National Dam Safety Program. Warrenton Dam (Inventory Number VA 06101), Potomac River Basin, Fauquier County, Virginia. Phase I Inspection Report.

Warrenton Dam is comprised of a 550 foot long concrete slab and buttress dam and two earthen dikes separated by a grassy knoll. The dikes are in the reservoir located in a low lying area north of the dam. One dike is about 300 feet long and 13 feet high. The other dike, perpendicular to the first, is about 175 feet long and 6 feet high. A concrete intake structure comprised of three 8-inch intakes at different elevations allows flow to discharge into the stream below the dam, furnishing water to the Warrenton Filtration Plant about 2 miles downstream. The concrete intake structure also has a 24-inch inlet and a 24-inch outlet. The maximum height is 30.8 feet for the concrete spillway. The dam is located 0.5 miles north of the Warrenton town limits and is used as the water supply for Warrenton, Virginia. The dam is owned and maintained by the Town of Warrenton, Virginia. The dam is classified as a small dam with a significant hazard classification. Based on criteria established by the Department of the Army Office of the Chief of Engineers (OCE), the Spillway Design Flood (SDF) is the 100 year flood. Since the spillway was sized for the 21 percent PMF, which is greater than the 100 year flood, the spillway is adjudged as adequate.