Total Maximum Daily Loads (TMDLs) and the 303(d) List of Impaired Water Bodies

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Click to see The 303(d) List  page
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Total Maximum Daily Loads (TMDLs) are action plans to restore clean water. Section 303(d) of the federal Clean Water Act requires that states identify water bodies -- bays, rivers, streams, creeks, and coastal areas -- that do not meet water quality standards, and the pollutants that impair them. TMDLs examine the water quality problems, identify sources of pollutants, and specify actions that create solutions. They are adopted by the Regional Water Board as amendments to our Region's Basin Plan.
More information about TMDLs

Within our region, the 2010 303(d) list includes more than 270 listings in 88 water bodies. Water Board staff are currently developing TMDL projects to address more than 160 of these listings. (One TMDL may address multiple listings. For example, the Diazinon/Pesticide Toxicity TMDL for urban creeks addressed more than 30 impaired creeks or creek segments.)


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