Water quality impairments, come in the form of pollution discharged to streams or the destruction of aquatic life habitat. Sedimentation, excess nutrients, and bacteria most commonly impair rivers and streams, according to the U.S. Environmental Protection Agency's (EPA) national survey of water quality, which was reported to Congress last year. Before the Clean Water Act (CWA), pollution problems were most often associated with "point sources," discharges from heavy industrial facilities and sewage treatment plants.

But after almost 30 years of CWA implementation, pollution from these sources is under control. Now, new water quality challenges confront the country. For instance, municipal and industrial stormwater runoff and concentrated animal feeding operations must now meet tough new standards. And in the future, federal, state, and local governments will be turning their attention to difficult-to-control "nonpoint source" water pollution in urban and rural areas caused by runoff from city streets, agricultural fields, timber harvests, road building, pastures or runoff from other rural lands.

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.