West Virginia National Guard Ridge Runner exercise participants prepare to exit a UH-60 Blackhawk above Tygart Lake during a military-operations rehearsal in Grafton, West Virginia, July 16, 2025. Authorized by the Rivers and Harbors Act of 1935, Tygart Dam was the first of 16 flood-control projects constructed in the U.S. Army Corps of Engineers Pittsburgh District. The dam provides flood protection for the Tygart River Valley and for the Monongahela and upper Ohio rivers, and has prevented more than $1.3 billion in flood damages since its construction in 1938. In addition to flood control, Tygart Dam is authorized for to support river navigation and water supply missions. During the summer and fall low-water season, Tygart Dam releases additional water downstream to meet navigation water supply requirements on the Monongahela and upper Ohio rivers. The increased flow also improves water quality and quantity for domestic and industrial use, recreation, and aquatic life. (U.S. Army Corps of Engineers photo by Andrew Byrne)