The Mississippi River - Winona watershed covers 419,200 acres in Wabasha, Winona, and Olmsted counties in southeast Minnesota. The Whitewater River falls within this watershed and is well known for its state park and trout fishing. A majority of the watershed is cropland, with forest and grassland covering large portions as well. Only a small percentage of the watershed is developed. The river discharges into the Mississippi River at Weaver Bottoms, an important Mississippi River backwater and waterfowl staging area. The largest city in the watershed is Winona (pop. 27,000), located on the Mississippi River.
The western portion of the watershed consists of gently rolling land that is heavily row cropped. The eastern portion of the watershed is more rolling, and is dissected by steep valleys with wooded slopes. The crop fields in the western portion are smaller, with more hay and pasture present. Dairy and beef are the major livestock types in the watershed.
The lower portion of the watershed supports a healthy population of brown trout, and flows through the Whitewater Wildlife Management Area. Picturesque limestone bluffs and deep ravines make Whitewater State Park a popular destination. Anglers find brown, brook and rainbow trout in the spring-fed Whitewater River and Trout Run Creek.
The watershed has a history of damaging floods, including one in 2007 that reshaped the river.
What's being done
Monitoring and assessment
The MPCA began monitoring of this watershed in 2010 by studying the biology at 38 stream locations and the sole lake in the watershed, Lake Winona (307 acres). The intensive monitoring and assessment report is posted below. The Stressor Identification report and TMDL reports are completed and posted below. Intensive water monitoring shows that the Mississippi River-Winona watershed has stretches impaired by sediment and other material that make the river too cloudy at times to support aquatic life. Bacteria and nitrate levels are also a concern in several streams.
- Mississippi River - Winona Watershed Monitoring and Assessment Report
- Mississippi River - Winona Watershed Biotic Stressor Identification Report
- Summary of Mississippi River - Winona Watershed Biotic Stressor Identification Report
Strategy development for restoration and protection
A 2009 project funded by the American Recovery and Reinvestment Act has established a farmer-led watershed council to address concerns on the agricultural side of the impairment issue. The council continues to meet with the purpose to “work proactively to protect and improve the waters of the Whitewater River Watershed through education, public awareness, innovation and the implementation of a wide variety of conservation practices that work for individual farmers and farm operations resulting in the removal of all Whitewater River segments from the EPA list of impaired waters under Section 303(d) of the Clean Water Act. The council believes that it is those that live in the watershed are best able to protect and improve water quality.”
A key partner in restoration and protection efforts is the Whitewater Watershed Project, which is leading several initiatives in the larger Mississippi River-Winona watershed.
- Mississippi River-Winona Watershed Final TMDL Study (wq-iw9-18e) (EPA approved 7/15/2016)
- Mississippi River-Winona WRAPS (wq-ws4-28a) (MPCA approval 11/1/2016)
- Mississippi River-Winona SWAT Modeling Project and LiDAR Analysis (wq-iw9-18n) (7/25/2014)
After a resident reported a fish kill on Garvin Brook in Winona County on Sept. 26, 2019, three state agencies responded by surveying the extent of the kill, taking water samples, walking the stream and tributaries, and talking with landowners. The investigation team met several times to discuss the lab analysis of water samples and other information.