National Dam Safety Program. Cockram Mill Dam (Inventory Number VA 14105), Roanoke River Basin, Patrick County, Virginia. Phase I Inspection Report.

The dam is classified as a small size dam with a significant hazard classification. The spillway consists concrete rectangular notch 1.4 feet deep and 85 feet long across the center portion of the dam. The reservoir is used for recreation and limited grist mill operation. 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. The spillway will pass 3 percent of the PMF or about 10 percent of the SDF without overtopping the dam. The SDF will overtop the dam by a maximum 2.86 feet, reach an average critical velocity of 8.0 feet per second (fps) and flow over the dam for 7 hours. The spillway is adjudged inadequate but not seriously inadequate.