Herbicide Planned For Quechee Lake

Valley News Staff Writer
Monday, April 16, 2018

Quechee — Members of the public have until Friday to comment on a proposed state permit that would allow the Quechee Lakes Landowners Association to use a chemical herbicide to treat invasive milfoil on its privately owned lake near the banks of the Ottauquechee River. 

Association officials indicated this week that they are continuing to work on plans to restore public access for Hartford residents to Lake Pinneo, a 52-acre lake built on a thick plastic liner. But they’ve also expressed concerns that an outbreak of Eurasian milfoil could render the water body virtually unusable.

For months, they have sought a green light for the use of an herbicide from the Vermont Department of Environmental Conservation. The DEC’s Watershed Management Division has drafted a permit and made it available for public inspection and comment, based on a permit application that was prepared with the guidance of SOLitude Lake Management, a Shrewsbury, Mass.-based firm that did work at Lake Pinneo in the aftermath of Tropical Storm Irene in 2011.

In 2012, the company noted, there was no Eurasian milfoil in the lake, but by the time of a 2016 survey, the water-choking weed — known for its ability to harm ecosystems and ruin recreational opportunities — was present at three-quarters of its testing sites on the lake.

“Left untreated, milfoil will choke the life out of Pinneo and that means limited swimming, fishing and boating for anyone who wants to use the lake — QLLA members and Hartford residents alike,” said QLLA President Craig Allsopp on Monday.

Last month, Allsopp said that, in 2017, the organization spent “thousands of dollars on divers and mechanical harvesting, but the milfoil is getting worse.”

In its permit application, the company proposes using a total of 2.5 gallons of Sonar over the course of four treatments, to be applied during a 90-day period beginning in early May. The plan calls for the chemical concentration to be no more than five parts per billion; a 2008 study commissioned by the USDA found that adverse health effects associated with fluridone, the active ingredient in Sonar, are triggered only in significantly higher concentrations.

“The risk to the environment and public health is so minimal that only inconsequential harm is expected to occur as a result of the proposed control activity,” according to the draft permit currently available for public review on the Agency of Natural Resources website. The agency asks interested parties to email comments to the Lakes Permit Program at ANR.WSMDShoreland@vermont.gov.

Josh Mulhollem, the DEC’s aquatic invasive species management coordinator, said the treatment is likely to be only part of the solution to controlling milfoil.

“Eradication is out of the question,” Mulhollem said. “You’re not able to get the seed bank. You have a drastically reduced population but most active management plans that have a chemical component have maybe an every three-year, or five-year, treatment regimen.”

Mulhollem said there are a handful of active permits in the state that allow use of aquatic chemical herbicides at any given time. In some cases, Mulhollem said, regulators determine the risk outweighs the public benefit — in February, the DEC denied a similar permit application for the Lake Iroquois Association in Hinesburg — but in other cases, chemical agents make sense.

“There’s an upside and a downside,” Mulhollem said. “Some folks are anti-chemical regardless of whether other entities have weighed in and treatments are within state limits.”

In this case, Mulhollem said, “by our definitions, it’s basically a private water body. It’s completely controlled by one landowner and they’re also able to control the outflow, so that works in their favor. But if the treatment occurs and you have a freak flood event, there’s potential for it to go downstream and into the Ottauquechee River. The permit takes that into account.”

The application acknowledges that the treatment likely will knock back a handful of native plant species currently found in Lake Pinneo, including the nodding waternymph and sago pondweed, but says “these plants generally recover within 1-2 years of the treatment.”

Mulhollem said the lake management company has asked for modifications to the permit as drafted, and that discussions with DEC staff are ongoing.

The total cost of the five-year eradication program, which includes hand-pulling and suction harvesting as well as another round of chemical treatment in 2021, is estimated at $70,700. If approved, the permit will only authorize the 2018 chemical treatment.

Because the permit closes the lake to swimming for only 24 hours after each Sonar treatment, it is unlikely that it would significantly impact usage of the 52-acre lake this summer. It typically opens for the season on Father’s Day, which this year falls on June 17.

The permit now under review finds that the purpose of the project is “to support public recreational use of the lake.”

In February, QLLA moved to develop a plan to allow Hartford residents access to the lake, which is a condition of the man-made lake’s original 1974 Act 250 permit from the state’s District 3 Environmental Commission.

Not realizing its legal obligation, QLLA three years ago revoked public access to the lake during a disagreement with the town; once the original permit resurfaced, Allsopp said access would be restored this summer, but the exact terms and costs of access have not been determined.

“The committee I appointed has met and will be making its recommendations for town access to the QLLA Board soon,” Allsopp said. “I see no reason why Hartford residents won’t be able to use the lake this summer.”

Matt Hongoltz-Hetling can be reached at mhonghet@vnews.com or 603-727-3211.