Corps officials held a public meeting to discuss the Sustainable Rivers Program July 15.
The Corps of Engineers, St. Paul District, is launching a new initiative to seek out Tribal, agency, and public partner’s ideas to improve the aquatic habitat at Mud Lake, in Traverse County, MN and Roberts County, SD. Specifically, we are looking at potential options and effects of increasing habitat for shorebirds and plants by changing lake water levels.
The Corps is also interested in input on general operations Lake Traverse and Mud Lake and associated consequences to the lakes and downstream. Input provided will help inform the early stages of a new water management plan for Lake Traverse and Mud Lake. Any new water management plan would involve a detailed review and public comment period separate from this comment period.
Mud Lake Drawdown
Under the Sustainable Rivers Program, the Corps is looking at opportunities and constraints of a potential annual drawdown of Mud Lake to provide better habitat for birds and aquatic vegetation.
Currently: Mud Lake is very shallow with little vegetation, limited habitat, and poor water quality.
Potential Opportunities: Annual drawdowns to simulate seasonal water level changes of a wetland to provide shorebird habitat. If drawdowns were to occur, Mud Lake would be gradually dewatered following the spring snowmelt via the White Rock Dam. The lake would then be slowly drained during summer to encourage seed‐producing wetland plants before a gradual increase in water toward the end of summer or early fall.
Known benefits of lake level drawdowns:
- Provides food for dabbling ducks and shorebirds;
- Brood habitat for pheasants and food for other birds; and
- Bird sanctuary viewing and hunting opportunities.
Constraints: Any potential operating changes to Mud Lake would need to be consistent with current flood risk management and water supply purposes of the Lake Traverse Project. The Corps is also aware and gathering more information on potential water quality and quantity concerns for the Bois de Sioux River.
Background: Lake Traverse & Mud Lake
Reservation Dam was built at the outlet of Lake Traverse and White Rock Dam was built just downstream on Mud Lake. Along with Brown’s Valley Dike, the dams make up the Lake Traverse Project located at the headwaters of the Bios de Sioux River which is a headwater tributary to the Red River of the North. During high water events, the two reservoirs merge into one. When this happens, the reservoir water levels are managed by the White Rock Dam.
Currently, the Lake Traverse Water Control Manual calls for maintaining water levels to provide water supply and flood storage during the spring. In general, water quality is poor in both Mud Lake and Lake Traverse.
The Corps is soliciting input on changes to the current water control operations for Lake Traverse and Mud Lake. The current operations:
Spring Drawdown: Lake Traverse is lowered in March depending on snowpack conditions.
Spring Runoff Operation: Generally, the amount of water that is released from the White Rock Dam is the same as the volume of water that enters Lake Traverse from the Mustinka River.
Exceptions to this occur during floods. When river flow exceeds channel capacity, 1,100 cubic feet per second, (imagine the volume of 1,100 basketballs passing every second) the following operations occur. First, the Corps looks at the Red River level in Wahpeton, ND. If the river in Wahpeton is high, the White Rock Dam is closed. Then, river flow is released again once the Red River in Wahpeton drops OR lake levels at Traverse reach the Top of Flood Control. When the Top of Flood Control is Reached MN Highway 117/SD Highway 19 that overlies Reservation Dam is overtopped. Lake Traverse and Mud Lake merge and become one lake during large flood events.
Summer/Fall Operation: Generally, the amount of water that is released from the White Rock Dam is the same as the flow of water that enters Lake Traverse from the Mustinka River.
Except for flood events when the river exceeds channel capacity (see flood events during spring).