There is no swimming at Lake Pocotopaug in East Hampton after routine testing showed elevated levels of blue-green algae.
The Chatham Health District posted results of testing of water sampled on July 24 and found dangerously high levels of the algae, prompting a closure of swimming areas at the lake.
Blue-green algae is not harmful in normal circumstances, but can be dangerous during an algae bloom – a rapid increase in the amount of algae, according to the Centers for Disease Control. A bloom can caused by a combination of warmer water temperatures and high nutrient concentrations that allows the algae to spread.
The algae can porduce toxins that can be poisonous to humans, pets and wildlife.
The health district regularly tests the water and will advise when the water is safe to swim in.