Bennettsen Lake Dam, located in Mason, Washington, is a state-owned structure that serves the primary purpose of recreation. Completed in 1971, this earth dam stands at a hydraulic height of 11 feet, with a structural height of 6 feet and a length of 150 feet. The dam has a storage capacity of 270 acre-feet, with a normal storage level of 253 acre-feet, covering a surface area of 28 acres and draining a small watershed of 0.18 square miles.

Situated on the Tr-Tahuya River, the Bennettsen Lake Dam poses a low hazard potential and is not currently rated for its condition. Although last inspected in June 2001, the dam is regulated and inspected by the Washington Department of Ecology, ensuring compliance with state safety and maintenance standards. Despite its low risk profile, the dam lacks an Emergency Action Plan (EAP) and other risk management measures, highlighting the need for continued monitoring and preparedness in the face of potential climate-related challenges.

With its picturesque location and recreational opportunities, Bennettsen Lake Dam stands as a vital water resource for the community, offering a serene setting for outdoor activities. As climate change impacts water resources across the region, the maintenance and safety of dams like Bennettsen Lake become increasingly important in ensuring the resilience of water infrastructure and the protection of surrounding ecosystems.