Tenney Park Dam, where Lake Mendota drains into the Yahara River and flows toward Lake Menona. It’s a critical point in managing flood water drainage.Image By: Sydney Widell
County learns from past floods to prepare for the future
County officials will prioritize removing sediments from critical points in the Yahara Lakes and River this summer, in an effort to move more water through the chain of lakes faster and reduce the impact of future flooding.
The multi-year dredging project will happen in several stages at six locations and cost roughly $2 million, according to Analiese Eicher, a Dane County Board of Supervisors vice chair. The first round of dredging will take place between Lake Monona and Lake Waubesa.
“One of the things that was identified is that we need to be able to move water quickly through our chain of lakes and by removing the sediment strategically, we are actually able to increase the flow from one lake to another.” Eicher said. “It was something we could do well, and have the resources to do right away.”
As the Yahara Watershed confronts another flood season, it is still reeling from the impacts of last year’s, which wrecked more that $154 million in damages county-wide. Now, the County Board is looking to last year’s floods to prepare for the future.
In addition to dredging, the board has also prioritized pumping, aquatic plant harvesting, lake level evaluation, improved dam management and run-off retention as flood management solutions, based on recommendations from a Lakes Level Task Force that met throughout the spring.
“Based on the recommendations, we are starting to take some action,” Eicher said. “We don’t want what happened last year to happen this year.”
The task force formed in response to a technical report commissioned by Dane County to assess future flood risks and outline adaptation and mitigation strategies, following last summer’s floods. The working group behind the report was composed of city and UW-Madison engineers and water resources managers.