The Bois de Sioux River ( ) drains Lake Traverse, the southernmost body of water in the Hudson Bay watershed of North America. It is a tributary of the Red River of the North and defines part of the western border of the U.S. state of Minnesota, and the eastern borders of North Dakota and South Dakota. It is about in length.U.S. Geological Survey. National Hydrography Dataset high-resolution flowline data The National Map , accessed 8 June 2011
Bois de Sioux is a name derived from French meaning "Woods of the Sioux".
Course The river flows northward from a Corps of Engineers dam at the north end of Lake Traverse and shortly enters Mud Lake. Downstream of Mud Lake it is a small stream, and its flow has been channelized and straightened in some places so that the watercourse diverges slightly from the historical state boundary. It passes the town of White Rock, South Dakota, before joining the Otter Tail River to form the Red River of the North at Wahpeton, North Dakota, and Breckenridge, Minnesota.
Tributaries The two largest tributaries of the Bois de Sioux are the Mustinka River, which flows into Lake Traverse, and the Rabbit River south of Breckenridge; both of these enter from Minnesota.
See also List of rivers of Minnesota List of rivers of North Dakota List of rivers of South Dakota List of river borders of U.S. states
References
Waters, Thomas F. (1977). The Streams and Rivers of Minnesota. Minneapolis: University of Minnesota Press. .