Federal Water Pollution Control Act, establishes a national program to restore and maintain the quality of the nation's waters. Point sources of pollution are regulated under the Act while state programs for nonpoint sources are subject to federal funding and technical assistance.

The CWA authorized states to establish water quality standards, subject to federal review and approval, to protect public health or welfare and improve the quality of the water. These standards are translated into permit limits, which are issued to municipal and industrial dischargers. Under the CWA, discharges to waters of the United States are illegal without these permits, which ensure that the wastewater discharges present no risk to human health and the environment. 

Reproduced courtesy from the Association of Metropolitan Sewerage Agencies (AMSA) - www.amsa-cleanwater.org. The Cost of Clean is also available on AMSA's web site or by contacting AMSA's National Office at (202) 833-AMSA.