Chatfield Reservoir and dam on the South Platte River south of Littleton, Colorado were built by the United States Army Corps of Engineers as a response to the disastrous flood of 1965. In addition to its primary purpose of flood control, it serves as one of many water supply reservoirs for the city of Denver, Colorado. In 1966, the U.S. Atomic Energy Commission projected a total federal cost of $74 million. Construction of the project was begun in 1967 and the dam was completed in 1975.