WORTHINGTON — The planned drawdown for Lake Ocheda began Wednesday, despite the best efforts of beavers that built a large dam along the water’s route to Lake Bella.
“We’ll probably be dropping the (water) level a bit slower this year because of the beaver dam,” said Dan Livdahl, administrator of the Okabena-Ocheda Watershed District, who visited the official, human-built Lake Ocheda Dam to pull its stop logs Wednesday.
The beaver dam, which was discovered last spring on OOWD land, is about four feet tall, covered with vegetation and spans the entire width of the Ocheyedan River. Because the beaver dam creates wetlands water storage, holding back floodwater and reducing the amount of sediment running into the lake, the Minnesota Department of Natural Resources and the OOWD together opted to leave the unofficial construction as it is.
Lake Ocheda water from the drawdown was expected to either flow out of the river around the sides of the beaver dam or wash out the dam’s sides, Livdahl said.
The DNR ultimately decides whether to attempt a drawdown on Lake Ocheda, and the watershed district offers input and performs the drawdown. Livdahl will monitor the situation to ensure the water ends up in Lake Bella and not on nearby agricultural land.
The half-foot drawdown will be the second consecutive drawdown for Lake Ocheda, after a previous drawdown in 2020-2021 failed to fully achieve its goals. That winter just wasn’t cold enough to kill all the rough fish that stir up sediment and destroy vegetation in the lake, harming water quality. Because of this year’s drought, the nutrients left in the lake from the dead fish weren’t flushed from the lake either, Livdahl said.
This time, the hope is that Minnesota “experiences more typical winter weather” and the fish winterkill is more intense, a Watershed District press release noted.
The plan is to keep water levels low through April 2022.
In other news, the board:
Adopted a watershed district levy of $253,000 for 2022, as well as a proposed budget featuring $261,750 in total revenue and expenditures.
Heard about the district’s continuing discussions with District 518 regarding the potential creation of a large pond on its property southwest of the new intermediate school. If built, the pond would reduce the amount of runoff draining from agricultural land and flowing into Lake Okabena, improving the lake’s water quality. The watershed would apply for a Clean Water, Land and Legacy grant from the state in order to pay for the $1.25 million project.
Received an update on the toxic microcystin algae blooms sometimes present in Lake Okabena, often in August and September. The algae can kill pets if ingested, and it also causes rashes and allergic reactions in humans if touched. Livdahl warned lake-goers to avoid areas where the water resembles greenish paint, and to be aware that any time someone swims in a freshwater lake or stream there are potential algae toxins.
Livdahl’s 14 tests at Lake Okabena resulted in three positive results at Sailboard Beach on Aug. 2, 3 and 6, and one positive test result on Aug. 9 at the intersection of Seventh Avenue and Lake Street.
Granted three permits for pollution prevention and erosion control for a two-unit condo to be built at 2343 and 2347 Cherrywood Lane, construction and yard reshaping and seeding at 625 West Shore Drive, and a natural gas service line project in Worthington. Permits are required for construction projects.
Watershed managers and Livdahl expressed frustration with the current situation at construction sites, which were all out of compliance with their permits. Between the drought and the recent floods, it has been extremely difficult for anyone to get enough grass growing to control erosion.
Learned that the terms of watershed managers Steve Bousema and Jay Milbrandt will expire in October, and that both will re-apply for the positions.