Lake Ocheda management plan changes
WORTHINGTON -- In a meeting between the the Okabena-Ocheda Watershed District and the Minnesota Department of Natural Resources earlier this week, it was decided to alter the Lake Ocheda Management Plan before it goes before the DNR commissioner ...
WORTHINGTON - In a meeting between the the Okabena-Ocheda Watershed District and the Minnesota Department of Natural Resources earlier this week, it was decided to alter the Lake Ocheda Management Plan before it goes before the DNR commissioner this fall.
The watershed district hosted two public meetings on the plan earlier this year, during which several attendees asked for the temporary drawdown of the three-basin lake to begin a month earlier than the Sept. 1 date outlined in the plan.
The temporary drawdown will aid in a fish kill and encourage vegetative growth in the shallow prairie lake. The roughfish population has eliminated any plant growth in Lake Ocheda, which has led to poor water quality and clarity, as well as substantial algal blooms during the summer.
When the plan was written last year, it was done so with feedback from riparian landowners - several of whom voiced concern about cattail growth during a drawdown.
Okabena-Ocheda Watershed District Administrator Dan Livdahl said Friday that moving the drawdown up to Aug. 1 will likely not encourage cattail growth.
“Cattails need to have air and dry ground to germinate - they do that best in May-June,” Livdahl said.
The earlier drawdown would allow for the lake to drain at a slower pace and benefit more from evaporation.
“We think it will take a month to draw down the lake if there’s no water coming into the lake,” Livdahl said.
The earliest a drawdown could be conducted is in fall 2018, which is timed with the estimated completion of the Lewis & Clark Regional Water System to Worthington.
Livdahl said several factors will go into the decision on when a drawdown is conducted on Lake Ocheda. If it’s a wet year, the drawdown likely wouldn’t be effective. The same holds true if there is a large rain event following the start of a drawdown.
Lake Ocheda is fed by multiple water sources, from Lake Okabena in Worthington to field tile, numerous wetlands and groundwater during rain events.
“As we’re doing a drawdown, the amount of water coming in is really important,” Livdahl said. “We have to have relatively low flow coming in to make it successful.”
A team of local leaders will be assembled to monitor conditions prior to and during the lake’s drawdown, including both the watershed district’s board of managers and advisory council, along with DNR staff, Worthington Public Utilities, and Nobles County commissioners. Two representatives from the public will also be asked to join the team.
In pushing up the drawdown by one month, Livdahl said some people may be concerned about the loss of recreation on the lake during August.
“To be honest, water quality is poorest in August and there probably isn’t a lot of water-based recreation going on that time of year,” Livdahl said. “That’s the time when algae blooms are the worst. Fishing itself is not real good at that time of the year as well.”
Letters will be sent to riparian landowners on the change in drawdown date, and the public will have one more opportunity to comment on the management plan during a public information meeting at 7 p.m. Sept. 11.
The date for the hearing with DNR commissioner staff was set for 7 p.m. Oct. 10. A location has yet to be announced for both meetings.
Meanwhile, Ducks Unlimited will work on plans to modify the existing dam and fish barrier on the west basin of Lake Ocheda. The dam is owned by the DNR, but the Okabena-Ocheda Watershed District will be responsible for the cost of modifications. The current estimate for the work is $300,000, which Livdahl said will be paid for through tax revenues from residents within the watershed district.
Other than engineering the dam structure, Ducks Unlimited will not be involved in future management of the lake.