Effectiveness of Retrofitting Low Impact Development in Parking Lots to Reduce Flooding

Document Type

Conference Proceeding

Publication Date


Publication Title

World Environmental and Water Resources Congress 2020


American Society of Civil Engineers

Publisher Location

Henderson, NV

First page number:


Last page number:



Urban flooding is a manmade disaster and a recurrent problem in cities. Flooding can be reduced by increasing land surface perviousness and reducing connectivity between impervious surfaces. This research compares the effectiveness of five low impact development retrofitting options for flood remediation in a parking lot including porous asphalt, gravel and grass swale strips, grass pavers, and concrete grid pavers. Digital elevation model (DEM), land cover, and hydrologic soil group data are used to develop watershed model in a geographic information system (GIS)-based framework. This framework is capable of watershed delineation from DEM, runoff generation and routing, and inundation mapping. Soil conservation service (SCS) curve number method is used to estimate discharge hydrograph and GIS spatial analyst is used to map inundation. Due to a lack of observed discharge data, calibration is performed over data resolutions and drain inlet clogging factor utilizing flood information from news reports, photographic evidence, and observed watermark of inundation extent. The change in flooding for the five remediation measures is simulated for Blacklot parking area at the University of Nevada Las Vegas campus. The results show that the watershed flooding reduces with a decrease in curve number of the surface. Flooding is reduced by 26% for porous asphalt, and only 2.9% for grass and gravel swale strips. The flooding is significantly reduced for grass pavers (46%), while flooding was completely prevented by concrete grid pavers. This research reveals that concrete grid pavers are an effective option to avoid flooding in Blacklot area. This study provides a useful insight about low impact development retrofitting in parking lots to reduce urban flooding.


Environmental Engineering | Water Resource Management



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