The Effects of Climate Change on Lake Tahoe, and Implications for Design of Best Management Practices. For the USDA Forest Service, with funding from the Southern Nevada Public Lands Management Act., 2008-2010. Through UC Davis, Coats is Co-Principle Investigator on a project that aims to use the output of two climate models as input to both a distributed hydrologic model for the Tahoe Basin, and a lake clarity model. Output from the hydrology model will also be used as input the lake model. As separate model will be used to evaluate how climate change will affect the design requirements for water quality BMPs in the Basin.

The Warming of Lake Tahoe. For the Tahoe Research Center, University of California at Davis, 2002-2004. In a study on the impacts of climate change on Lake Tahoe, Hydroikos analyzed a 33-yr record of water temperature, and related changes in lake temperature to climatic variables using Principal Components Analysis. A co-author on the project at UC Davis then applied a lake hydrodynamic model to show that the observed changes in air temperature and downward long-wave radiation can reasonably explain the upward trend in lake temperature and thermal stability.

Link to San Francisco Chronicle article Download PDF article in Climatic Change

Bob Coats, holding a reversing thermometer that is used to measure deep water temperatures in Lake Tahoe. One of the UC Davis instrument buoys is in the background.

Water Management Study for Shoreline Sailing Lake. For the City of Mountain View, 2001. The City of Mountain View operates a 57 ac recreational lake at Shoreline, which is provided with water from Charleston Slough. Hydroikos is analyzing the water quality problems and water supply issues for the City. The project includes measuring suspended sediment concentrations and tide heights using sensors and data loggers, hydrodynamic modeling of circulation and sedimentation in both Charleston Slough and the Sailing Lake, a lake nitrogen budget and other water quality studies, assessment of the biota of the lake, analysis of operational alternatives for the water supply system, and report presentation.

Thermal Structure and Water Quality at Jenkinson Lake. For the El Dorado Irrigation District, 2004-2005. Jenkinson Lake, near Sly Park in El Dorado County, is an important water supply lake that provides drinking water for Placerville and other nearby communities. It is also an important recreational asset during summer months for foothill and valley residents. To allow continued body contact recreation, the California Department of Health Services required a showing that there is no risk to public health from bacteria and protozoans that could be released by swimmers. Hydroikos sampled the lake and inflowing streams for Giardia, Cryptosporidium, Enterococcus and Coliform bacteria, and measured changes in the lake's thermal structure during a year-long study. The results have been used in models run by the firm Hydrologic Systems and by an investigator at UC Riverside, and have helped to show that swimming may continue at the lake without risk to public health.

Water Management Plan for Aquatic Park. For the City of Berkeley, 2002-2003. Aquatic Park is a partially-tidal lagoon connected to San Francisco Bay by a series of culverts and tide gates. The City is planning to upgrade the Park and improve water quality by enhancing tidal exchange and internal circulation. Hydroikos measured and modeled the existing tidal regime and modeled the effects of enhancement alternatives on tidal exchange with the bay.