GSI Impact Calculator

The Nature Conservancy in Pennsylvania and Delaware wanted to make economic analysis of green stormwater infrastructure more accessible to practitioners and community partners. Radbridge developed the GSI Impact Calculator, a web application based on the economic methods and spreadsheet created by One Water Econ. Users enter project details, adjust local assumptions, and compare expected benefits with installation and maintenance costs.

Interactive charts and downloadable summaries help users assess benefits related to flooding, water quality, heat, and other community conditions. They can use the results in early project planning, funding discussions, and public meetings. We also developed the GSI Impact Hub website to provide guidance and resources. Our ongoing role includes operating the application, providing technical support, and implementing updates with the project partners.