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Tribes and Water Quality Standards

Water quality standards (WQS) provide the regulatory and scientific foundation for protecting water quality under the Clean Water Act (CWA). WQS not only set water quality goals for a tribe’s water bodies, but also serve as the regulatory basis for establishing water quality-based treatment controls and strategies. To administer a WQS program under the CWA, a tribe must apply to EPA for authorization to be treated in a similar manner as a state (TAS) (refer to the second tab above). To learn more about WQS and coverage in Indian country, please refer to the resources below.

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Treatment in a Similar Manner as States (TAS)

Clean Water Act (CWA) Section 518(e) expressly provides for Indian tribes to play essentially the same role in Indian country that states do within state lands, authorizing EPA to treat eligible federally recognized Indian tribes in a similar manner as a state (TAS) for implementing and managing certain environmental programs.

Eligible TAS tribes may implement and manage certain CWA programs including the following: A tribe may be found eligible to run one or more of these programs if it can demonstrate...
  • it is federally recognized;
  • it has a governing body carrying out substantial governmental duties and powers;
  • it has appropriate authority; and 
  • it is (or will be) capable of carrying out the functions of the particular program.

In May 2016, EPA published a final rule revising the interpretation of the Congressional delegation of authority under CWA Section 518, streamlining the process for applying for TAS for CWA regulatory programs, including the water quality standards program.

To assist in the TAS application process to administer the 303(c) and 401 programs, EPA has provided the following streamlined TAS Application Template and other documents:

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Additional Information

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