Enabling Sustainable Irrigation: Determining the feasibility of landscape-based strategies

Abstract

Problem Fine soil particles (suspended sediment) in irrigation water can clog and damage irrigation equipment. Water-conserving and energy-saving strategies, like drip irrigation, low-flow sprinklers, and small-scale hydropower plants are particularly susceptible to damage, which hinders their broader adoption. The agricultural community is seeking a consistent, proactive sediment management strategy, at the district scale. Research My project develops and demonstrates a transferable method to determine whether landscape-based strategies might be feasible sediment filtration solutions for irrigation districts to field test. I conducted a review of journal articles, practitioner reports, and EPA best management practice recommendations to expand understanding of the problem. My synthesis of this literature review includes a typology of built forms that remove sediment from water; a typology of landscape-based strategies that employ those built forms; and strengths, weaknesses, opportunities, and threats (SWOT) analyses of three selected strategies: vegetated filters, compost filters, and constructed wetlands. Using my three selected landscape-based strategies as examples, I developed a framework for a fast, easy, step-by-step method that employs a landscape-scale analysis to select potential build sites, and a site-scale analysis to rule out landscape-based strategies that would not be feasible. Results I applied my method framework to the Farmers Irrigation District (FID) in Hood River, Oregon as a study site. I identified eight sources of sediment and nine potential build sites in the district, ruled out infeasible landscape-based strategies for each potential site, and found that implementation of the remaining potential strategies could be cost-effective. Finally, I created images of what the potentially feasible landscape-based strategies could look like in field testing.