The state park consists of three units located some two miles west of Macon, Missouri on U.S. Highway 36.

Flooding along the Little Chariton River was an ongoing problem for the residents of Macon County and elsewhere in northeast Missouri since the area was first settled in the 1830s.

Extensive channelization of the main Chariton River by private entities, local governments, and the U.S. Army Corps of Engineers, while alleviating flooding issues in some areas, exacerbated them for others.

[5] Long Branch Lake is the reservoir created by the dam, with about 24 miles of shoreline and a flood-control capacity of 98,000 acre-feet.

[9] The large public acreage surrounding the lake provide opportunities for viewing white-tailed deer, wild turkey, and migratory waterfowl.