Meeting Minutes Oct. 8, 2025

Attendees:  Josh Burnside, SePro, Jon Gosselin, SePro, Jennifer Torres, NEAR, George Knoecklein, PhD, NEAR, Dominic Meringolo, SOLITUDE Lake Management, Greg Bugbee, CAES, Riley Doherty, CAES, Keith Hannon, USACE, Ellie Clark, CT DEEP, Matt Glokowski, CT DEEP, Carlie Richie, CT DEEP, Bill Moorhead, CT DEEP, Vincent Long, CT DEEP, Kara Sliwoski, MA Dept of Conservation and Recreation, Debra Aleksinas, the Lakeville Journal, Barbara Heinemann, Mt. Riga Corporation, Jim Morril, LWA, Christina Astrove, Doolittle, Andrew Cahil, Mudge Pond, Stacey Dodge, Town of Salisbury, Maria Horn, State Representative, Kitty Kiefer, Salisbury Selectperson, and the following TLA members:  Grant Bogle, Bill Barton, Russ Conklin, Rich Haupt, Carey Fiertz, Jean Bell, Dave Haab, Jodi Haupt

The meeting started at 11:05 pm and everyone was welcomed by Grant Bogle.  The first order of business was to do a round of introductions and to ensure that everyone had registered their attendance on the sign-in sheet. 

Grant turned the meeting over to Russ who showed the group a map of the Twin Lakes watershed, noting the unique geological formation of Twin Lakes, the fact that we harbor many state listed species and nearly 60 native species of plants, and that we flow into some of the most unique and diverse habits in the NE including Shenob Brook.  Russ then reviewed a chronology of lake management activities for the 2025 season, beginning in March with the first water quality testing and ending in the late fall.  This included a brief discussion of the treatment of curly leafed pond weed in Middle and West Twin in late May and then hydrilla in the NE cove of East Twin throughout the summer.

Dominic then took the group through a detailed review of the hydrilla treatment strategy which included serial treatments in the NE cove of East Twin.  Sample charts were reviewed showing the treatment tracks of the herbicide application boat along with the amount of herbicide put into each of the sections of the NE Cove for one treatment simply as a demonstration of the level of data collected and the precision of each application.  Finally, Dominic showed the test results which confirm that SOLITUDE was able to maintain an average of 2-5 ppb of SONAR within the treatment area over the course of the season, consistent with the TLA herbicide permit.

George then stepped up and discussed the history of treating hydrilla on Twin Lakes, beginning with its discovery in June 2023.  He discussed the use of ProcellaCOR in the marina in early September 2023, which had minimal effect, followed by numerous treatments using various herbicides in 2024 that failed to stop hydrilla from spreading widely within the NE bay of East Twin.  Hence, the decision to treat the entire NE bay of East Twin with low concentration SONAR for the 2025 season.

George then reviewed aquatic plant surveys from August 2024 which showed hydrilla was widespread within the NE cove, including in water up to 26 feet deep.  He compared this to a survey completed in August which showed three small plants exiting the marina.  Hydrilla was not found anywhere else within the NE cove of East Twin nor has it been found elsewhere in Twin Lakes. 

Geoge cautioned the group that while this is good news in terms of managing the risk of hydrilla spreading within the lake system, that ongoing treatments for the next several years are advisable based upon experience in other lake systems.  Hydrilla can lay dormant for many years in the sediment, and it is important not to declare premature victory.

George also noted that the SONAR treatments appeared to affect some of the native plants as well as one state listed species.  A full report will be compiled at the end of the season and submitted as part of the permitting process for the 2026 season. 

The meeting was opened for questions, and a robust discussion ensued.  Questions were asked about the probability of hydrilla spreading to lakes that do not permit boats from the outside to launch on their waters to the costs incurred by the TLA for last year’s treatment alone.  Many of the local lake associations in attendance discussed their approach to getting prepared for a potential hydrilla infestation.  CT DEEP provided some helpful advice to attendees.

Grant summarized some learnings from the TLA experience over the past three years including:

1. Prevention is key…keeping hydrilla out of a lake system is worth the time and investment and treatment is much more costly, and eradication is unlikely.
2. Frequent aquatic plant surveys by qualified personnel are vital both for surveillance purposes as well as to prepare for any permit request to CT DEEP.
3. Once found, the treatment options are limited. Our experience is that pulling plants by hand is not effective as they grow back in a matter of days.  Benthic barriers may be useful on small patches, but they are of limited value for larger beds.  All other options, including sterile carp, carry risks.  The TLA and our advisors believe herbicides are the best alternative for large infestations given today’s technology.
4. Spot treatments failed to stop the spread of hydrilla on East Twin in 2024. Each time we found a new hydrilla patch, by the time we received permission to treat this new area, the plant had grown to an extent where control was nearly impossible.  Hence, our decision to treat the entire NE bay of East Twin with low concentration SONAR for the entire 2025 season.  Based upon numerous aquatic plant surveys conducted over the summer, this strategy proved to be highly effective. 
5. Big hydrilla plants are hard to kill. At best, herbicides weaken the plant and prevent some of the end of year turions from being released.  Hence, we believe treatment when the plant is small early in the season is the most effective in terms of timing.  We found sprouting turions as of May 9^th in 2025 and the first SONAR treatment was applied on May 20th.