It is located in west central Minnesota within Lac qui Parle, Lincoln, Yellow Medicine counties, and northeastern South Dakota. There are 6 municipalities in the watershed of which the city of Madison is the largest. The Lac qui Parle River major watershed area is approximately 1,097 square miles or 702,119 acres. The watershed is subdivided into 78 minor watersheds. The minor watersheds range in size from 2,844 acres to 32,090 acres with the mean size approximately 9,002 acres.
Agriculture is the predominant land use within the watershed.
The Lac qui Parle River and its tributaries, public and private drainage systems, lakes and wetlands, define the drainage network of the major watershed. The Lac qui Parle River flows to its confluence with the Minnesota River above the Lac qui Parle Dam in Lac qui Parle County. The total distance of the stream network within Minnesota is 1,434 miles of which 1,052 miles are intermittent streams and 382 miles are perennial streams.