The CWA is the main law regulating surface water quality in the U.S., but it does not cover groundwater or water quantity concerns. Some states have created their own standards for these things. The statute uses different regulatory and non-regulatory methods to reduce direct pollutant discharges into waterways greatly, set ambient water quality standards, finance municipal wastewater treatment facilities, and manage polluted runoff.
Restoration and maintenance of the chemical, physical, and biological integrity of our waterways is a major challenge, but necessary to ensure the protection and propagation of fish, shellfish, and wildlife, and the possibility of recreational activities in and on the water.
The original CWA was passed in 1948 under the name Federal Water Pollution Control Act, but it went through significant changes in 1972. The act became more commonly known as the Clean Water Act with amendments made in 1977.