Long Lake, located in Stevens County, Washington, is a privately owned reservoir with a primary purpose of hydroelectric power generation. Constructed in 1915 by Washington Water Power, this gravity dam stands at an impressive height of 213 feet, with a storage capacity of 105,080 acre-feet and a surface area of 5,060 acres. The reservoir is situated on the Spokane River, providing essential benefits for fish and wildlife, recreation, and hydroelectricity.

With a controlled spillway width of 353 feet and eight vertical lift outlet gates, Long Lake has a high hazard potential and a very high risk assessment rating. While it is not regulated by the state, the Federal Energy Regulatory Commission oversees its operation and inspections. Despite its age, the dam's condition assessment is currently not available, and there is no information on risk management measures in place. With its picturesque location and vital role in providing renewable energy and water resources, Long Lake is a fascinating site for enthusiasts of water resources and climate.