Thief River Watershed Monitoring and Assessment Report

The Thief River Watershed (HUC-09020304), located in the Red River Basin, drains 624,422 acres in northwestern Minnesota. The watershed is almost entirely within Marshall and Beltrami counties (97.8%); the remaining 2% are within Pennington, Roseau, and Lake of the Woods counties. The Thief River starts at Thief Lake and flows 39 miles to its confluence with the Red Lake River in Thief River Falls. Agassiz National Wildlife Refuge (NWR) makes up much of the watershed's western boundary and continues to be a popular tourist destination for people seeking recreational activities. Aside from the refuge, land in the watershed is primarily used for agricultural purposes. Stream channelization is extensive, and because of the low gradient nature of the watershed, flooding and wind erosion is a major concern.