Tortured water: Noxious blue-green algae returns to Prospect Park Lake for fifth year in a row

Dogs’ swimming hole in Prospect Park is toxic
Ewwww: Algae in Prospect Park Lake makes its waters dangerous to dogs and their human friends.
Photo by Jason Speakman

The green reaper is back!

Toxic blue-green algae is blooming on Prospect Park Lake for the fifth-consecutive summer, according to state environmental sleuths, and stewards of Brooklyn’s Backyard are banning pooches from its water because the goop can be fatal to dogs and harmful to their humans.

Inspectors with the state’s Department of Environmental Conservation tested the lake earlier this month, and the results confirmed its widespread contamination with blue-green algae, or cyanobacteria, which blooms during warmer weather and produces two types of toxins when it does.

One toxin affects the liver, and can lead to symptoms including vomiting, seizures, dark poo, and diarrhea within 24 hours of being ingested by furballs, according to the director of a Park Slope veterinary clinic, who said the toxin, if left untreated, could cause liver failure and death within days.

The algae also produces a neurotoxin that can affect pets almost instantly, causing symptoms that include severe drooling and tearing, muscle spasms, and tremors. And in extreme cases, animals can die within an hour of ingestion, said the Slope vet, who encouraged bringing Fido for a check-up if he drinks from the lake or exhibits any symptoms.

“It’s better to be safe than sorry in those instances,” said Verg North’s Dr. Brett Levitzke. “The prognosis for true ingestion of either toxin is so poor, especially the neurotoxin.”

Humans, while less likely to lap up the lake’s wet stuff, are equally susceptible to the algae’s toxic byproducts, which can also show up in the form of a nasty skin rash — so locals who want to play it safe should avoid catch-and-release fishing and boating there to steer clear of contaminated water.

And the good news for Prospect Park–loving mutts and their masters is that the algae has yet to turn up at Dog Beach, which remains open for hot dogs looking to cool off, according to a spokeswoman for meadow conservancy the Prospect Park Alliance.

The blue-green algae is in part caused by phosphates in the city’s water supply, which feeds the lake, and Alliance leaders are working with state environmental inspectors to take weekly tests of the water, conservancy spokeswoman Lucy Gardner said.

In February 2017, the state awarded the Alliance a $390,000 grant to fund a study ahead of the installation of two natural-filtration systems meant to siphon algae-causing phosphates from city water before it enters the lake.

But Gardner could not provide an update on the study or the filtration systems’ installation, and said her Alliance colleague overseeing the work was unavailable to comment.

Earlier this month, park stewards debuted a new boat that cleans some unwanted plant life from the lake, but does nothing to combat the algae, Gardner said at the time.

Reach reporter Colin Mixson at cmixson@cnglocal.com or by calling (718) 260-4505.

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