The New Hampshire Department of Environmental Services is warning those who visit a park in Hopkinton of a bloom of cyanobacteria that might produce health concerns.
The department released the advisory about a bloom at the Elm Brook Park Beach on Tuesday. It says people and pets should avoid contact with the water in places where the lake has surface scum or green streaks.
The Concord Monitor reports the warning is not based on a toxin evaluation, but officials say the advisory is a precautionary measure for short-term exposure.