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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Tahoe Stormwater Particle Assessment and Management for Urban and Roadway Runoff

Proposal [pdf]

Lead Researchers:

Alan Heyvaert and Jim Thomas, Desert Research Institute, John Reuter, University of California, Davis


The urban portion of the watershed contributes about 70% of the fine sediment that is delivered to Lake Tahoe. These fine particles significantly affect water clarity in this otherwise pristine lake. Current pollutant reduction strategies are targeting their removal through erosion control and stormwater treatment projects. The investment of significant financial resources to improve the Lake's clarity requires that our understanding of the sources, transport and potential for removal of these particles from urban stormwater be accelerated. The intent of this project is to add to our current, yet incomplete knowledge concerning fine particles. Specifically, this project will (1) provide information to help establish reliable, calibrated relationship(s) between turbidity, the mass of size-fractionated suspended solids, and the number of <16 micron particles in stormwater runoff; (2) provide details on mechanisms involved in the removal of fine particles in vegetated BMP treatment basins; and (3) provide data on the efficiency of this commonly used BMP type, while also giving recommendations for design characteristics to increase fine particle removal. The Lake Tahoe TMDL (Total Maximum Daily Load) program and associated efforts to improve lake clarity (e.g. Environmental Improvement Program) will greatly benefit from this increased understanding of fine sediment removal and how to measure success.

Relation to Other SNPLMA Projects

This project will build upon information developed from the SNPLMA Round 7 and 8 science projects: "Tahoe Basin Particle Size Analysis and Protocol Development" and "Determining Sources of Highway Runoff Fine Sediment in Stormwater, Streams, and Lake Tahoe Using Fingerprinting Techniques," which when completed next year will provide new information on laser- and optical based measurement techniques and on the relative contribution of fine particles from traction material, road abrasion, vehicles, road cut and shoulder erosion of parent material. It will also support and be supported by the SNPLMA Round 9 science project, "Priority urban stormwater monitoring to directly inform the Pollutant Load Reduction Model (PLRM)".

Expected date of final products:

December 2014

Last Modified: Aug 29, 2016 09:48:33 AM