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Colorado River Basin - TMDL Program

Total Maximum Daily Load (TMDL) and the 303(d) List of Impaired Water Bodies

The Total Maximum Daily Load (TMDL) Unit in the California Regional Water Quality Control Board, Colorado River Basin Region (Regional Water Board 7 or Region 7) manages the regional TMDL Program. The TMDL Program updates Clean Water Act (CWA), Section 303(d) List of impaired surface waters in need of TMDLs, and develops and implements priority TMDLs throughout the Region.

Questions or Comments about TMDL and 303(d) List?