Clean Water Act 303(d) List | Region 10 | US EPA

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Clean Water Act 303(d) List of Impaired Waters

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Under section 303(d) of the 1972 Clean Water Act, states, territories, and authorized tribes are required to develop lists of impaired waters. These impaired waters do not meet water quality standards that states, territories, and authorized tribes have set for them, even after point sources of pollution have installed the minimum required levels of pollution control technology. The law requires that these jurisdictions establish priority rankings for waters on the lists and develop TMDLs for these waters.



Assessment and Listing of Impaired Waters in AK, ID, OR, WA




EPA 303(d) and TMDL Guidance and Regulations


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URL: http://yosemite.epa.gov/R10/WATER.NSF/TMDLs/CWA+303d+List

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