This team met with Great Lakes cities representatives to prepare for the creation of an operational Great Lakes Cities Permeability Index (GLCPI), an assessment tool aimed at measuring and advancing the use of green infrastructure and its impacts on improving the water quality of the Great Lakes. Team members and partner cities (Chicago, IL; Evanston, IL; Ft. Wayne, IN; Milwaukee, WI) reviewed each city’s GIS capacity, Green Infrastructure programs, existing monitoring efforts, and potential BMP performance modeling tools. They identified research topics, made site visits, compared available data and identified potential conflicting elements between cities’ efforts. This research will lead to a larger project plan related to the GLCPI system components.