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The Department of Environmental Quality is committed to helping citizens of the Commonwealth to lower their water usage and conserve the natural resources of our area. They have lots of great information regarding conservation and water usage.
http://www.deq.state.va.us/water

The Upper Tennessee River Roundtable is a non-profit organization with an overall interest in improving water quality in the Upper Tennessee River Watershed. Don't let the name confuse you: the Upper Tennessee River Roundtable is based in Southwest Virginia.
http://www.uppertnriver.org