EASTHAMPTON — Invasive water chestnuts and milfoil are making a reappearance in Nashawannuck Pond, prompting herbicide treatments and volunteers to step up and remove half a pickup truck’s worth of water chestnuts on Saturday morning.
Water chestnuts and milfoil have long been a nuisance in the pond, according to Paul Nowak, chairman of the Nashawannuck Pond Steering Committee, and the plants are once again taking hold this year.
The pond weeds “make the pond look not so great for the general public,” Nowak said, “and it impeded recreational activities such as fishing, kayaking and canoeing.”
Additionally, large volumes of the pond weeds can deplete oxygen from the water, he said, harming fish.
Invasive species can make their way into the pond in a variety of ways. Plant seeds will sometimes attach to boats and their trailers, or can be carried from water body to water body by ducks, geese and waterfowl.
“If too many weeds — especially invasive — fill the pond, they’ll take over and eventually turn it back into a swamp if they aren’t monitored,” said Beth Tiffany, a member of the steering committee.
“You can’t really stop the proliferation,” Nowak said. “You just try to keep up with it.”
In 2002, volunteers removed almost 10 tons of water chestnuts from the pond.
The situation isn’t as extreme this time, with water chestnut growth appearing to be in early stages, according to Nowak. When the plants are sighted, “you want to pick them right away,” he noted.
The water chestnuts must be removed by hand, with volunteers working from kayaks and canoes.
Last week, the city treated the pond with herbicides targeting the milfoil. The pond was also treated in 2016, 2017 and 2019.
In 2010, the pond was drained and dredged as part of a $2.3 million project, removing “years of sediment and weed growth,” according to the steering committee, and “allowing for a deeper, cooler channel designed to impede weed growth and encourage an improved natural habitat for fish and other species.”
While pond weeds continue to grow in the water, Nowak said, their prevalence would be worse if not for the dredging.
“When you make the pond deeper, it gives light less of a chance to reach the bottom,” Nowak said, “and plants need light to grow.”
Nashawannuck Pond originally covered around 50 acres when it was created in 1847, but lost around 20 acres of area to sediment runoff during its history. The 2010 dredging removed over 40,000 cubic yards of sediment, which primarily added to the pond’s depth.
The steering committee attracted ample volunteers when it put out a call for assistance with the water chesnuts this year on its Facebook page, Nowak said. Valley Paddler rentals also volunteered the use of its boats.
The pond “is the icon of our city,” Nowak said, “and borders Nonotuck Park, providing wonderful access for people and the water … We welcome all the assistance we can muster.”