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Impaired Waters and TMDLs

Impaired Waters and TMDLs in the Pacific Southwest (Region 9)

Serving Arizona, California, Hawaii, Nevada, Pacific Islands, 148 Tribal Nations

States and territories in EPA's Pacific Southwest (Region 9) maintain programs that conduct water quality monitoring, develop assessment reports, and develop TMDLs for impaired waters. More information about individual State and Territory programs can be found below.