With temperatures reaching the 90s in many parts of the state on Monday, swimming would be the perfect way to cool off.
One popular lake in East Hampton is closed because of the large amounts of algae.
The type of algae found at Lake Pocotopaug could last until early fall, and the reopening of the lake depends on when levels go back to normal.
“It's really a bummer because we wanted to cool off and play in the sand. So now we will just play in the sand," said Sherrie Hansen, who drove from Rocky Hill to go swimming at the lake but then realized it was closed. “It tends to happen at least once a year so it’s disappointing,"
There were ‘No Swimming’ signs posted since the beginning of August because of the high levels of blue-green algae growing in the lake.
This type of algae blooms in summer and early fall and usually looks like pea soup.
It could be harmful and give swimmers a skin rash or respiratory problems.
Experts were out on the water on Monday taking samples.
Officials said they will be testing and monitoring the levels every week.
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