POLLUTION LOCATOR|Regulatory Coverage: Clean Water Act Priority Pollutants

The federal Clean Water Act (CWA) focuses on 126 chemicals that were designated as "priority pollutants" in 1977. Although many other toxic chemicals are also being released to water, the Clean Water Act does not cover them, despite its name.

The 126 priority pollutants can be subject to several different kinds of regulatory activity, some based on considerations of water quality and some based on the technologies available for pollution control in different industrial sectors. The Environmental Protection Agency establishes criteria for the quality of ambient water (lakes and streams, for example) that identify the concentration levels of specific chemicals that will not pose unacceptable risks to human or aquatic life. These criteria are not enforceable legal standards. However, they can serve as the scientific foundation of water quality standards set by states, which are enforceable. Separately, U.S. EPA also sets limits on the discharge of priority pollutants ("effluent limits") by various types of industries. These limits are generally based on the "best available technology economically achievable" for controlling discharges. Such technology may or may not succeed in keeping discharges below levels that adversely affect water quality.

See a list of the chemicals covered by the Clean Water Act (CWA)

More information about the Clean Water Act: