Impacts of Rainfall Distributions and Land Cover on the Effectiveness of Stormwater Best Management Practices

As urbanization continues and the effects of climate change intensify, optimizing the effectiveness of stormwater best management practices (BMPs) will be of utmost importance. Previous studies in the Clarksburg, Maryland area have focused on the impacts of different types of BMP infrastructure on stream health, finding conflicting results from sites with similar BMP implementation. The goal of this study was to determine what is causing different benthic outcomes by examining BMP storage capacity and how BMPs respond to varying rainfall events. The results showed that many BMPs are either under or overutilized during both extreme and typical rainfall events, indicating they are not large enough or not placed in a way to maximize their effectiveness. Given this and the lack of strong relationships between land cover types draining into BMPs and benthic outcomes, land cover composition of BMP drainage areas is likely not a great predictor of benthic outcomes by itself, as it fails to account for untreated flow due to limits in capacity.