SALISBURY — Starting this week a “very critical” lake aquatic plant survey is being conducted by Northeast Aquatic Research (NEAR), the results of which will guide the Twin Lakes Association’s (TLA) second herbicide attack in mid-July on non-native hydrilla, which was identified in East Twin last summer in the marina and northeast cove. The survey will also aid in the treatment of invasive milfoil, focused mainly in East Bay and along the south shore.
That news was among the updates presented at the Twin Lakes Association’s 90-minute membership meeting at Camp Isola Bella on Saturday, June 22, attended by a standing-room-only crowd of more than 100 attendees.
Among topics discussed was a lake management report including rising expenses and recent grants, updates on land conservation efforts and a watershed study being conducted in conjunction with Housatonic Valley Association (HVA), and the status of a recently instituted ramp monitoring program at O’Hara’s Landing Marina.
TLA board member Russ Conklin, who was appointed vice president of lake management, gave an update on measures taken this year to eliminate hydrilla and other aquatic weeds and an overview of future initiatives.
Conklin noted that when hydrilla was discovered last summer near the East Twin Lake marina, making it the first lake in the state to become infected with the worrisome weed, the association was on its own in dealing with the environmental threat. By the end of 2023, he said, the TLA assembled a formidable coalition of state, national and environmental experts and scientists, a handful of whom hold PhD’s, he said, noting, “it has helped us a lot.”
A team of scientists toured the lakes in early May to assess the hydrilla threat and discuss treatment strategies for this year. At that time, hydrilla was still dormant, but it was expected to begin to show itself by July, despite a herbicide treatment last fall.
Keith Hannon of the U.S. Army Corp of Engineers, which is part of the TLA coalition, is running six pilot tests of herbicides in the Connecticut River, which has been battling the non-native hydrilla for several years, the data of which will be available by the end of the year.
Hydrilla is not the only nuisance weed at the lakes, as milfoil, invasive Curly Leaf Pond Weed, and an early algae bloom in West Twin, are also on the TLA’s radar.
Conklin reported that the association worked with New England Aquatic Services to clear invasive Curly Leaf Pond Weed around the boat launch at Salisbury School, and that with continuous treatment or hand pulling, this invasive weed can be eliminated from Twin Lakes over the next three to five years.
Conklin also noted an unseasonable algae bloom in West Twin, which may be the result of nutrient-rich runoff, possibly from a faulty septic system. While the unsightly algae is not harmful, he reminded property owners to pump their tanks every year or two. Recent heavy rains, he said, could also account for the phosphorus input.
The focus this year in terms of lake management, Conklin said, is on hydrilla and milfoil, and specific treatment locations for milfoil and hydrilla will be informed by the aquatic plant study by limnologist George Knoecklein of NEAR, kicking off this week. The public and TLA community will be notified in advance.
Given the rare and endangered plants in the northeast cove, said officials, the TLA is committed to surrounding any beds of hydrilla with limno barriers to prevent the migration of plant fragments and to measuring concentrations of herbicide levels both within and outside the barriers.
One audience member asked if a permit was sought by the TLA before blocking off passage under the Isola Bella bridge with a barrier to keep hydrilla from spreading, and if not, questioned the association’s legal authority to prohibit public access.
In response, TLA President Grant Bogle noted that it was a “collective recommendation” by several coalition members, including the state Department of Environmental Protection (DEEP) and Connecticut Agricultural Experiment Station (CAES), among others, “that we close this passage off, and we did.” Thunderous applause followed.
Bogle continued: “This plant doubles in mass every two weeks. This is not an issue to take lightly. We anticipate we can get this under control in the next several years.”
Focus on the watershed
In other business, the TLA is proposing bylaw changes “designed to reflect our new reality as an organization with a vastly larger budget and greatly expanded responsibilities.” The membership voted unanimously to add “the watershed” to the existing language of areas the association protects and preserves.
Tim Abbott, Regional Conservation and Greenprint Director with the Housatonic Valley Association (HVA) noted that “what is happening in the watershed is affecting the quality of your lake and is equally important downstream.”
“HVA is delighted to be working with the TLA on a watershed study primarily focused on the draining into the lakes and Schenob Brook,” noted Abbott. The study is being funded by a $75,000 grant from the Bates Foundation to formally examine the watershed’s impact on Twin Lakes.
“There has been a tremendous amount of conservation within this watershed, and a lot of it in Massachusetts,” noted Abbott.
TLA member John Landon, co-chair of the Salisbury Association Land Trust, reported progress on conservation efforts involving several key parcels of undeveloped land within the watershed.
Bogle reported that a critical membership drive is underway as the TLA seeks to raise awareness of funds related to the battle to contain and eventually eradicate hydrilla, and that membership dues have been increased from $25 to $50 per member. The association is also looking to boost its membership through direct mail and outreach efforts, and beef up fundraising efforts.
TLA expenses, he said, have increased more than 10-fold to $250,000 a year since hydrilla’s arrival. The association applied for, and received this spring, a $75,000 grant, the maximum amount awarded, from DEEP through its Aquatic Invasive Special Grant Program. The funds are earmarked for control and management of hydrilla and Eurasian Water Milfoil.
Bogle said the aquatic plant surveys, which cost about $65,000, are “very critical” to lake management and will be repeated several times through October.
“We are out on the lake frequently doing post-treatment surveys to see if hydrilla has moved. And the herbicides, they’re expensive,” as are the needed control tools, like the limno barriers, divers, he explained. “Water quality testing costs us $2,500 every time a boat goes in. But it’s essential, and it’s the only measurements we have for what’s going on in the lake.”
The TLA is footing the cost of the new boat ramp monitoring program at the marina. Adam Mayer, who oversees the project, now in its 7th week, reported that more than 300 boats have been inspected, roughly two-thirds of which are from Connecticut. Only two boat owners, he said, refused the voluntary inspection. Áll boats going in have been clean so far,” said Mayer.
Bogle said heightened fundraising and monetary donations by the membership will go a long way toward keeping the TLA budget afloat while waging the hydrilla battle. “It’s going to be a game of cat and mouse for some time, and we can’t count on the DEEP grant every year.”
