Loutsis Dam, located in Duvall, Washington, is a private-owned structure regulated by the Washington Department of Ecology. Built in 1970, this earth dam stands at a hydraulic height of 22 feet and a structural height of 18 feet, with a length of 395 feet. The dam's primary purpose is for recreation, but it also serves irrigation needs in the area.

With a storage capacity of 138 acre-feet, Loutsis Dam plays a crucial role in water resource management in the region, providing a normal storage capacity of 97 acre-feet. The dam's hazard potential is classified as low, with a satisfactory condition assessment as of 2000. The structure is regularly inspected by the state regulatory agency to ensure its safety and functionality.

Despite its modest size, Loutsis Dam serves as a vital water management tool for the local community, offering recreational opportunities and supporting irrigation activities. Its presence along the Tr-Snoqualmie River highlights the importance of sustainable infrastructure for water resource management in Washington State.