Long Branch State Park occupies 1,828 acres around Long Branch Lake in northern Missouri, west of Macon. The park and reservoir grew from decades of efforts to reduce chronic flooding along the Little Chariton River, which persisted despite earlier channelization work. Congress authorized Long Branch Dam in 1965 for flood control, water supply, recreation, water quality, and fish and wildlife management; construction began in 1973, and the dam entered operation in 1980. The state park was established in 1983 through a lease with the U.S. Army Corps of Engineers. Today it is a major public outdoor area for lake recreation, camping, fishing, boating, and wildlife watching.