Worcester's Coes Reservoir Herbicide Treatment Postponed

WORCESTER, MA — A portion of the Coes Reservoir in Worcester will soon get an herbicide application to kill invasive water chestnut plants.

The treatment was planned for Wednesday, but it was canceled late Tuesday due to a poor weather forecast.

When the time comes, crews will be out in boats at the north end of the reservoir applying the herbicide imazamox, also called Clearcast. The product kills plants by disrupting enzymes, but may also be harmful to unborn children, according to the National Institutes of Health. The risk to humans and animals goes away after the herbicide has been applied, according to the city.

"We advise all persons to discontinue using water from Coes Reservoir for irrigation of plants or lawns or watering livestock, and to keep clear of application boats for the duration of the day," the city said in a news release.

Although Worcester beaches won't officially open until Friday, the city is not closing the Coes Pond Beach for recreation. However, boating will not be allowed in the northern portion of the reservoir.

Coes Reservoir will reopen fully on Thursday. Any resident with questions about the herbicide can contact the Worcester Conservation Commission at either 508-799-8325 or greenworcester@worcesterma.gov.