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Water: Water Quality Standards

Water Quality Standards Review and Revision

[Why are WQS Important?] [WQS Review and Revision] [Role of the Public] [Designated Uses] [Water Quality Criteria] [Antidegradation] [General Policies] [Indian Tribe Participation] [WQS Program History]

The Clean Water Act requires States and authorized Indian Tribes to review their standards from time to time, but at least once every three years, and revise them if appropriate. Updates may be needed, for example, due to changing water quality conditions or water body uses or new scientific information on the effects of pollutants in the environment. In preparing proposed revisions to their standards, States and Tribes consider requests from industry, environmental groups, and the public, and review available information (e.g., CWA §305(b) reports, EPA guidance).

EPA has posted answers to frequently asked questions (FAQs) about determining whether a provision constitutes a new or revised water quality standard that EPA has the Clean Water Act Section 303(c)(3) authority and duty to approve or disapprove.

Each State and authorized Tribe has its own legal and administrative procedures for adopting water quality standards. In general, standards are adopted following a process in which draft revisions are developed (this may include a work group process or informal public meetings) and formally proposed for public comment. A public hearing is then held to receive input from the public regarding the proposal. The proposed water quality standards and supporting information are made available to the public prior to the hearing. States and Tribes are required to prepare a summary of the public comments received and how each comment was addressed.

Pursuant to revisions to the water quality standards regulation promulgated in April of 2000 (the "Alaska" rule), new or revised water quality standards become effective for purposes of the Clean Water Act upon EPA approval.

EPA approval of a new or revised water quality standard is considered a federal action which may be subject to the Section 7 consultation requirements of the Endangered Species Act (ESA). Section 7 of the ESA requires federal agencies to protect endangered species and threatened species and prohibits actions "likely to jeopardize the continued existence of any endangered species or threatened species or result in the destruction or adverse modification of habitat of such species which is determined to be critical…" Accordingly, consultation with the U.S. Fish and Wildlife Service is an important part of EPA's water quality standards approval process.

The Clean Water Act also authorizes EPA to promulgate superseding Federal water quality standards in cases where new or revised State or Tribal standards are not consistent with applicable requirements of the Act or in situations where the EPA Administrator determines that Federal standards are necessary to meet the requirements of the Act. EPA promulgation of water quality standards requires a rule making process and opportunity for public review and comment.


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