Thief River Watershed Restoration and Protection Strategy Report

The Thief River Watershed (U.S. Geological Survey (USGS) Hydrologic Unit Code (HUC) 09020304) is in northwest Minnesota and is a tributary of the Red Lake River (USGS HUC 09020303) in the Red River of the North Basin (USGS HUC 090203). Most of the watershed area lies within Marshall, Pennington, and Beltrami Counties. The Thief River itself runs along the western side of the watershed and is joined along the way by tributaries that include the Moose River (Judicial Ditch 21), Mud River (Judicial Ditch 11), Branch 200 of Judicial Ditch 11, Marshall County Ditch 20, and Judicial Ditch 30. There are more than 30 impoundments and reservoirs in the watershed, including the Moose River Impoundment, Lost River Pool, Farmes Pool, the pools of Agassiz National Wildlife Refuge (NWR), and the Thief River Falls Reservoir. Agassiz NWR lies in the center of the watershed. Agassiz Pool, the main pool of the refuge, receives water from the Mud River from the east, Thief River from the north, and some smaller ditches. It discharges to the Thief River to the south.