This report discusses key drinking water issues in the 109th Congress, which have included problems caused by specific contaminants, such as methyl tertiary butyl ether (MTBE) and perchlorate, as well as the related issue of the appropriate federal role in providing financial assistance for water infrastructure projects. Congress last reauthorized the Safe Drinking Water Act (SDWA) in 1996, and although funding authority for most SDWA programs expired in FY2003, broad reauthorization bills have not been proposed, as the Environmental Protection Agency (EPA), states, and water systems remain busy implementing the 1996 amendments.