City will map depths of Lake MitchellCommittee says work could be done at reasonable cost.
By: Tom Lawrence, The Daily Republic
The depths of Lake Mitchell will soon be mapped.
The Lake Mitchell Advisory Committee decided to conduct a lake depth survey during its monthly meeting Tuesday afternoon at the Rec Center. No timeline was set, but the goal is to do it this year.
“There are several different benefits. It’s going to give you a baseline of your water volume,” said Parks, Recreation and Forestry Department Director Dusty Rodiek. “It’s going to give you a baseline to judge your future sedimentation.”
The lake doesn’t get a lot of that, he said, but as banks erode, sediment will fall into the water. By establishing a baseline, the city will be able to determine how quickly that happens, and what impact it has had.
In addition, while the city no longer relies on the lake for potable water, if it does return to using it in the future, it would be useful to know how much water is in it, he said.
Such a measurement also would be useful to anglers, Rodiek said.
He said as far as he knows, the city has never done this before, and there are no reliable maps of the man-made lake’s depth. The lake is believed to be 24 to 27 feet at its deepest.
“There’s depth maps out there for Lake Mitchell … and they’re garbage, for the most part,” Rodiek said.
He said the city engineering department, including Public Works Deputy Director Terry Johnson and Building Inspector John Hegg, said they could conduct the mapping. Renting the mapping equipment would be “relatively inexpensive,” Rodiek said, with a cost between $500 and $800.
Committee chairman Mark Puetz asked if the lake could be remeasured after water flows into it at an unexpected rate, such as when an upstream dam collapsed in 2010.
“You could pick and choose from major events if you wanted to redo,” Rodiek said. “It’d be good to do.”
Volunteer Day planned
People are being asked to help during the lake’s annual volunteer day on Saturday, May 4.
“Basically, we’re looking to do some re-vegetation and shoreline restoration,” Puetz said. “We want to take advantage of the lake being low, or lower.”
One of the primary goals is to pluck some cattail bulbs from a marshy area near the city dog park and transplant them to the lakeshore, where they would serve to stabilize the shoreline, provide fish habitat, and serve as biofiltration devices, Puetz said.
Dakota Wesleyan University students will harvest bulbs from the dog park area on Tuesday, April 30. Committee members were assigned to contact clubs in the community to get them involved in the effort, since it’s unclear how much work can be accomplished.
“It depends on the workforce,” Rodiek.
Puetz said the committee could request some city funds for bulb placement during the 2014 fiscal year process.
Puetz will make a presentation to the City Council Monday night. It’s a regular chore for the committee, since the council wants to be kept informed, said committee member Troy Helleloid.
Shoreline work at the Mitchell Prehistoric Indian Village has been completed, committee members were told. Some natural vegetation will be planted in the area to create more fish habitat.