Cottonwood River

Cottonwood River near New Ulm

Watershed at a Glance

The Cottonwood River is located in southwestern Minnesota in the counties of Brown, Cottonwood, Lyon, Murray, and Redwood. It begins near Balaton in southwest Lyon County and flows about 150 miles east to the Minnesota River near New Ulm. The watershed area is approximately 840,000 acres or 1,313 square miles.

Hydrologic Unit Code:07020008
Intensive monitoring start year:2016
Major lakesMajor rivers and streams
No lakes in this watershed.
Cottonwood, Dutch Charlie Creek, Pell Creek


The entire Cottonwood River watershed has about 88% (739,000 acres) of the land in cultivation, 6% of the land in grassland, 1% is wetlands or water, and just under 3% is still wooded. The remainder of the land is farmsteads, gravel pits, rural development, and other land uses.

The topography is that of a rolling upland area. Altitudes descend from west to east with the Coteau des Prairies serving as a watershed divide. Natural drainage patterns in the area were established by valleys formed from glacial meltwaters. End moraines, which were formed during the recession of the last glacier, are the most prominent features. There are 15 incorporated communities in this watershed, including Tracy, Sleepy Eye, Springfield, and New Ulm, and there are 7 unincorporated communities.

    What's being done

    The Cottonwood River Watershed Project (CRWP) was awarded a Clean Water Partnership (CWP) Phase I Diagnostic Study grant by the MPCA in 1997 to begin an intensive study of land use and water quality in the Cottonwood River watershed. The CRWP was awarded a Phase II Implementation grant from the MPCA in 2000 to carry out the remediation strategies determined in the Phase I CWP.

    Subsequent grants were carried out to continue the implementation of best management practices (BMPs) outlined in the CRWP implementation plan as well as continued monitoring of surface waters in the watershed. Total Maximum Daily Load projects include a fecal coliform TMDL assessment in 2006-2009, and a turbidity TMDL assessment in 2008-2011.

    What is a watershed?

    Illustration showing contour of land directing flow of water

    Learn the basics of a watershed.

    Redwood-Cottonwood Rivers Control Area

    507-637-2142, ext. 4