Whitewater’s lakes are full of weeds.
To address this and make its lakes more usable, the city is looking at shutting them down for more than a year to clean out invasive species and deepen the shorelines.
Whitewater is exploring the idea of drawing down Cravath and Trippe lakes from fall 2019 until spring 2021, said Parks and Recreation Director Eric Boettcher.
Boettcher said the city is still in the information gathering phase. Ideally they could draw down the lakes, but it will eventually come down to how much it costs, he said.
When Boettcher started in his position in June 2017, one of the important issues put on his plate were the lakes, which have been filling up with sediment for years, he said.
If the city goes forward with a drawdown, it would open the dams and bring the water level down to a stream bead, according to a city handout.
The drawdown would, “freeze out and control invasive aquatic plants,” such as starry stonewort and Eurasian milfoil, the handout states.
A gradual drawdown would give fish and other wildlife time to locate to deeper water, too. Some fish, however, might not move downstream fast enough and would die.
Benefits to a drawdown include decreasing plant density and improving native diversity and lake depth, according to the city.
Some local businesses would see a negative economic impact, and the lakes would lose space for recreational activities.
Nearby, there was a drawdown on Little Muskego Lake in fall 2017. Boettcher said he spoke to residents around the lake who complained of a bad smell for about a week, but then the smell went away.
Whitewater is looking at doing a complete drawdown, Boettcher said, so the city could see where a navigable channel would be in the water. Dredging along that channel could lead to better recreation and a better environment for fish.
Dredging would be done during the winters to take advantage of the frozen ground, he said.
The city in February brought in a $25,000 planning grant and could apply for more grant money if the project moves forward.
Last month, Ayres Associates took soil samples for an analysis, and results could come at the end of the month.
“That ultimately determines what we can do with the dredging,” Boettcher said. “Then it becomes a question for the community, ‘Is it worth it or not?’”
Then comes a presentation for the city council. That should happen in September or October, according to his timeline.
The council would need to vote to approve the project, but right now Boettcher emphasized his department is still looking at its options.
If the city moves forward with Boettcher’s projected timeline, an average spring rainfall would bring lake water levels back to normal by June 2021.