Dane County Launches Expanded Fleet of Weed Cutters to Fight Lake Flooding

May 28, 2019
Ariana Vruwink (608) 267-8823
County Executive

Today, Dane County Executive Joe Parisi joined Department of Land and Water Resources staff at Olin Park to launch the county’s fleet of aquatic plant harvesters for the first time this year. The county is adding two new harvesters to its fleet. The 13 harvesters will aid county efforts to mitigate flooding in the Yahara Chain of Lakes. Dane County’s total operating budget for lake weed management in 2019 is $773,400—an over 53 percent increase in funds compared to last year.

“These aquatic plant harvesters will help advance our efforts to mitigate flooding due to climate change rains and more quickly move water through the Chain of Lakes system,” said Dane County Executive Joe Parisi. “We increased our number of aquatic plant harvesters and staff in the 2019 budget to enhance our preparedness if we face continuous, heavy rains again this season.”

Harvesting of aquatic plants occurs over an area of 485 acres of water and 64 miles of shoreline in the Yahara Lakes. Following last August’s heavy rains, a team of Dane County aquatic plant harvesters worked the river corridor and successfully doubled the flow of water moving south out of the Yahara Chain. Last year, 1,847 loads of aquatic plants were removed, resulting in around 8,496 tons of material leaving the Chain of Lakes system. About 691 loads (or 3,178 tons) were removed for flood mitigation.

In addition to flood mitigation, aquatic plant removal can also cut down on the amount of phosphorus found in the Yahara Chain of Lakes, which can increase the frequency and extent of hazardous algae blooms. Roughly 4,851 pounds of phosphorus was removed from the Chain of Lakes system in 2018. It’s estimated that about one pound of phosphorus can produce up to 500 pounds of algae.

Equipment for the program consists of 13 harvesters, four dump trucks, four elevators, and three barges. Dane County’s 2019 budget added two harvesters, one barge, and $50,000 for additional limited term employees. Three full time employees  will work to remove aquatic plants this year, along with 24 LTEs.