01) 2020 Design Report (Draft III) Appendix D D.10 Stormwater Improvements (2020.SILV.01) 2020 Design Report (Draft III) Appendix D D.11 Stormwater Improvements (2020.SILV.01) 2020 Design Report (Draft III) Appendix D Analysis for Infiltration Planter Wall Design Minimum footing width (B) was found and checked to satisfy requirements for design using Rankine’s Theory for earth pressure coefficients. ` Figure D.1 Planter wall D.12 Stormwater Improvements (2020.SILV.01) 2020 Design Report (Draft III) Appendix D Trial 1 Trial 2 Trial 3 Assumed B (in) = 4 6 8 Assumed B (m) = 0.1016 0.1524 0.2032 L (in) = 0 1 2 L (m) = 0 0.0254 0.0508 Wall height, h (ft) = 3.5 3.5 3.5 Wall height, h (m) = 0.97 0.97 0.97 γf (kN/m3) = 20.0 20.0 20.0 ϕ'f (deg)= 36 36 36 γc (kN/m3) = 24 24 24 H (ft) = 4.5 4.5 4.5 H (m) = 1.37 1.37 1.37 Rankine active coefficient (Ka) = tan2(45-ϕ'/2) Ka = 0.26 0.26 0.26 Surcharge q (kPa) = 0 0 0 Pa1 (kN) =q*Ka*H = 0.0 0.0 0.0 Arm of Pa1 to Point A (m) = 0.0 0.0 0.0 Pa2 (kN) = (1/2)*Ka*γf*H^2 = 4.9 4.9 4.9 Arm of Pa2 to Point A (m) = 0.46 0.46 0.46 V1 (kN) = 0.0 0.5 1.0 Arm of V1 to Point A (m) = 2.5 2.5127 2.5254 V2 (kN) = 0.0 0.0 0.0 Arm of V2 to Point A (m) = 2.5 2.5127 2.5254 W1 (kN) = 11.6 11.6 11.6 Arm of W1 to Point A (m) = 2.25 2.25 2.25 W2 (kN) = 30.0 30.3 30.6 Arm of W2 to Point A (m) = 1.25 1.2627 1.2754 D.13 Stormwater Improvements (2020.SILV.01) 2020 Design Report (Draft III) Appendix D ΣFhoriz = 0 -> T = Pa1 + Pa2 T (kN) = 4.9 4.9 4.9 ΣFvert = 0 -> N = V1 + V2 + W1 + W2 N (kN) = 41.6 42.4 43.2 ΣMA = 0 -> x = (V1*arm + V2*arm + W1*arm + W2*arm - Pa1*arm - Pa2*arm)/N x (m) = 1.48 1.50 1.51 (a) Check overturning e (m) = B/2 - x -1.43 -1.42 -1.41 B/6 (m) = 0.02 0.03 0.03 e ≤ B/6 (Yes/No) Yes Yes Yes (b) Check sliding AASHTO Table 3.11.5.3-1 using mass concrete on coarse sand: δ (deg) = 30 30 30 Tult (kN) = N*tan(δ) = 24.0 24.5 25.0 FSsliding = (Tult)/(Pa1+Pa2) = 4.92 5.02 5.11 FSsliding ≥ 1.5 (Yes/No) Yes Yes Yes (c) Check bearing Known: qult (kPa) = 650 650 650 B' (m) = B - 2*e = 2.95 2.99 3.03 qavg (kPa) = N/B' = 14.1 14.2 14.3 FSbearing = qult/qavg = 46.08 45.81 45.54 FSbearing ≥ 3 (Yes/No) Yes Yes Yes Therefore, the planter walls will be ok with thickness of: 4”, 6” and 8”. If 6” thick is used, more concrete can be saved. D.14 Appendix E QC Checklist Stormwater Improvements (2020.SILV.01) 2020 Design Report (Draft III) Preparer Checker Checklist Item x x 3.0 Facility Design x x 3.1 Design Criteria x x 3.2 Mitigation of Increased Runoff x x 3.3 Mitigation of Current Runoff x x 3.4 Additional Problems that Arose x x 3.5 Construction Cost x x 3.6 Construction Schedule x x 4.0 Regulatory Compliance and Permitting x x 4.1 City of Silverton (City Design Standards) 4.2 Oregon Transportation Commission (Standards for Accessible Parking x x Places August 2018) x x 4.3 Department of Environmental Quality (DEQ) x x 5.0 Conclusion x x References x x APPENDICES x x A: Construction Cost Estimate x x B: Construction Schedule x x C: Drawings x x D: Calculations x x E: QC Check list Preparer Name: Abraham S Signature: ASR Date: 5/30/2020 Checker Name: Jacob E Signature: J E Date: 5/30/2020 E.2 Stormwater Improvements (2020.SILV.01) 2020 Design Report (Draft III) Group Capstone Team Project (2020.SILV.01) Preparer Checker Checklist Item x x GENERAL x x Grammar and Spelling x x Single, combined PDF x x Descriptive file name x x Consistent formatting x x Cover Page x x Project Title and ID x x Team # and Name x x Team Members and Names x x Client Name x x Relevant Figure and Description x x Table of Content x x All sections, subsections listed with page numbers x x Appendices listed with numbers x x Executive Summary x x 1.0 PROJECT UNDERSTANDING x x 1.1 Existing Site Conditions x x 1.2 Stake Holders x x 2.0 Alternative Analysis x x 2.1 Considered Alternatives x x 2.1.1 Alternative 1: No build x x 2.1.2 Alternative 2: Non-Permeable Asphalt 2.1.3 Alternative 3: Permeable Asphalt for the expanded x x Area 2.1.4 Alternative 4: Permeable Paver Stalls and Permeable x x Asphalt x x 2.2 Selection Criteria x x 2.2.1 Access x x 2.2.2 Safety x x 2.2.3 Environmental x x 2.2.4 Aesthetics x x 2.2.5 Maintenance x x 2.2.6 Cost E.1 SILV.01_RUNOFF_ANALYSIS_2.0 Type IA 24-hr 10 - Yr Rainfall=3.83" Prepared by HydroCAD SAMPLER 1-800-927-7246 www.hydrocad.net Printed 5/31/2020 HydroCAD® 10.10-3a Sampler s/n S24281 © 2020 HydroCAD Software Solutions LLC Page 7 This report was prepared with the free HydroCAD SAMPLER, which is licensed for evaluation and educational use ONLY. For actual design or modeling applications you MUST use a full version of HydroCAD which may be purchased at www.hydrocad.net. Full programs also include complete technical support,training materials, and additional features which are essential for actual design work. Time span=0.00-30.00 hrs, dt=0.01 hrs, 3001 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind method - Pond routing by Stor-Ind method Subcatchment 5S: PARKING LOT EAST Runoff Area=0.104 ac 100.00% Impervious Runoff Depth=3.60" Tc=100.0 min CN=98 Runoff=0.05 cfs 0.031 af Subcatchment 8S: Pre-Development Runoff Area=0.104 ac 0.00% Impervious Runoff Depth=1.34" Tc=5.0 min CN=72 Runoff=0.03 cfs 0.012 af Pond 4P: Pervious Pavement Peak Elev=-2.50' Storage=0.000 af Inflow=0.05 cfs 0.031 af Outflow=0.05 cfs 0.031 af Total Runoff Area = 0.208 ac Runoff Volume = 0.043 af Average Runoff Depth = 2.47" 50.00% Pervious = 0.104 ac 50.00% Impervious = 0.104 ac SILV.01_RUNOFF_ANALYSIS_2.0 Type IA 24-hr 10 - Yr Rainfall=3.83" Prepared by HydroCAD SAMPLER 1-800-927-7246 www.hydrocad.net Printed 5/31/2020 HydroCAD® 10.10-3a Sampler s/n S24281 © 2020 HydroCAD Software Solutions LLC Page 8 This report was prepared with the free HydroCAD SAMPLER, which is licensed for evaluation and educational use ONLY. For actual design or modeling applications you MUST use a full version of HydroCAD which may be purchased at www.hydrocad.net. Full programs also include complete technical support,training materials, and additional features which are essential for actual design work. Summary for Subcatchment 5S: PARKING LOT EAST Runoff = 0.05 cfs @ 9.11 hrs, Volume= 0.031 af, Depth= 3.60" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Type IA 24-hr 10 - Yr Rainfall=3.83" Area (ac) CN Description * 0.104 98 0.104 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 100.0 Direct Entry, Subcatchment 5S: PARKING LOT EAST Hydrograph Runoff 0.055 0.05 cfs Type IA 24-hr 0.05 10 - Yr Rainfall=3.83" 0.045 Runoff Area=0.104 ac 0.04 Runoff Volume=0.031 af 0.035 Runoff Depth=3.60" 0.03 0.025 Tc=100.0 min 0.02 CN=98 0.015 0.01 0.005 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Time (hours) Flow (cfs) SILV.01_RUNOFF_ANALYSIS_2.0 Type IA 24-hr 10 - Yr Rainfall=3.83" Prepared by HydroCAD SAMPLER 1-800-927-7246 www.hydrocad.net Printed 5/31/2020 HydroCAD® 10.10-3a Sampler s/n S24281 © 2020 HydroCAD Software Solutions LLC Page 9 This report was prepared with the free HydroCAD SAMPLER, which is licensed for evaluation and educational use ONLY. For actual design or modeling applications you MUST use a full version of HydroCAD which may be purchased at www.hydrocad.net. Full programs also include complete technical support,training materials, and additional features which are essential for actual design work. Summary for Subcatchment 8S: Pre-Development Runoff = 0.03 cfs @ 8.01 hrs, Volume= 0.012 af, Depth= 1.34" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Type IA 24-hr 10 - Yr Rainfall=3.83" Area (ac) CN Description * 0.104 72 Extg pervious, Pre-Lewis and Clark CN 0.104 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Subcatchment 8S: Pre-Development Hydrograph Runoff 0.03 0.03 cfs 0.028 Type IA 24-hr 0.026 10 - Yr Rainfall=3.83" 0.024 0.022 Runoff Area=0.104 ac 0.02 Runoff Volume=0.012 af 0.018 Runoff Depth=1.34" 0.016 0.014 Tc=5.0 min 0.012 CN=72 0.01 0.008 0.006 0.004 0.002 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Time (hours) Flow (cfs) SILV.01_RUNOFF_ANALYSIS_2.0 Type IA 24-hr 10 - Yr Rainfall=3.83" Prepared by HydroCAD SAMPLER 1-800-927-7246 www.hydrocad.net Printed 5/31/2020 HydroCAD® 10.10-3a Sampler s/n S24281 © 2020 HydroCAD Software Solutions LLC Page 10 This report was prepared with the free HydroCAD SAMPLER, which is licensed for evaluation and educational use ONLY. For actual design or modeling applications you MUST use a full version of HydroCAD which may be purchased at www.hydrocad.net. Full programs also include complete technical support,training materials, and additional features which are essential for actual design work. Summary for Pond 4P: Pervious Pavement Inflow Area = 0.104 ac,100.00% Impervious, Inflow Depth = 3.60" for 10 - Yr event Inflow = 0.05 cfs @ 9.11 hrs, Volume= 0.031 af Outflow = 0.05 cfs @ 9.13 hrs, Volume= 0.031 af, Atten= 0%, Lag= 1.0 min Discarded = 0.05 cfs @ 9.13 hrs, Volume= 0.031 af Routing by Stor-Ind method, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Peak Elev= -2.50' @ 9.13 hrs Surf.Area= 0.104 ac Storage= 0.000 af Plug-Flow detention time= 1.7 min calculated for 0.031 af (100% of inflow) Center-of-Mass det. time= 1.7 min ( 749.7 - 748.0 ) Volume Invert Avail.Storage Storage Description #1 -2.50' 0.062 af 30.20'W x 150.00'L x 1.50'H Gravel Storage 0.156 af Overall x 40.0% Voids Device Routing Invert Outlet Devices #1 Discarded -2.50' 2.500 in/hr Exfiltration over Horizontal area Discarded OutFlow Max=0.26 cfs @ 9.13 hrs HW=-2.50' (Free Discharge) 1=Exfiltration (Exfiltration Controls 0.26 cfs) SILV.01_RUNOFF_ANALYSIS_2.0 Type IA 24-hr 10 - Yr Rainfall=3.83" Prepared by HydroCAD SAMPLER 1-800-927-7246 www.hydrocad.net Printed 5/31/2020 HydroCAD® 10.10-3a Sampler s/n S24281 © 2020 HydroCAD Software Solutions LLC Page 11 This report was prepared with the free HydroCAD SAMPLER, which is licensed for evaluation and educational use ONLY. For actual design or modeling applications you MUST use a full version of HydroCAD which may be purchased at www.hydrocad.net. Full programs also include complete technical support,training materials, and additional features which are essential for actual design work. Pond 4P: Pervious Pavement Hydrograph Inflow 0.05 cfs Discarded 0.055 0.05 cfs Inflow Area=0.104 ac 0.05 Peak Elev=-2.50' 0.045 Storage=0.000 af 0.04 0.035 0.03 0.025 0.02 0.015 0.01 0.005 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Time (hours) Flow (cfs) SCI Directors and Staff Marc Schlossberg SCI Co-Director, and Professor of Planning, Public Policy, and Management, University of Oregon Nico Larco SCI Co-Director, and Professor of Architecture, University of Oregon Megan Banks SCYP Director, University of Oregon Sean Vermilya Report Coordinator Katie Fields SCYP Graduate Employee Danielle Lewis Graphic Designer