Optimization of Stormwater Filtration at the Urban/Watershed Interface

Tom Miles

Optimization of Stormwater Filtration at the Urban/Watershed Interface
Hipp, J. A.; Ogunseitan, O. A.; Lejano, R.; Smith, C. S.
Urban Water Research Center, UC Irvine, CA www.uwrc.uci.edu

Tests of charcoal in polybags for storm water filtration.

Environmental pollution from cities is a major ecological problem attributed to contaminated runoff from nonpoint sources. The U.S. Environmental Protection Agency's guidance on implementation of total maximum daily loads (TMDL) does not adequately cover methods to improve waters impaired by nonpoint sources. To comply with TMDLs, cities may install filters in curb inlets, or use other Best Management Practices (BMPs). We tested 10 different filters and found their effectiveness in retaining pollutants ranged from 0 to >90%, depending on combinations of pollutant types (metals, pathogens, and total suspended sediments (TSS)) and filter materials. Hence, the decision to deploy filters into curb inlets must consider land use patterns associated with specific categories of pollutants generated within cities. We developed a geographic information system (GIS)-enabled model for estimating and mitigating emissions of pollutants from urban regions into watersheds. The model uses land use categories and pollutant loadings to optimize strategic placement of filters to accommodate TMDLs. For example, in a city where the landuse pattern generates 4