Storm-water Monitoring Projects

1. Storm-water monitoring projects include efficiency studies on Best Management Practices (BMP's) for controlling urban runoff  as well as testing the effectiveness of management activities. Storm water studies are designed to quantify the ongoing efforts of Tahoe's jurisdictions in the capture and treatment of fine particles and other pollutants. In addition to quantifying existing conditions, studies are also aimed at fine-tuning existing treatment facilities and management activities, as well as providing data for the continued improvement of predictive models.

2. Examples of recent and ongoing projects:

The Tahoe City Wetlands Project - A cooperative effort between Placer County, TERC and DRI that has received funding from multiple agencies. This is one of the longest running stormwater monitoring projects in the Tahoe Basin. Data from this project has been used to understand ground to surface water interaction, residence times for pollutants in wet basins, pollution removal efficiencies, treatment capacities of various vegetation types, and the expected life span of such a system.

Road Abrasive and Wash-off Study- A cooperative study between El Dorado County, TERC, and Texas Southern University. Funding comes from the USFS SNPLA program. This project aims to quantify the effectiveness of management practices related to road maintenance and help in the selection of low impact road abrasives.

The effect of the first flush, the process whereby most of the pollutants are mobilized in the very early stages of a storm, is evident here, with five times the sediment being transported at the beginning of the storm.

Implementer's Monitoring Plan

A cooperative effort between both California and Nevada jurisdictions. This is orchestrated by the Tahoe Resource Conservation District (TRCD) and aims to assist with TMDL monitoring. Funding comes from Proposition 84 funds.

Urban stormwater being discharge directly to the lake via a culvert at the end of Pasadena Ave. (South Lake Tahoe). Our research is directed at preventing this from occurring. Photo: R. Townsend

Field Testing Existing Stormwater Facility Effectiveness in Fine Particle Removal

This project was part of Adrienne Aiona’s MS thesis research. Results of this two year monitoring program showed that a detention basin could reduce fine particle concentrations by a factor of four.

Cattleman’s Detention Basin. Photo: A. Aiona

The Role of Vegetation

Vegetated floodplains and wetlands trap particulates, a process which is important for water quality and wetland form and function. Kristen Fauria’s MS thesis research entailed a series of laboratory flume experiments with synthetic grasses that evaluated particle removal rates for a range of particle sizes and experimental treatments. The presence of vegetation was found to increase the rate of particle capture/decay compared to a bare flume. Particle capture by plants increased with particle size, the presence of biofilm, and stem density.

Synthetic plants in the experimental flume after an experiment. Photo: K. Flauria

monitoring ward creek

Monitoring Ward Creek during a storm in 2010