Abstract |
The Garcia River watershed is a forested watershed located in northern California. The purpose of the Garcia River Total Maximum Daily Load (TMDL) is to identify loading allocations that, when implemented, are expected to result in the attainment of the applicable water quality standards for sediment. The Garcia River watershed was listed on Californias 1996 Clean Water Act (CWA) Section 303(d) list as water quality limited due to sedimentation. The level of sedimentation in the Garcia River watershed was judged to exceed the existing Water Quality Standards (WQS) necessary to protect the beneficial uses of the basin, particularly the cold water fishery. Accelerated erosion from land use practices and other causes is impacting the migration, spawning, reproduction, and early development of cold water fish such as coho salmon and steelhead trout. The TMDL includes: a problem assessment, which includes an assessment of existing instream and upslope conditions; identification of instream numeric targets, which are intended to interpret and apply the narrative water quality standards and also represent the optimum instream conditions for cold water fish; an assessment of significant sediment sources that have in the past or are presently impacting the stream system; a linkage analysis to determine the magnitude of reductions necessary to attain the numeric targets; an allocation of loads section, which identifies the loading capacity of the stream and individual load allocations for land use activities; and several other sections designed to address considerations set forth in Section 303(d) of the Clean Water Act or the implementing regulations at 40 CFR 130.7. The EPA has relied on the Garcia River Watershed Water Quality Attainment Strategy developed by the North Coast Regional Water Quality Control Board (December, 1997) for much of the information and analysis contained in this TMDL. |