Which US federal law regulates surface water quality?

The Clean Water Act (CWA) is the primary federal law in the United States that regulates surface water quality. Enacted in 1972, the CWA aims to restore and maintain the integrity of the nation's waters by preventing point and nonpoint source pollution, regulating discharges of pollutants, and setting water quality standards for surface waters. It establishes the National Pollutant Discharge Elimination System (NPDES), which requires permits for point sources that discharge pollutants into navigable waters.

This legislation has played a crucial role in improving water quality across the country, addressing issues such as municipal wastewater treatment, industrial discharges, and stormwater runoff. The CWA emphasizes the importance of maintaining water quality for various uses, including recreational activities, habitat for aquatic life, and drinking water supplies.

While other laws like the Rivers and Harbors Act, the Water Pollution Prevention Act, and the Toxic Substances Control Act address related environmental concerns, they do not specifically focus on the management and regulation of surface water quality to the same extent as the Clean Water Act.