Water Board Resolution No. R6T-2006-0017, adopted on April 13, 2006 by the Lahontan Regional Water Quality Control Board, modified the Water Quality Control Plan for the Lahontan Region by establishing a Total Maximum Daily Load (TMDL) to control sediment in Squaw Creek, Placer County.
The TMDL sets numeric targets which include physical habitat measures of stream substrate quality (median particle size and percent fines and sand), and biological parameters that represent desired stream habitat conditions for fish and aquatic invertebrates. The TMDL focuses on controlling sources of sediment from land use categories identified as major contributors to excessive in-stream sediment loading. Based on comparison with reference streams, it is estimated that a 50 percent reduction in the controllable sediment loading of 21,800 tons per year (from the level estimated as of 2001) is needed to protect beneficial uses. The TMDL implementation program is based on continuation and improvement of existing erosion control and monitoring programs conducted by current permitted discharges. Other individual or general permits will be issued as warranted for construction-related or other land-disturbing activities to control sediment discharges to Squaw Creek.
Implementation monitoring will center on tracking compliance with existing and proposed regulatory actions, including installation and maintenance of Best Management Practices to control sediment discharges, with a focus on control of fine sediment. Progress toward meeting the TMDL will be determined through monitoring of the in-stream physical and biological parameters. The estimated time frame for meeting the numeric targets and achieving the TMDL is 20 years. This estimate takes into consideration the time needed for dischargers to identify sediment sources, to devise a plan to address those sources, and to fully implement appropriate sediment controls; and for target indicators to respond to decreased sediment loading. The Lahontan Water Board has committed to reviewing the TMDL after 10 years to determine if revisions are warranted based on relevant compliance data.
Cal. Code Regs. Tit. 23, § 3959