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  1. Home
  2. Water Quality Standards: Regulations and Resources

Federal Water Quality Standards Requirements

The Water Quality Standards Regulation (40 CFR 131) establishes the requirements for states and tribes to review, revise and adopt water quality standards. It also establishes the procedures for EPA to review, approve, disapprove and promulgate water quality standards pursuant to section 303 (c) of the Clean Water Act.

  • Final Rulemaking to Update the National Water Quality Standards Regulation (August 21, 2015)
On this page:
  • Review and Approval of State and Tribal Water Quality Standards
  • Federal Guidance for Standards in the Great Lakes System

Review and Approval of State and Tribal Water Quality Standards, "Alaska Rule" (Effective May 30, 2000)

We require that water quality standards adopted by states and authorized tribes on or after May 30, 2000 must be approved by EPA before they can be used as the basis for actions, such as establishing water quality-based effluent limitations or total maximum daily loads (TMDLs), under the Clean Water Act.
  • 40 CFR 131.21
  • Fact Sheet: EPA Review and Approval of State and Tribal Water Quality Standards (pdf) (101 KB, April 2000, EPA 823-F-00-006)
  • Federal Register Notice (April 27, 2000)
  • Memo from Geoff Grubbs: Questions and Answers on EPA’s “Alaska Rule” (pdf) (183.46 KB, 9/15/2000)

Federal Guidance for Standards in the Great Lakes System

The Water Quality Guidance for the Great Lakes System was issued in 1995.  It established minimum standards, antidegradation policies, and implementation procedures for waters of the Great Lakes system. This includes special requirements for bioaccumulative chemicals of concern. The eight Great Lakes states were required to adopt water quality standards as protective as these requirements within two years (by 1997).

  • Water Quality Guidance for the Great Lakes System: 40 CFR Part 132

Water Quality Standards: Regulations and Resources

  • What are Water Quality Standards?
  • Federal WQS Requirements
  • Standards in Your Area
  • Federally Promulgated WQS for Specific States, Territories, and Tribes
  • Tribes and Water Quality Standards
    • EPA Actions on Tribal WQS and Contacts
  • WQS Handbook
  • Reference Library of WQS Policy and Guidance Documents
  • WQS Academy
Contact Us: Standards for Water Body Health - Regulations and Resources
Contact Us to ask a question, provide feedback, or report a problem.
Last updated on April 15, 2025
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