Posted on July 31, 2024
MITCHELL – In the fall of 2025, Lake Mitchell’s water levels will begin dropping to make way for the future dredging project.
When the lake drawdown is complete, Public Works Director Joe Schroeder said it will position the city to receive more favorable bids for the dredging project. The estimated cost of the mechanical dredging project is $25 million, but the exact cost won’t be determined until bids are received and approved.
The updated timeline of the lake drawdown and dredging project was provided to the Mitchell City Council on Monday during a work session.
“The plan is to draw down the lake in 2025 by using pumps. They will cut a hole in the sidewall of the spillway dam allowing water to flow through like a creek while the dredging project is going on,” Schroeder said of the drawdown process.
The city has $3.5 million allocated for the drawdown structure that will allow the lake’s water level to be drastically lowered. A large portion of the lake bottom will be exposed when finished.
As for the dredging project, work is slated to begin in 2026. The scope of the work will entail crews using heavy equipment to remove the phosphorus-rich sediment along the lake bottom. Schroeder said the dredging project is estimated to extend into 2027 and possibly early 2028.
“When the dredging is complete, that’s when the final drawdown structure will be installed,” Schroeder said.
The final drawdown structure will allow the city to perform maintenance on the wetland along Firesteel Creek and complete shoreline restoration work.
In June, Mitchell voters narrowly approved a $16.8 million loan application that the city was aiming to use as its primary financing tool for the lake dredging project. The approval of the state loan advanced the dredging project.
The spillway in Lake Mitchell.
Leading up to the June special election on the lake loan application, there were estimated timelines indicating the drawdown process could begin as early as this fall.
Council member Susan Tjarks was pleased to receive an updated timeline of the dredging project after receiving many questions from residents about the project schedule.
“I’ve had so many people reach out to me and say, ‘So, when are they going to start the drawdown? And are we going to have an empty lake this fall?’ I think there were a lot of assumptions in the public and lack of clarity,” Tjarks said.
As the project moves forward, Tjarks called on city officials to provide more updates to the public.
The sediment that crews remove from the lake bottom will be hauled to a spoil site located at Firesteel Park.
Firesteel Park sits on the west side of Lake Mitchell, where engineers have identified as an area with the most concentration of phosphorus-rich sediment.
With the spoil site being located next to the lake, city officials said it will reduce costs of the project due to shorter traveling distance for fuel-based heavy equipment.
The updated timeline of the project means residents will have another spring and summer to swim and fish in Lake Mitchell in 2025.
Engineers have confirmed that a significant fish kill will result from the dredging project. The state’s Game, Fish and Parks have agreed to restock Lake Mitchell with fish populations.
Mayor Jordan Hanson asked whether the city could request the GF&P to authorize liberalized fishing authorization in 2025 prior to the lake drawdown. Liberalized fishing allows anglers to catch an unlimited amount of fish for a short period of time.
“I think that could be a big draw, and people could eat a lot of food. It could be a lot of fun,” Hanson said.
