8 Westchester, Putnam beaches are closed due to harmful algae blooms. What to know

Some Westchester and Putnam beaches are closed because of harmful algae blooms in swim areas.

A Westchester health department news release said it's closed these Mohegan Lake beaches, the only Mohegan Lake ones it regulates:

• Mohegan Colony Association
• Mohegan Beach Park District

In Putnam, according to the county health department website, six beaches have been closed at various points since July 2 for algae blooms:

• North Beach, at Lake Peekskill, was closed starting July 7
• Barger Pond, in Putnam Valley, was closed starting July 6
• Singers Beach, in Putnam Valley, was closed starting July 6
• Carraras Beach, at Lake Peekskill, Putnam Valley, was closed starting July 5
• Jackson Beach, at Putnam Lake, Patterson, was closed starting July 2
• Warren Beach, at Putnam Lake, Patterson, was closed starting July 2

In Westchester, “The decision to close these beaches is a precautionary measure to ensure the safety and health of the public,” Dr. Sherlita Amler, county health commissioner, said in the statement. “Harmful algae blooms are more prevalent during hot days when water temperatures rise, leading to increased bacteriological growth rates.”

Of interest:Keep cool during the heat wave at Lower Hudson Valley pools, beaches and cooling centers

When will Westchester beaches reopen?

To reopen, algae must be fully cleared from the swim area, the Westchester release said, then water samples are analyzed.

Harmful blooms are the rapid growth of algae or cyanobacteria in water, according to the Centers for Disease Control and Prevention. "Going in or near water with a harmful algal bloom can make you and your animals sick. Stay out if water looks discolored, has scum, or smells bad," the CDC said. Some blooms make toxins that can sicken people and animals.

On the water surface, blooms can resemble foam, scum, mats, or paint. They can grow beneath water as well, so some blooms can be difficult to spot.

For Westchester beach closing/opening updates, go to the county's website.

For Putnam, check out updates here.