Nab Lake Closed Thursday for Pesticide Treatment

Nabnassset Lake will be closed Thursday so workers can treat it with a pesticide.

The Nabnasset Lake Preservation Association authorized the copper sulfate pentahydrate treatment. The chemical attacks “nuisance” aquatic vegetation and algae blooms. The lake will be closed to all uses—swimming, fishing, and boating—Thursday. It will reopen as usual Friday at 8 a.m.

The state Department of Environmental Protection says copper sulfate pentahydrate is not harmful to humans under most conditions.

“Generally speaking, the only health concern involving copper sulfate involves the potential acute eye and skin irritation for workers handling the algaecide,” the department said.

The treatment will be done by Aquatic Control Technology of Sutton.

Here’s a notice from the town about the spraying:

Portions of Nabnasset Lake, Westford, will be chemically treated with Copper Sulfate Pentahydrate on Thursday, July 31st, 2014 at/after 1PM.

This treatment is targeting the growth of nuisance aquatic vegetation and/or potential algae blooms. The entire lake will be closed to all water uses(including swimming, fishing and boating) for the remainder of the day of treatment. Use of the lake water for drinking, irrigation (watering plants ofany kind), watering livestock (i.e., cattle, horses, etc.) is prohibited. These water uses may resume on Friday morning, August 1st, 2014 at 8:00 AM.The lake shoreline will be posted with printed signs warning of these restrictions in advance of treatment.

This work is being performed for the Nabnasset Lake Preservation Association in accordance with a License to Apply Chemicals issued by MA DEPand an Order of Conditions from the Westford Conservation Commission.

Aquatic Control Technology, Inc., of Sutton, MA is the State Licensed Company that will perform the work.

Photo credit: File