Lac Vieux Desert, located in Vilas, Wisconsin, is a hydroelectric dam with a primary purpose of flood risk reduction, hydroelectric power generation, and recreation. Completed in 1870, this gravity dam stands at 7 feet high and is supported by stone foundations. With a storage capacity of 20,000 acre-feet and a surface area of 5,066 acres, Lac Vieux Desert plays a crucial role in managing water resources in the area.

Managed by the Federal Energy Regulatory Commission, Lac Vieux Desert has a significant hazard potential and a very high risk assessment rating. The dam features a controlled spillway and Tainter (radial) outlet gates, ensuring the safe release of water during high discharge events. Despite being in operation for over a century, the dam's condition assessment is currently not rated, emphasizing the importance of regular inspections and maintenance to ensure its continued safety and effectiveness for both water management and hydroelectric power generation.

As a key structure in the region, Lac Vieux Desert serves as a vital resource for the community, providing essential flood control measures, renewable energy production, and recreational opportunities. Its location on the Wisconsin River, along with its historical significance and engineering design, make it a notable site for water resource and climate enthusiasts to study and appreciate the intersection of human infrastructure with natural landscapes.