Town officials are asking residents and their furry friends to stay away from Rainbow Reservoir in Windsor.
They say this is due to the presence of a cyanobacteria bloom in the water, which can cause mild skin irritation and illness.
This reaction can occur when a person or animal ingests, inhales, touches, or comes into direct contact with the algae.
The blue-green algae has not compromised any of the nearby groundwater wells, according to town officials.
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Anyone with questions or concerns are being asked to contact the Windsor Health Department at 860-285-1823.
Additional information on algae blooms can be found here.