Natick rejects chemical use on weeds in Lake Cochituate

The town of Natick has told the state that it's open to any technique to kill the weeds that are taking over parts of Lake Cochituate -- as long as chemicals are not used.

The Natick Conservation Commission voted unanimously last week to deny the state's request to use herbicides to treat the fast-growing Eurasian milfoil that is clogging the lake.

Instead, town officials gave the go-ahead to use biological methods such as introducing weed-eating weevils, or other methods such as pulling the weeds out by hand. The commission has asked the state to report quarterly on its progress.

''It's our responsibility to look into all options before we resort to chemicals," said commission chairman Matthew Gardner. ''What the state needs to do now is develop a broad-based program that has a variety of techniques and realize there is no magic bullet. Milfoil is not going away, but it can be managed."

Vanessa Gulati, a Department of Conservation and Recreation spokeswoman, said the agency would review orders approved by the Framingham, Wayland, and Natick conservation commissions before developing a plan. The lake is in those three communities.

The state sought to use chemicals in Wayland and Natick, but not in Framingham. Wayland directed the state to try all other options first, while Natick rejected any use of chemicals.

''Within the next few weeks, we should have a plan developed based on those orders," Gulati said.

She said the state will be conducting a full vegetation survey to determine the extent of the problem. Milfoil has spread rapidly in some areas, making it difficult to boat and swim.

The state also has the option of appealing the rulings; Gulati said the agency hasn't decided whether to do so. The agency has 10 days after the orders have been signed by the town boards to appeal.

The state wanted to use herbicides because officials felt chemicals would be the most effective way to kill the milfoil. The state proposed using Sonar, whose active ingredient is fluridone.

Gulati said the state stands by US Environmental Protection Agency studies that have shown that fluridone is safe in drinking water. However, Natick health officials raised concerns about the safety of chemicals, pointing out that the lake is connected to ground water that feeds nearby town wells.

Given the uncertainty, Gardner said it made sense to explore other alternatives first.

It was also clear, Gardner said, that the community opposed the use of herbicides. The advocacy group Protect Our Water Resources packed each commission meeting and provided expert testimony and research opposing chemicals. Other than state officials, there were few in Natick who spoke out in favor of chemical use, Gardner said.

Gardner said the state could consider pulling the weeds by hand or using circulators, machines that stir up the water, which he said have proven to kill the milfoil. Another option is introducing weevils, aquatic insects that feed on the weed.

''We saw intriguing, not compelling or convincing evidence, that they can be effective," Gardner said.

Gardner said the town is eager to work with the state.

''They will find us to be very willing partners to devise solutions that work," Gardner said.

''We're very open. These are our lakes and we're all in this together."

Carole Berkowitz, chairwoman of Protect Our Water Resources, said she also hopes the group can have a positive working relationship with the state. She said many members of the group would be willing to volunteer to help. ''We will certainly try to support them in any way possible," she said.

Berkowitz said the group hopes the state considers the use of weevils in Pegan Cove. She said it would be unwise to use circulators there because pollution from Natick Labs has settled on the bottom of the lake in that area.