Lang Dam No 1 in Mount Vernon, Washington, is a privately owned earth dam completed in 1956 with a primary purpose of recreation. Located on Tr-Carpenter Creek, the dam has a hydraulic height of 13.25 feet and a structural height of 13.25 feet, providing a storage capacity of 21 acre-feet. The dam's normal storage capacity is 14.4 acre-feet, with a surface area of 30 acres and a drainage area of 0.43 square miles.

Despite its fair condition assessment and high hazard potential, Lang Dam No 1 is regulated by the Washington Department of Ecology, with state permitting, inspection, and enforcement in place. The dam is situated in Congressional District 02, represented by Rick Larsen (D), and falls under the jurisdiction of the Seattle District of the US Army Corps of Engineers. With a last inspection date in October 2020 and an inspection frequency of 5 years, Lang Dam No 1 remains a critical structure for fire protection, stock management, and small fish pond recreation in the region.

Water resource and climate enthusiasts will find Lang Dam No 1 an intriguing site for its historical significance, recreational opportunities, and environmental impact on the Tr-Carpenter Creek watershed. As a privately owned dam with state regulation and oversight, it serves as a reminder of the importance of proper maintenance and management of water infrastructure in ensuring public safety and ecological balance. With ongoing assessments and risk management measures in place, Lang Dam No 1 continues to play a vital role in the local community while offering a glimpse into the intersection of water resources, climate resilience, and regulatory practices.