Antidegradation

Antidegradation is a tool that states use in meeting the Clean Water Act (CWA) requirement that water quality standards protect the public health and welfare, enhance the quality of water, and meet the objective of the Act to “restore and maintain the chemical, physical and biological integrity” of United States' waters. The EPA's regulation requires that states adopt antidegradation policies and identify implementation methods to provide three levels (tiers) of water quality protection to maintain and protect

The first antidegradation policy statement was released in 1968, by the Secretary of the U.S. Department of the Interior. It was included in EPA's first Water Quality Standards Regulation (40 CFR 130.17, 40 F.R. 55340 - 41, November 28, 1975).

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