STORET is a water quality database maintained by the U.S. Environmental Protection Agency (EPA). STORET contains raw biological, chemical, and physical data on surface and ground water collected by federal, state and local agencies, Indian Tribes, volunteer groups, academics, and others. STORET is web-enabled and available to the public. You can view STORET with a standard web browser. You can also create files to be downloaded to your computer.

http://www.epa.gov/storet/about.html