By Mike LaCrosse

BARNSTABLE (CBS) – Marstons Mills residents are upset toxic algae is invading their ponds again this summer.

Delia and her husband bought their home because it sits on Long Pond. It’s now closed to swimming because of cyanobacteria.

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“It’s kind of sad because there are a lot of young couples in the neighborhood who bring their children down here to play in the water because it’s easier than taking them to the ocean obviously. It’s safer,” said Delia.

Long Pond in Barnstable is one of several ponds closed due to cyanobacteria blooms. (WBZ-TV)

Long Pond is one of several closed in the town of Barnstable. Others are on the warning list.

“So we’re monitoring ponds with permanent beaches and ones that are in trouble for Cyanobacteria,” Town of Barnstable’s Coastal Health Resource Coordinator Karen Malkus-Benjamin said.

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Cyanobacteria blooms are also called blue-green algae. They can produce harmful toxins and cause serious illness to humans and pets.

“A regular person, if they were exposed to maybe a small amount, might feel nauseous or might be dizzy. It could vary,” Malkus-Benjamin said.

Two ocean beaches in Barnstable are also closed to swimmers because of another type of bacteria, possibly caused by wastewater. Veteran’s Beach and Rope’s Beach failed sample tests.

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“It’s really disappointing because it’s a very picturesque area, and, you know, from time to time, you’d like to maybe just put your feet in here,” said Nancy Pelland, of Barnstable.

Mike LaCrosse