Rapids Lake Education and Visitor Center 2008 Federal Duck Stamp Contest Phone: 952-854-5900 |
The Minnesota River, while a beautiful natural resource and the reason Minnesota Valley has such an extensive network of bottomland marshes, is now responsible for the degradation of these same wetlands. The large volume of water that enters the river from the altered watershed cannot be contained by the riverbanks and flow of water into Refuge wetlands is the result. Periodic flooding has always occurred in these systems and in fact is necessary. However, flooding now takes place at a rate which valuable wetland plants are unable to adapt to. The result is a degraded marsh that is little more than a sterile, silt-laden basin with little value to wildlife.
In order to keep Refuge wetlands in as productive a state as possible for wildlife, particularly migratory waterfowl, dikes and water control structures are used. By controlling water depths at different times of the year it is possible to manipulate the vegetation for the benefit of different wildlife species. Staff manage approximately 1,500 acres of wetlands throughout the Refuge with control structures. Rice, Fisher and Rapids Lake are among some of the wetlands that are managed in this way. A typical annual plan might call for a spring "drawdown" of water to solidify the marsh basin and allow plants to germinate and take root. Gradual reflooding in the fall provides waterfowl access to valuable food plants. Other plans may favor shorebirds or wading birds depending on how the water is manipulated.
With time, the Minnesota River may again be a positive influence on Refuge wetlands, but until such time, water control will be necessary to maintain quality habitat.
