Innovations for LEAP GI: Green Infrastructure Analysis, Design, and Application in Detroit's Lower East Side

Abstract

This project combined social science knowledge of landscape cues to care and perceived safety with hydrologic modeling through GIS to design, site, and analyze the stormwater performance of green infrastructure best management practices (BMPs) for urban stormwater in Detroit. The main impetus behind this project is that Detroit suffers from frequent combined sewer overflow (CSO) events. It also has a high proportion of abandoned property and vacant land, where structures have been demolished, and there are many ongoing housing demolitions. Working closely with leaders of the Lower East Side Action Plan for Detroit, we designed novel BMPs to use the extensive vacant land as well as ongoing demolitions as part of green infrastructure. These BMPs also incorporated non-stormwater benefits; enhancing perceptions of personal safety and amenity landscape character in the most vacant neighborhoods of Detroit. We designed green infrastructure innovations to optimize “within block” infiltration, evapotranspiration, detention, and retention, anticipate transport of urban contaminants, minimize costs, and plan for long-term maintenance of the installations. We then conducted a spatial analysis to identify the location and capacity for runoff retention and CSO volume reduction for stormwater treatment of these BMPs throughout the city. The hydrologic model developed in this project analyzed the stormwater holding capacity of the BMPs by segmenting the study area into catchments, comparing the runoff for the catchments under multiple storm and surface imperviousness scenarios, and compared the original untreated runoff and final treated runoff volume estimates. Finally, we developed specific applications of these BMP’s for two actionable future redevelopment projects as proof-of-concept sites within the Lower Eastside of Detroit. The model demonstrated significant reductions in runoff for 2-year, 10-year, and 100-year storm events. However, BMPs were only sited in half of the catchments in the study area, resulting in both an unmet need for stormwater runoff reduction in some locations and excess runoff holding capacity in others. Therefore, the project provides an important stepping stone for future collaboration between LEAP and SNRE to consider the possibilities for improved networking and flow connections for stormwater within the district and the city.