The Pasadena monitoring site is located at the northern most end of Pasadena Avenue in the City of South Lake Tahoe. A 36-inch pipe emerges from the side of the steep slope at the end of Pasadena Avenue and conveys runoff directly to Lake Tahoe. There are two monitoring stations at this site, the first at the inflow to a series of two parallel Contech Stormfilter vaults (“Stormfilter”) and the second at the outflow from the vaults. Effluent pollutant loads will be compared to influent pollutant loads to assess how well the Stormfilter reduces pollutant loads. Monitoring data will also be used to determine maintenance intervals.

An environmental improvement project completed in 2010 made several improvements in the catchment, including the installation of 9,694 square feet of permeable pavement on the shoulders of six blocks of residential streets and 3,891 linear feet of perforated storm drain pipes to increase in-situ infiltration wherever feasible throughout the project area. The permeable pavement was an attempt to maximize infiltration and stabilize road shoulders while providing parking and unimpeded snow removal on a stable surface, a challenge that California jurisdictions have been struggling with in their project designs for more than twenty years.

This outfall was the former Regan Beach TMDL monitoring site, one of 19 sites in the Tahoe Basin equipped with auto-samplers and monitored during 2003 and 2004 by the University of California, Davis, Tahoe Environmental Research Center (UCD TERC) and the Desert Research Institute (DRI) as part of the Lake Tahoe TMDL research effort. Data collected at this site was used to establish Event Mean Concentrations for residential land-use categories that ultimately populated the Pollutant Load Reduction Model (PLRM). In addition, this catchment was monitored for flow and turbidity by 2NDNATURE from March 2012 to February 2013. The data collected by the Tahoe RCD is continuing the long-term data set for this site and can be used to evaluate how effective the environmental improvement project was at reducing runoff volumes and pollutant loads to Lake Tahoe.