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The Androscoggin Valley Soil and Water Conservation District (AVSWCD) expressed a need for the research and development of a semi-quantitative metric that can be used to determine priority stream barriers (eg. culverts; dams) to remove in Androscoggin and Sagadahoc Counties in Maine. In conjunction with a representative from the US Fish and Wildlife Service, Alex Abbott, the AVSWCD provided data about various stream sites within these two counties that had been recently surveyed. This included information about the aquatic ecological features of various stream habitats containing barriers and information about the physical characteristics of the barriers themselves.

Our proposed solution to this identified need was to develop a prioritized barrier removal list using a 0-1 passability index methodology. This methodology was chosen and developed to appeal to the needs of the AVSWCD in their efforts to enhance stream connectivity for aquatic wildlife in Androscoggin and Sagadahoc Counties in Maine. This method of valuation places a numeric weight on characteristics influencing a barrier’s likelihood of connecting multiple habitats, enhancing aquatic wildlife passage, and being considered feasible for removal. The 0-1 passabillity index utilized by Diebel et al. (2015) and Shaw et al. (2016) is a straightforward method for comparing barriers on a scale that considers multiple factors influencing how easily a barrier is passed. In addition to these methods, we consulted the NAACC Aquatic Connectivity Report (2016) in which Alex Abbott of US Fish and Wildlife provided scientific justifications for attributing certain values to characteristics present in our data.

After the application of weights to county data, it was discovered that Phippsburg, Woolwich, and Bowdoin were the three towns with the greatest number of high priority barriers in the first 100 barrier rankings. Each of these towns are located in Sagadahoc County, which is representative of the high presence of ecological value in these coastal habitats. Our recommendations for the district office are to group the prioritized first 100 barrier list by town, county, or another metric that would best appeal to grant funding opportunities. As listed in the appendix, our methodology includes opportunities for this project to be replicated in other counties across the state of Maine by substituting region-specific data into our index structure.