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Pacific Southwest, Region 9

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

Water Quality Standards

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Water quality standards serve as the foundation for the water-quality based approach to pollution control. Water quality standards are state or tribal requirements that define the water quality goals of a lake, stream, or other waterbody by designating the beneficial uses and setting criteria to protect those uses. Beneficial uses may include fishing, swimming, boating, aquatic habitat, agriculture navigation, or others.

Water quality criteria establish standards necessary to protect and ensure that beneficial uses are attained. Criteria may be numeric or narrative standards that are designed to restore and maintain the chemical, physical, and biological integrity of a waterbody.

Programs & Resources

Resources for Tribal Government

Additional Resources

Region 9 Standards

State, Tribal, Territory Programs Approved water quality programs in Region 9

Activities Related to Water Quality Standards

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