Modeling low impact development in two Chicago communities

Abstract

Sustainable practices that will aid in reducing runoff volume and nutrient loading during storm events are needed in many urban areas. Continued assessment of the hydrologic impact of low impact development (LID) practices in urban communities is needed to support development and re-development of residential areas. An evaluation using the L-THIA LID model of two south-side Chicago communities with hypothetical implementation levels of LID features is presented in this study. The results revealed that incorporating LID practices such as porous pavement, and rain barrels, could have a noticeable impact on average annual runoff and the nonpoint source (NPS) pollutants carried in the runoff. Porous pavement on 50% of current parking lot space could result in an estimated 24% decrease in runoff volume. Additionally, the runoff reduction for all scenarios ranged from 2–24%. Hence, these results indicate that implementation of LID features in urban communities could provide substantial benefits.