After recent close calls and a death in 2014, the city plans to install warning signs around Prospect Park Lake to caution parkgoers from running into water covered by a grass-like sheet of duckweed and algae.

The decision came two days after THE CITY highlighted cases of children who accidentally ran into the murky water and nearly drowned as they played in the 526-acre Brooklyn park.

Parks Department staffers will put up signs along the lake’s 2.5 mile shoreline this week, according to Megan Moriarty, a department spokesperson. It was unclear, though, how many signs will go up or where exactly they will be placed. 

Parents say the area around the Boathouse is particularly dangerous because the main park pathway is nearby and there’s a grassy slope that leads right into the water filled with toxic blue-green algae. That’s where Ariella Deutsch’s toddler charged into the green grass-like duckweed-topped water on July 12. 

Deutsch, a lawyer, said it’s “great” the signs are coming, but urged the city to do more. 

“It’s not enough,” she said. “I doubt it is sufficient to prevent a tragedy in a jam-packed city in the middle of a pandemic where many people have few options for green space.”

Depending on their location, the signs might put parents “on notice” that it is a dangerous area, she added. 

Rich Gershberg, who was taking a walk with his 3-year-old daughter, Avery, said duckweed in the Prospect Park Lake was the “worst I’ve ever seen it,” July 21, 2020. Credit: Ben Fractenberg/THE CITY

But the grass near the Boathouse walkway, she pointed out, slopes downward and easily confuses kids who scoot right into the gooey water. 

“At the very least, that entry to the lake needs to be fenced,” she said. 

Her toddler, who became submerged in the gucky water, was rescued by her husband and an onlooker. 

Elona Litvintchouk, whose then-5-year-old son Yechial fell into the water in 2017, was also skeptical. 

“I think that’s great, but let’s hope they actually do it,” she said. “Years ago they said the same thing to me and never did it. There are probably tons more children it happened to that we don’t even know about.” 

A 2014 Tragedy

In 2014, the green grass-like duckweed and algae contributed to a toddler’s drowning in the 55-acre lake. The duckweed on top of the water and algae inside made it hard for rescuers to locate 2-year-old Ruhshona Kurbonova, who had wandered off with her 3-year-old cousin during a family get-together at the park.

An NYPD helicopter flew over the lake during the search in a desperate attempt to blow away the duckweed and thick algae. 

The Parks Department now uses a $140,000 weed harvester nicknamed “The Floating Goat” once a week to minimize the spread of the duckweed and water primrose. 

The Prospect Park Alliance uses the weed harvester known as “The Floating Goat” to help maintain the lake. Credit: Paul Martinka/Courtesy of the Prospect Park Alliance

The algae grows wildly in the summer and feeds on phosphorus that comes in with the municipal water that feeds the lake. It also chomps on the decomposition of other algae that bloom and die.

Last year, the Prospect Park Alliance, which handles park maintenance, announced it planned to install a natural filtration system, known as an ecoWEIR, to reduce cyanobacterial harmful algal blooms called CyaoHABS or HABS for short. 

Jennifer Cherrier, a Brooklyn College environmental sciences professor who invented and patented ecoWEIR described it as an “underground Brita system” that holds the incoming water about a foot below the surface of the soil and just underneath the plant root zone. There it undergoes a sort of natural cleansing to rid it of phosphorus from the city water supply. 

Construction on the $394,473 pilot program to be launched near the water feeding into the Prospect Park Dog Beach was delayed by the construction halt during the peak of the pandemic.

It is slated to be running soon, according to the Prospect Park Alliance. But it is not expected to have much of an effect on the water by the Boathouse, which is further away, and will require the removal of phosphorus already in the lake. 

An ‘Innovative’ Approach

“They are being really innovative and looking for solutions to solve this,” Cherrier said of the broader duckweed and algae problem. “They are looking for a long-term solution. Not a short-term solution where you just throw some chemicals into the lake.” 

After Kurbonova’s death, Brooklyn Borough President Eric Adams suggested the park deploy its weed harvester more frequently during the summer months when the green growth explodes. 

“We want to make sure we adjust to make sure we are safe,” he said at the time. 

After the latest near drowning, Deutsch’s husband, Andrew Kleinfeld, reached out to his office, citing that prior comment. 

The pathway leading to the water by the Boathouse slopes downwards and has “no fence or barrier or anything,” he wrote July 23. 

A constituent liaison for Adams wrote in email the next day that he’d follow up with the Department of Homeless Services and Department of Sanitation. 

The pathway leading to the water by the Boathouse slopes downwards and has ‘no fence or barrier or anything.’

Deutsch was confused by that response, noting the green space is overseen by the Parks Department. 

A representative for Adams said the case was “mixed up with another” and should have been referred to the Parks Department.

“Our constituent assistance unit handles hundreds of cases each week, and that high caseload, coupled with the system of working remotely, sometimes leads to human error,” said Jonah Allon, a spokesperson for Adams. “We thank the family for bringing this issue to our attention, and the Parks Department for committing to placing signage near algae blooms to warn Brooklynites of the hazards.”