USDA Forest Service

Pacific Southwest Research Station

Pacific Southwest
Research Station

800 Buchanan Street
Albany, CA 94710-0011
(510) 883-8830
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Measuring the ability of floodplains to treat urban runoff in the Lake Tahoe basin

Principal Investigators:
Geoff Schladow, University of California-Davis
Stefan Wuertz, University of California-Davis

Proposal [pdf]

Final Report [pdf]

Please contact Dr. Geoff Schladow with questions regarding the final report.

Project Summary

This study measured the ability of a stormwater detention basin and associated floodplain to remove sediment from stormwater runoff. The primary constituents measured were flow, total suspended solids (TSS), the inorganic fraction of TSS, fine particle concentration (FSP) for particles ≤16 μm, and turbidity. Fine particles are the primary pollutant of concern for the Lake Tahoe Basin because they decrease the optical clarity of the lake.

The study was performed at Cattlemans detention basin, a constructed stormwater facility, in South Lake Tahoe, CA. The basin is successfully removing fine particles from stormwater runoff. Extrapolating from the data collected, the basin is estimated to remove a total of 4.4 x 1016 particles annually—a little over 2% of the reductions El Dorado County is required to meet in the Lake Tahoe Total Maximum Daily Load (Lahontan Regional Water Quality Control Board [LRWQCB] and Nevada Division of Environmental Protection [NDEP] 2010). Considering this facility is only treating an 11.2-acre drainage basin, this is a significant amount of removal.