Department of Environmental Protection finds blue-green algae in Moorings Bay

Department of Environmental Protection finds blue-green algae in Moorings Bay

Lisa Conley, Naples Daily NewsPublished 4:28 p.m. ET June 14, 2019

The Florida Department of Environmental Protection has detected blue-green algae in Moorings Bay in Naples.

Stephanie Molloy, the city's natural resources director, said the algae originated in Swan Lake, which discharges into Moorings Bay.

Like several lakes throughout Naples, Swan Lake, near the intersection of Park Shore Drive and Crayton Road, is privately owned, which limits the city's ability to conduct water quality testing on it, Molloy said, but city staff has been working with the lake's owners to try to alleviate the situation.

"City staff have inspected the aerators in Swan Lake to ensure they are working," she said. "The city is working diligently with residents and their lake management company to monitor and mitigate this."

Molloy said the toxin levels from the algae in Moorings Bay are low — 1.7 micrograms per liter near the discharge from Swan Lake — which means the algae is less likely to pose an environmental or health risk.

Health department officials could not be reached for comment Friday afternoon."The level of microcystin toxin in the Moorings Bay sample near the discharge from Swan Lake is well below the U.S. Environmental Protection Agency’s recommended recreational swimming advisory level of 8 micrograms per liter," she said. "I would expect that other areas in Moorings Bay would have much lower, likely undetectable, or zero levels of toxin, as the further away from the discharge you get mixing and dilution."

The view of Moorings Bay from Park Shore Marina in Naples on Tuesday, Jan. 19, 2016. (Dorothy Edwards/Staff) (Photo: Staff)

That mixing and diluting also makes it unlikely that the blue-green algae could spread across the bay like it did on the Caloosahatchee River last summer.

"Moorings Bay is well mixed with seawater coming in from the Gulf, and these freshwater cyanobacteria don't survive long in saltwater," Molloy said.

However, when the bacteria starts to die off, it can result in a sludge that can be harmful to people and pets, Molloy said, so the city distributed a notice to all properties on Swan Lake. The Department of Health also posted notices near Moorings Bay. 

Swan Lake was the subject of debate at a recent city council workshop. Council approved spending $9.5 million in 2019-20 fiscal year on projects aimed at improving water quality, including lake restoration.

City Councilman Ray Christman said the presence of blue-green algae in Moorings Bay is "a troubling indication of the extent of severity of our water problems."

Christman also said the city needs to conduct a comprehensive analysis of its 28 lakes to know the extent of work that needs to be done.

"Probably the aspect of our water quality challenges that we’ve dealt with the least well in last 10 to 20 years is having a strategy and a plan for cleaning up these lakes," he said Friday.

"We don’t have a plan or strategy yet and increasingly clear we need to have one. I don't even know that we have a good current assessment of our lakes (so) the sooner we can get that done the better."

Councilman Reg Buxton also said the city needs to start taking action to fix its lakes.

"I have been a strong advocate for us to clean all the lakes now rather than later," he said. 

He also added that it's encouraging that the DOH is taking more of an active interest in monitoring harmful algae. 

"Last summer when we had the red tide and (harmful algal bloom) breakouts, it was almost impossible to get DOH to put out an advisory," Buxton said. "Local DOH would kick the decision to the state and it seemed to die there."

DOH issued several tips about interacting with algae blooms, including not swallowing water with algae blooms nor swimming or wading in it.

Keep pets away from algae mats. Pets have been sickened and killed after drinking contaminated water or licking algae off their fur.

Health officials warn to not use personal watercraft, ski or boat in areas with severe algae blooms.

Do not fill a pool or use an outdoor shower with water sources that have algal blooms. Fillets from healthy fish caught in freshwater lakes affected by a bloom are safe to eat.