A team of experts from Tetra Tech, Inc., an environmental consulting firm, is developing the model under the direction of the Lahontan Regional Water Quality Control Board (Lahontan).  The basis of the model is the U.S. Environmental Protection Agency's watershed modeling system.  The system includes mathematical equations for simulating watershed hydrology, erosion, water quality processes, and in-stream transport processes. 

Outputs Support the TMDL

The Watershed Model is a complex system that will use information from studies underway to support the Total Maximum Daily Load (TMDL) process; historical data; and outputs generated from two models: the Stream Channel Erosion model and the BMP Effectiveness Model.  Together, these data will provide an accurate picture of the Lake Tahoe terrestrial watershed and its processes.

The Watershed Model is a critical component of developing the final Technical TMDL for Lake Tahoe.  The outputs from the Watershed Model will be linked to the Lake Tahoe Water Clarity Model.  The data and answers generated by these two models will provide a solid, scientifically based and defensible foundation to develop the Lake Tahoe TMDL.  The model will be housed at Lahontan.

 More information

For more detailed information about the Lake Tahoe Watershed Model, refer to the Winter 2002-2003 edition of the: Lake Tahoe Nutrient and Sediment Total Maximum Daily Load Newsletter

For additional information about the TMDL process and the models being developed to calculate the TMDL, contact the Lahontan Regional Water Quality Control Board, at (530) 542-5469.