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Green Stormwater Infrastructure (GSI) is a complicated concept for the majority of the population due to complexities of the technologies and the dearth of research done on co-benefits offered by the multiple types of GSI. As GSI and its co-benefits are an interconnected complex system, it is important to create tools that can offer accurate information and predictions of the co-benefits. These tools also offer more chances to identify places for alternative funding for GSI beyond water related organizations. This study compares and evaluates the differences between three tools, the Green Values National Stormwater Management Calculator, the Environmental Protection Agency’s National Stormwater Calculator, and the Community-enabled Lifecycle Analysis of Stormwater Infrastructure Costs tool. Each tool offers a detailed analysis of different parts of the GSI selection, from life-cycle cost analysis to the variety of co-benefits offered to the level of performance of the BMP in stormwater management. This study is conducted by evaluating five representative rain gardens for the city of Philadelphia, and simulating their effects through each tool to examine data requirements and outputs. The results indicate functionality, ease of use, similarity and/or dissimilarity of the estimated hydrologic results, water quality, cost, and co-benefits of these tools. Co-benefit considerations may inform possibilities for leveraging funding from multiple utilities in a city. The Green Values Tool is the easiest to use, with the EPA Stormwater Calculator and the CLASIC Tool requiring more detailed inputs and handlings. The CLASIC Tool offers both the most detailed and highest number of co-benefits, the Green Values Tool offers some co-benefit analysis, and the EPA Stormwater Calculator did not cover co-benefits at all. All three tools contain a cost analysis function where the analysis for the CLASIC Tool and the Green Values Tool are similar, but the EPA Stormwater Calculator differs. The CLASIC Tool and the EPA Stormwater Calculator provide alike hydrologic budgets but the Green Values Tool estimates tends to vary. The CLASIC Tool is the only tool that provides water quality estimates. By analyzing and comparing the three tools, better choices can be made by governments and communities and offer more opportunities to look for alternative funding for GSI projects, all of which offer a healthier and greener future to the world.

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Nichols__Olivia.pptx (5443 kB)



Date Posted: 15 December 2022