Marsh Lake Ecosystem Restoration Project, Minnesota

U.S. Army Corps of Engineers, St. Paul District
Published Feb. 27, 2015
Updated: April 15, 2024


Modify the existing Marsh Lake Dam to increase the biodiversity of the Minnesota River/Lac qui Parle/Pomme de Terre River ecosystem without compromising the flood risk management function of the Marsh Lake Dam.


Marsh Lake is located on the Minnesota River between Swift and Lac qui Parle counties near Appleton, Minnesota. The Corps of Engineers owns and maintains Marsh Lake Dam as part of the Lac qui Parle Flood Risk Management project. The fixed-crest dam holds a conservation pool in the upper portion of the Lac qui Parle Reservoir.


Between 1936 and 1939, the Works Progress Administration constructed the dam and rerouted the Pomme de Terre River into the reservoir. The Corps modified the dam between 1941 and 1951 as part of the Lac qui Parle Flood Risk Management project. During floods, the Marsh Lake Dam is inundated by the Lac qui Parle pool and serves no significant flood risk management purpose.

Marsh Lake lies within the Lac qui Parle Wildlife Management Area, managed by the Minnesota Department of Natural Resources. In the fall, as many as 150,000 Canada geese use the management area at one time. Marsh Lake is also home to Minnesota’s largest breeding colony of American white pelicans and several species of fish. The project features include:

  • Restoring the Pomme de Terre River to its natural channel,
  • Modifying the dam with a fishway for fish passage,
  • Constructing a drawdown water control structure and
  • Constructing recreational features.

In combination, these features contribute toward restoring river habitat, eliminating winter oxygen refuge for carp and providing for ecosystem connectivity. The natural flooding and drying cycles will be restored, promoting growth of emergent vegetation, increasing waterfowl habitat and reducing sediment resuspension.


The project feasibility study was approved in 2012. The Corps executed the design agreement in fiscal year 2014. Construction completed in June 2020 and the ceremonial ribbon cutting took place in July 2022. The project is currently in the 10-year adaptive management and monitoring phase.


Congress authorized the study by a resolution of the Committee on Public Works of the U.S. House of Representatives on May 10, 1962, and authorized this project specifically in the Water Resources Reform and Development Act of 2014.


All costs are shared 65% federal and 35% non-federal. All federal funds have been appropriated. The Upper Minnesota River Watershed District’s share of the costs are funded by the state of Minnesota.

Planning, Engineering and Design Cost       $1,300,000

Construction Cost

Federal                                                 $7,600,000

Non-Federal                                         $4,500,000

Total Construction Cost                             $12,100,000

Estimated Total Project Cost      $13,400,000