Daniels, Benjamin J.Yeakley, J. Alan2024-05-062024-05-062024-05-03Daniels, Benjamin J., and Jon Alan Yeakley. “Catchment-Scale Hydrologic Effectiveness of Residential Rain Gardens: A Case Study in Columbia, Maryland, USA.” Water 16, no. 9 (January 2024): 1304. https://doi.org/10.3390/w16091304.https://doi.org/10.3390/w16091304http://hdl.handle.net/11603/33589To mitigate the adverse impacts of urban stormwater on streams, watershed managers are increasingly using low-impact development and green infrastructure (LID-GI) stormwater control measures, such as rain gardens—vegetated depressional areas that collect and infiltrate runoff from rooftops and driveways. Their catchment-scale performance, however, can vary widely, and few studies have investigated the cumulative performance of residential rain gardens for event runoff control in intermediate-sized (i.e., 1–10 km²) suburban catchments. We modeled three years of continuous rainfall-runoff from a 3.1 km² catchment in Columbia, MD, USA, using the Storm Water Management Model (SWMM). Various extents of rain garden implementation at residential houses were simulated (i.e., 25%, 50%, 75%, and 100% coverage) to determine the effects on peak flow, runoff volume, and lag time. On average, treating 100% of residential rooftops in the catchment reduced peak flows by 14.3%, reduced runoff volumes by 11.4%, and increased lag times by 3.2% for the 223 rainfall events during the simulation period. Peak flow reductions were greater for smaller storm events (p < 0.01). Our results show that residential rain gardens can significantly improve the runoff response of suburban catchments, and that they represent an effective and relatively low-cost option for urban watershed management and restoration.13 pagesen-USCC BY 4.0 DEED Attribution 4.0 Internationalhttps://creativecommons.org/licenses/by/4.0/deed.enText