Root River Watershed

Nestled in the southeast corner of Minnesota, the Root River and its tributaries are well-known to anglers for their exceptional trout fishery, including some native brook trout. The river and surrounding landscape are also popular with other outdoor enthusiasts for their beauty and the myriad recreation opportunities they provide.

The 81-mile-long river and its tributary streams drain more than one million acres in five counties before emptying into the Mississippi River. The region is not only important for tourism but for agriculture, yielding abundant corn, soybeans, beef, pork and other products. The diversity of stream habitats also makes the watershed exceptionally rich in mussels, insects and other aquatic life.

But water quality is poor in portions of the Root River. Changes in urban and rural land use have altered surface and stream flows causing stream banks to erode and introducing excessive amounts of sediment and nutrients into the Root and its tributaries, damaging water quality and aquatic habitat.

Working with growers and many county, state and other partners, The Nature Conservancy has developed a conservation plan to restore and protect water quality in the Root while ensuring that agriculture remains economically viable.

Research Assesses Effectiveness of Conservation Practices

The Conservancy and its partners are taking a two-pronged approach to conservation in the watershed that emphasizes science and innovation.

With funding from Minnesota’s newly-created Clean Water Fund and The Monsanto Company, a long-term study of the effects of existing and alternative agricultural management practices on water and soil quality in three Root River sub-watersheds has been launched. Partners include the Minnesota Department of Agriculture and local soil and water conservation districts.

Baseline soil and water quality data are being gathered, along with information about current management practices. Soil and Water Conservation District staff are working with farm owners to identify alternative management practices, including different types of tillage, crop rotations and manure handling that will reduce sediment and nutrient loss, while maintaining the farms’ profitability. As changes are made, the partners will continue to monitor soil and water quality to assess the results and refine management practices.

Innovation Could Help Solve Excess Nutrient Issues

Two examples of innovation in the watershed involve projects designed to minimize the negative impacts of agricultural drainage systems.

Working with two farm families and several state and county agencies, the Conservancy installed infiltration ponds and bioreactors on farmland along two tributary streams to the Root. Runoff from nearby farm fields is directed into the ponds where pollutants are filtered out by native vegetation before the water is slowly released through the bioreactors, which are buried trenches loaded with woodchips. Bacteria on the woodchips remove nitrates from the runoff before it is released into a ditch leading to the South Branch of the Root River.

The Conservancy and its partners are also testing a new type of ditch, called the two-stage ditch, to achieve the drainage farmers need while reducing nutrient levels and erosion. Vegetated “benches” are added to each side of the ditch, mimicking the floodplains that occur naturally along streams. The benches make the sides of the ditch more stable, thereby reducing ditch cleanout costs for farmers, and the vegetation helps absorb water during high flow periods and filter out nutrients.

To assess the impact of the new ditch and bioreactor system, the Conservancy is working with partners to monitor nutrient and water flow levels and the structures themselves to see how often maintenance is required. The partners will present their methods and results in technical papers that the Natural Resources Conservation Service and other conservation agencies can share with its staff and interested agricultural landowners in the region.

“To improve water quality and aquatic habitat in the Root and downstream in the Mississippi and the Gulf of Mexico at a scale that can really make a difference, we are working to find innovative, science-based solutions that keep rivers healthy for trout and other wildlife, while helping farmers improve both their environmental performance and their bottom line,” said Rich Biske, the Conservancy’s Southeast Minnesota Conservation Coordinator.

Project Funding: Cargill, Inc., General Mills, Inc., Kellogg Foundation, The McKnight Foundation, The Monsanto Company and others.

Project Partners: Board of Water and Soil Resources, Fillmore Soil and Water Conservation District, Minnesota Department of Agriculture, Minnesota Department of Natural Resources, Minnesota Pollution Control Agency, Mower Soil and Water Conservation District, Root River Soil and Water Conservation District, University of Minnesota, U.S. Fish & Wildlife Service, USDA Natural Resources Conservation Service, Winona Soil and Water Conservation District and Winona State University.