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.

EPA's 303(d) Program in Region 9

• Arizona
• California
• Hawaii
• Nevada
• American Samoa, Commonwealth of Northern Mariana Islands and Guam

State Programs in Region 9

• Arizona Department of Environmental Quality (AZDEQ)
  • 303(d) List
  • TMDLs
• California State Water Resources Control Board
• California Water Quality Monitoring Council
• Hawaii Department of Health
• Nevada Division of Environmental Protection (NDEP)
• American Samoa Environmental Protection Agency
• Commonwealth of Northern Marianas Islands (CNMI) Bureau of Environmental and Coastal Quality
• Guam Environmental Protection Agency