From the Westford Board of Health: Portions of Nabnasset Lake, Westford, will be chemically treated with a USEPA/MA registered aquatic herbicide on Wednesday, June 11. This treatment is targeting the invasive and non-native curlyleaf pondweed and milfoil weed species. The entire lake will be closed to all water uses (including swimming, fishing and boating) on the day of treatment. These water uses may resume on Thursday morning, June 12. Use of the lake water for drinking, irrigation (watering plants of any kind), watering livestock (i.e., cattle, horses, etc.) is prohibited for five days, commencing on the day of treatment. Pets or wildlife that may drink the lake water will not be harmed. 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 DEP and an Order of Conditions from the Westford Conservation Commission. Aquatic Control Technology, Inc., of Sutton, is the State Licensed Company that will perform the work.