The Clean Water Act (CWA) is a far-reaching statute enacted originally in 1948 as the Water Pollution Act. In 1972, with a broad mandate and bipartisan support, the CWA was established as a national priority to end the discharge of pollutants to waterways. The CWA was amended many times and continues to be amended almost yearly due to scientific, political and policy concerns. Rivers and lakes in the United States continue to have water quality problems; however, there has been much improvement in the last 30 years and the CWA has been a central part of this process. The CWA 30th anniversary activities last year focused on influencing public opinion by raising the awareness of water policy issues and reminding the public that water cannot be taken for granted. Changes in funding arrangements, emerging nonpoint source pollution issues, effluent trading controversies, and citizen suits are all primed to encourage interaction between science, politics and clean water policies. This paper looks at the future of this landmark legislation and the challenges it faces as it completes its 30th year in existence. Includes 26 references, table.