ABOVE: Curly-leaf Pondweed is visible near the shoreline of Hall Lake in Fairmont. The Minnesota Department of Natural Resources has confirmed the aquatic invasive species present in all five of Fairmont’s lakes.

FAIRMONT– Those who have spent time on or near Fairmont’s lakes have likely noticed the weeds overtaking the shoreline on each of the five lakes. The weeds are actually an aquatic invasive species called Curly-leaf Pondweed.

Hannah Neusch, a water resource technician with the city of Fairmont, said that while there’s many types of pondweed, curly-leaf is the invasive type. It’s a rooted, submersed aquatic plant that can grow to be 15 ft. tall.

“It’s not supposed to be here but it’s basically out-competed all of our native species that might have already been here,” Neusch said.

The weed was brought here, likely by a boat, a long time ago. Neusch said the Minnesota Department of Natural Resources (DNR) first had record of it being in Fairmont in 1993, though she suspects it may have been here before that.

The reason for the weed being so noticeable this year has everything to do with recent weather conditions. Neusch pointed out that the past couple years have been droughty, leaving the water more concentrated and murky.

However this year, runoff from excess snow melt, along with more spring rains, diluted the water, making them very clear. Curly-leaf Pondweed roots into the bottom of the lakebed and in order for it to start growing, the sunlight needs to touch it. If the waters are too murky, the plant can’t grow.

“We basically traded one issue for another, which is unfortunate but it is our current situation,” Neusch said.

Getting rid of the invasive weed can prove to be difficult.

“This plant will continue to grow back every single year until every single root is removed,” Neusch said.

However, there are a few options that lake property owners can consider if they’d like to remove the weeds.

The DNR’s aquatic invasive species specialist for Southern Minnesota, Carli Wagner, told Neusch that there are two ways to treat Curly-leaf Pondweed.

Typically, a permit is required per the DNR to treat it, however, if you’re a homeowner or business owner on the lakeshore and you want to remove Curly-leaf Pondweed in public waters that abuts your property, you can do it mechanically (by hand or rake) without a permit, as long as the area is no greater than 2,500 sq. ft. Anything beyond that, a permit will be required.

However, Neusch said, “If you do it mechanically, bits of the plant will break off and they could potentially re-root.”

The other option is treating the weed with herbicide, which would require a permit through the DNR.

“We in Fairmont drink our surface water, so that’s a touchy subject. The DNR would be the deciding factor on whether or not you’d be allowed to do that,” Neusch said.

For those who decide to mechanically remove Curly-leaf Pondweed, there’s a specific way to dispose of it, as it’s considered a prohibited invasive species, which means it’s unlawful to possess, import, transport or introduce it, except under a permit.

“If you rake it up, you should pile it on your property and let it dry out. Once it’s 100 percent dead, you can dispose of it however you would normally dispose of trash,” Neusch said

Curly-leaf Pondweed poses no threat to the public, it’s just a pesky weed that people don’t like to look at or swim through. Boat owners should also be aware of the weeds and be mindful to trim their motors when close to it.

“It’s annoying. It gets really thick,” Neusch said.

There is a bright spot when it comes to the current state of the weeds in Fairmont’s lakes. Neusch said it’s one of the first plants to start growing in the spring, which is why it got so thick so quickly.

“It’s seeding out right now. The little balls at the top of the plant are getting ready to fall off. In about two weeks, they’re all going to die,” Neusch said.

While the weeds will soon be gone, as they decompose, they’ll add nutrients back into the water which could contribute to an additional algae bloom which Neusch said might come mid-July.

However, until then, Neusch said people should continue to manage the Curly-leaf Pondweed until another way is figured out how to be more effective at managing it.

She pointed out that the city doesn’t own the water and homeowners don’t own the water. It would be the DNR and the DNR has tried to eradicate it in certain lakes in Minnesota and it wasn’t possible; the weeds came back.

“Now it’s just management for a couple months, wait for it to die off, dispose of it and get on with the rest of the summer,” Neusch said.

Even people who don’t live on the lake or have a lakeshore property can help. Neusch said everyone needs to work together to help manage the problem. Community members can help by controlling the amount of nutrients (phosphorus and nitrogen) that are allowed into the lake. These come from lawn fertilizer, fertilizer runoff from nearby farm fields and grass clippings and leaves being blown into the street and washed down the drain.

“All these things and more contribute to our nutrient load in our lakes and controlling them can limit the amount and severity of blooms we see on a yearly basis,” Neusch said.