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Water Quality Standards Regulations: Maine

Presented below are water quality standards for the state of Maine in effect for Clean Water Act (CWA) purposes.

EPA is posting these standards as a convenience to users and has made a reasonable effort to assure their accuracy.

Documents marked with an asterisk (*) are not part of the official Maine CWA-WQS docket and therefore not subject to review under the Clean Water Act.

On this page:

State Standards in Effect for CWA Purposes

Since 2015, EPA has taken several actions on Maine’s WQS.  Please refer to EPA’s action letters below for more information.

The following statutes are from the Maine Revised Statutes, Title 38, Chapter 3, Subchapter 1: Environmental Protection Board.

Article 1: Organization and General Provisions

Article 1-F: Nonpoint Source Pollution Program

Article 2: Pollution Control

Article 3: Enforcement

Article 4-A: Water Classification Program

The following statutes are from the Maine Revised Statutes, Title 38, Chapter 5, Subchapter 1: Mills and Dams:


[See Letter from Maine DEP to U.S. EPA clarifying provisions of Maine water quality standards related to dam impoundments ]

Federally Proposed or Promulgated Standards

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