Found a website that tracks municipal drinking water quality by zip code or state.  
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The United States of America annually produces millions of tons of pollution and spends tens of billions of dollars per year controlling this pollution. 

Water pollution law is extraordinarily complex. It can involve areas of common law such as nuisance, trespass, and negligence, but more often it involves an interconnected network of federal and state statutes and regulations, the cornerstone of which is the Clean Water Act (CWA).

The Clean Water Act (CWA) established the basic structure for regulating discharges of pollutants into the waters of the United States and regulating quality standards for surface waters. The basis of the CWA was enacted in 1948 and was called the Federal Water Pollution Control Act.  The Act was significantly reorganized and expanded in 1972. "Clean Water Act" became the Act's common name with amendments in 1972.