a clump of Eurasian milfoil pulled from the waters of Cobbesseecontee Lake

Can Conservationists Save Cobbosseecontee From an Aggressive Lake Weed?

As the upstream battle against Eurasian watermilfoil stretches into a sixth year, the long-term health of Cobbosseecontee — and of lakes, ponds, rivers, and streams around Maine — could hang in the balance.

By Jesse Ellison
Photos by Tara Rice
From our May 2024 issue

It was the middle of October and Cobbosseecontee Lake was perfectly still, a mirror reflecting a sky thick with billowing clouds. Em Russell was standing on the stern of a little motorboat, wearing three wetsuits, one layered atop another, his face creased from the press of his scuba mask. He scanned the water, searching for a tiny sprig of green he thought he had glimpsed, a fragment of invasive Eurasian watermilfoil. Having just spent four hours submerged in the cold water filling a five-gallon bucket with the stuff, weeding the lake bed like some hell-bent gardener, he worried that a loose bit had eluded him.

Friends of the Cobbossee Watershed diver Em Russell surfaces with a fistful of Eurasian watermilfoil for Jennifer Peasnall, the group’s manager of conservation programs.
Friends of the Cobbossee Watershed diver Em Russell surfaces with a fistful of Eurasian watermilfoil for Jennifer Peasnall, the group’s manager of conservation programs.

For a few minutes, Russell and his team floated in silence. Then, Alex Dyer, conservation director for the nonprofit Friends of the Cobbossee Watershed, gently reminded him it was time to move on. At this point in the year, not to mention this stage of the battle, getting every last bit of the milfoil would present an impossible task. It was time to settle for removing the biggest, bushiest growths that had crept toward the surface of the lake. The upcoming weekend would see a bass tournament (bass, too, is an invasive species in the lake), with 40 boats from all over New England coming to fish. And while the state required that participants’ boats go through checks for hitchhiking invasives before and after the event itself, some competitors had shown up early and already been out on the water to scope for promising spots. Looking out across the 5,500-acre lake, it was hard not to think of Sisyphus endlessly rolling his boulder up a hill in an act of eternal futility. “Yeah,” Dyer said with a sigh. “The concept of scale is kind of a struggle, even for me.”

Eurasian watermilfoil is deceptively delicate in appearance. Its branches look almost like feathers — wisps of jade green on a slender stalk that calls to mind bamboo. Native to parts of Europe, Asia, and Africa, it’s often used decoratively in fish tanks. It showed up in U.S. waters in the first half of the 20th century, introduced either by the aquarium business or after stowing away in ship ballast. Outside of the environment where it evolved in balance with other native species, it can wreak havoc. Even a mild current can pull a piece loose, and that little piece can drift a long way, sprouting its own tiny roots wherever it lands. Over time, a patch of the milfoil can grow so thick that it blocks out sunlight, choking off natural life cycles, killing native plants and the fish and other aquatic animals that depend on them, in turn affecting birds, beavers, muskrats . . . everything. 

It also impacts the humans who like to play on the water. In the Midwest, some lakes have grown so thick with this variety of milfoil that recreation has become virtually impossible. Mechanical harvesters — boats that act like lawnmowers — are sometimes employed to cut channels so that boaters can get to deeper water, where the milfoil doesn’t get enough light to take hold. The shortcoming of that method of removal is that it releases huge numbers of fragments, only exacerbating the problem in the long run. 

Herbicides can be effective, but nobody is eager to dump chemicals into the water unless it’s absolutely necessary, so they’re only considered as a last-ditch measure, applied around patches too big to be pulled by hand. In Connecticut, state officials permitted the release of milfoil-eating sterile grass carp in one lake where, after decades of reasonably successful milfoil management, the plant had suddenly proliferated. The carp, however, turned out not to be sterile after all and devoured not just the invasive milfoil but native vegetation too. Now, the challenge is getting rid of the carp.  

Not only does Eurasian watermilfoil spread easily within one body of water but also from one body of water to another. A single stem might snag on a boat’s propeller or stick in a bilge pump or get sucked into a Jet Ski. Then, it can spawn a new infestation wherever the craft launches next. The plant has hitched its way across the country that way, and officials in Maine were on the lookout for years. In 2003, it found its way into a small, private pond in Scarborough, and the state deemed the risk of spread exceedingly low. In 2008, it took hold in a lake near Belgrade but was successfully knocked out with pesticides. A decade then passed without incident until, in 2018, the milfoil showed up in Cobbosseecontee.

Kayakers like Jennifer Peasnall (left) provide close support to divers, like Em Russel (middle and right) as they weed the lake bed, since a motorized boat might disperse fragments of milfoil.

Of the state’s more than 6,000 lakes and ponds, Cobbosseecontee made for a likely suspect. A lake-vulnerability assessment by the Department of Environmental Protection, also in 2018, had given Cobbosseecontee a nearly perfect score, indicating it was maximally vulnerable to invasives. Just off I-95 near Augusta, the lake is easy to access, and it has some 900 residences on its shores, plus multiple summer camps, a campground, two marinas, and two public launches. Now, the lake is ground zero in the state’s battle against invasive aquatic plants. 

The same factors that made Cobbosseecontee vulnerable to invasive plants also make it a likely source of spread. If something shows up there, it’s probably going to show up elsewhere too. Friends of the Cobbossee Watershed, as the group’s name suggests, is focused not just on Cobbosseecontee but on a 217-square-mile area containing 27 other lakes, ponds, and streams. The nonprofit formed in 2001 to help promote the long-term health of the aquatic ecosystem, and one of its surveyors was first to raise the alarm about the milfoil in the lake. After that, the Department of Environmental Protection sent staffers to confirm that the plant was indeed Eurasian watermilfoil (which is easily confused for other species, including native milfoils that are beneficial for lakes and for biodiversity more broadly). The department decided to deploy an herbicide, because the infestation was already substantial. For a time, the state and the Friends group were more or less alone in fighting the milfoil.

“We watched passively as that happened,” recalls John Weaver, a long-time member of the Cobbosseecontee Yacht Club who, in 2020, joined its board. “At first, you hear there’s a plant, but you don’t know how much of a problem it can be,” Weaver says. “Once we learned just how much damage it can do — to natural resources, and the economic impact it can have — there was a bit of an awakening. This isn’t just another plant.”  

Clockwise from top left: Friends of the Cobbossee Watershed conservation director Alex Dyer helming the group’s skiff; Cheryl Soucy, chair of the lake association’s membership committee, looking through an aquascope (which cuts through glare on the surface); Cobbosseecontee Lake Association board member John Stanek out on the water.

Studies from states with more history of dealing with Eurasian watermilfoil have found that when the plant spins out of control, it can ding lakefront home values by up to 20 percent. Some Cobbosseecontee property owners up and sold, out of fear for what was coming. Others banded together as it became clear that addressing the issue required more financial resources and manpower than the Department of Environmental Protection could provide. Cobbosseecontee Yacht Club changed its name to Cobbosseecontee Lake Association, and it became a chief fundraiser for Friends of the Cobbossee Watershed, financing the fight against Eurasian watermilfoil.

Ryan Eldridge has been visiting Cobbosseecontee Lake his entire life. His grandparents used to run a store in the area, and multiple members of his family have owned camps on the lake, including, currently, he and his brother. Eldridge remembers being aware of the yacht club as a kid and thinking to himself, “We don’t have the money for some yacht club.” These days, he’s well-known as a core cast member on cable television’s long-running Maine Cabin Masters, and he has made himself into something of a self-appointed ambassador for the yacht club turned lake association. “Cobbosseecontee has always been one of my favorite places in the world, especially as doing Cabin Masters has gotten crazier and crazier,” he says. “It’s like my therapy. I go out and float on the water, and everything makes sense.” 

Amid the anxiety over milfoil, Eldridge has found a silver lining. “What started as a subject that had a lot of tension has brought the community together,” he says. Other people involved with removal efforts echo the sentiment, stressing that even though Cobbosseecontee was particularly vulnerable to the milfoil, it’s also particularly well-positioned to tackle the problem. The lake’s local popularity has helped fundraising efforts (the lake association’s membership has more than doubled from about 300 to 700 people), and many concerned homeowners have been willing to take on essentially full-time, unpaid jobs for the lake association, doing organizing, fundraising, outreach, research, and more. “This couldn’t have happened to a better lake,” Eldridge says.

Early on, the lake association launched a capital campaign, in hopes of raising $1 million. Weaver, who’s now the group’s president, put together a presentation that tried to strike a balance between appealing to people’s love of the lake and reminding them of the dire threat to their property values. In PowerPoint slides, he paired that information with a photo of a chocolate Lab, sitting on a dock, looking plaintively at the camera. The campaign exceeded its goal, bringing in about $1.5 million. Much of the money raised by the lake association gets funneled to Friends of the Cobbossee Watershed, which then uses it to keep up surveying, milfoil removal, and inspections of boats being trailered into the lake (those inspections are optional for boat owners, but few ever object). 

By 2022, there were just three locations where milfoil was known to have a hold in Cobbosseecontee: two larger patches at the lake’s northern end and a smaller clump of plants in the middle of the lake, near the Kennebec Land Trust’s Horseshoe Island Preserve. The state had treated the larger patches with herbicide and the Friends focused on weeding the smaller patch. As the year came to a close, there wasn’t, as far as anyone could tell, any Eurasian watermilfoil still in the lake. 

Then, last summer brought an unprecedented level of rainfall, and the resulting runoff made the water murky. Many days were so rainy that survey teams didn’t go out on the lake at all. By the end of the season, Eurasian watermilfoil could be found in at least 15 different locations on the lake. “I felt like there was a false sense of victory in the community,” Eldridge says. “We got a gut punch, which I think is a good thing, because we needed it. This milfoil isn’t going away. Even though we raised a bunch of money, we’ve got to do more.”

One new spot where Eurasian watermilfoil took hold was the dam at the lake’s outlet, which posed a worst-case scenario. Because of all the rain, many dams in the watershed had been left open. Although the Department of Environmental Protection promptly hit the area by the outlet dam with herbicide, the milfoil still managed to get into Cobbosseecontee Stream, which flows into several ponds and, eventually, the Kennebec River. “That’s the thing that scares us,” says John Stanek, a board member at the lake association who owns a home on Horseshoe Island. “It has become a state problem. It has left our lake. The last thing we wanted to be is the exporter of this milfoil, but it’s now an all-hands-on-deck situation.”

State officials have resigned themselves to this reality too. “Initially, our goal was eradication,” says John McPhedran, a Department of Environmental Protection biologist who focuses on invasive aquatic species. “We thought it was relatively confined, and that was our aim. Now, seeing where it has spread, it’s probably very unlikely that eradication is possible.”

That isn’t to say Cobbosseecontee is a lost cause, especially not to the people who care most about the lake. The Cobbosseecontee Lake Association’s 2024 strategic plan increases annual spending on removal work from $162,000 to $290,000. Still, money only gets you so far, Eldridge says. “Milfoil isn’t going anywhere, and we have to educate, but nobody wants to be educated on vacation.” Now, signs at every launch remind everyone to clean, drain, and dry boats before moving from one body of water to another, and parts of the lake with ongoing infestations are marked off with buoys. Last fall, though, out on the little skiff that Friends of the Cobbossee Watershed uses, we watched as a speedboat flew past some of those buoys, kicking up exactly the type of wake that could help milfoil spread.

By then, it was crunch time. In the second half of October, the days were getting shorter and colder. Soon, the water level would be drawn down, docks would be pulled out, and the team would have to wrap up its work for the year, ahead of the eventual freeze. In the past, during colder winters, the Friends wouldn’t fall behind in their fight against the milfoil during the off-season, because the plant would go dormant. But with warmer winters, the milfoil seems to remain active year-round — just one more complication in a complicated effort.

In addition to fighting milfoil, the Cobbosseecontee Lake Association maintains Ladies Delight Light, reputedly the state’s only active inland-waters lighthouse. 

“For my job, I think all the launches should be closed and policed. It would make my work a lot easier, ” Dyer, the Friends’ conservation director, told me as she eyed a fishing boat with two massive hydraulic-pole anchors descending to the lake floor. “But from a Mainer point of view, I don’t want that. I think it would really affect our tourism. I think it would really kind of skeeve people out. You go to our Maine lakes to relax. Yes, from a professional level, shut them all down. But personally, no, I don’t want that.”

Two big yellow signs on the Friends’ skiff caution boaters, “slow, plant survey in progress.” Occasionally, people on passing boats will shout out to the Friends staff, thanking them for their efforts. Dyer knows the bigger picture of what the work means for the future of the lake and for the people who spend time on it, but she likes to keep her focus on the immediate task at hand. “It’s important to stay dispassionate,” she says. “It’s how you avoid burning out. Yes, it’s scary. But if every boater just followed ‘clean, drain, dry,’ we would solve so much.”

May 2024, Down East Magazine

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