APA approves herbicide in Warren County’s Loon Lake

RAY BROOK – The state Adirondack Park Agency voted unanimously Friday to approve the controversial use of a chemical herbicide to kill invasive plants in a Warren County lake.

The town of Chester plans to disperse 1,500 gallons of Renovate OTF, which goes by the chemical name triclopyr, in the southeastern corner of Loon Lake this spring. The project had been approved Thursday by the agency’s Regulatory Programs Committee.

The herbicide would be used to kill Eurasian watermilfoil, which has clogged waterways across the Park and been a nuisance to boaters and swimmers. The town and the Loon Lake Park District Association are hoping the one-time application of the herbicide in a 15-acre bay near the lake’s boat launch will help reduce the long-term costs of removing milfoil, which have topped $260,000 there over the past 10 years.

“It will allow us to gain more control over the rest of the lake,” said Edward Griesmer, the association’s president. “The use of Renovate, we believe, will allow us to deal with it in a more effective way.”

The Adirondack Council, an environmental group, had called for a public hearing on the use of the chemical, citing the die-off of large numbers of snails when Renovate was used for the first time in the Park in Lake Luzerne in 2011.

APA staff said during a presentation Thursday that the treatment is taking place in the early spring before most aquatic plants in the lake begin to sprout. Staff also said there was no “conclusive” explanation for what caused the snails in Lake Luzerne to die all at once and that a study has found the species has been shown to die off naturally in large numbers in other Northeast lakes.

APA Commissioner Richard Booth suggested the agency host a general public hearing on the use of triclopyr in Adirondack lakes, saying he expects to see similar requests in the future from other local governments and lake associations dealing with invasive plant problems.

The herbicide is scheduled to be applied to Loon Lake via boat on May 13. A large curtain will be spread 600 feet across the lake to prevent the chemicals from being diluted by water outside the treatment area. Monitoring sites will also be set up, no swimming will be allowed until at least three hours after the treatment, and the use of lake water for drinking or consumption won’t be allowed until the chemical’s concentration falls below a certain level.

Gerald Delaney of the Adirondack Park Local Government Review Board thanked the agency for approving the use of the herbicide. Review Board Executive Director Fred Monroe, who is supervisor of the town of Chester and lives on Loon Lake, recused himself from Thursday’s discussion of the project.

Contact Chris Knight at 518-891-2600 ext. 24 or cknight@adirondackdailyenterprise.com.