Caloosahatchee slimed: Seasonal nuisance or toxic warning?
As a plume of foul-smelling, pea-green water tainted by potentially toxic cyanobacteria flows down the Caloosahatchee, state and county officials are silent on whether people should stay out of the river.
The U.S. Army Corps of Engineers closed the beach at W.P. Franklin Lock on Friday, and Lee County Utilities' Olga Water Plant has stopped pulling from the river until conditions improve, said county spokeswoman Betsy Clayton.
How bad the river's slick will get and what its impact will be is an open question.
State: Lake Okeechobee water to be sent south to Everglades
What isn't in doubt is that such blooms are fed by pollution washing into the river from its watershed and Lake Okeechobee, where more than 30 square miles are covered with the stuff.
Initially spotted last week along the LaBelle, Alva and Olga shorelines, the cause of the green water is a sudden bloom (not in the sense of flowering, but of the proliferation of "dense surface scum," as the U.S. Environmental Protection Agency puts it) of the cyanobacteria Microcystis, also called blue-green algae.
It’s moving steadily downriver.and was detected west of Interstate 75 last week by underwater sensors that monitor's the river's condition.
Rick Bartleson, research scientist for the Sanibel-Captiva Conservation Foundation, which operates the sensors, identified Microcystis under a microscope, but can't yet say if the bloom is producing toxins.
"Our Beautiful Island and Fort Myers (sensors) are seeing some of that bloom going by," wrote Bartleson in an email "and also the increased turbidity from the high flow."
Meredith Maloney recently bought a kayak, but now hesitates to use it. “I live within a stone’s throw of the Caloosahatchee in North Fort Myers, and am reluctant to use the nearest launch and be exposed to its waters. I'm pretty down in the dumps about it and about the fact that I must travel greater distance to find more suitable, less polluted waters.”
The organism occurs naturally in Southwest Florida’s fresh water. "We have had cyano blooms in the (Caloosahatchee) almost yearly," Bartleson said. When it blooms heavily, though, it can mean trouble.
Earlier this month, South Florida Water Management District staff noted a large algae bloom and a fish kill in Lake Okeechobee. A water sample showed a Microcystis bloom in the same place. Though commonly referred to as algae, there are many there are many species of cyanobacteria, including Microcystis, all of which lack cell nuclei.
Their toxins can cause problems in people and animals ranging from itchy eyes and sneezing to liver failure and even death, if ingested in significant amounts. They can also kill fish and other water creatures.
Alva resident Nancy Hetrick Lee, who lives on the river, wonders if she’s already seeing casualties of the bloom. “I don't know if this is from the green algae, but we've seen two dead turtles floating down the river this week” — the first she’s spotted in 16 years of living there, she says.
Reducing pollution in the river would reduce the frequency and severity of the blooms, says the Conservancy of Southwest Florida's Jennifer Hecker. "The sadly routine algae outbreaks have resurfaced and will continue to do so until we buy additional land south of Lake Okeechobee needed to cleanse and redirect the damaging polluted discharges currently coming into the Caloosahatchee back to the Everglades, where they historically flowed and belong."
Sanibel-Captiva Conservation Foundation keeping tabs on water quality
When blooms are reported, multiple state agencies respond as a team, with Florida's Department of Environmental Protection in charge of collecting samples to analyze.
Staffers took water Tuesday from the river near Alva and from Billy’s Creek, said spokeswoman Dee Ann Miller.
"The samples will be sent to the DEP lab in Tallahassee for algal bloom identification and toxin analysis," said Miller, who expects results before the end of the week.
In the meantime, Lee County's health department "has not issued an advisory related to potential health impacts of algae in the Caloosahatchee River ..." wrote administrator Angela M. Swartzman in an email.
She emphasizes the response is necessarily a careful, multi-step process, and much as the public might like an instant answer, that's not possible. Swartzman likens it to a physician seeing a skin lesion that to a trained eye, looks like melanoma. But without clinical confirmation, it would be irresponsible to make such a declaration.
The same scientifically systematic approach governs agencies' approach to events that potentially affect public health. Once the test results are available, if it turns out the water is dangerous, then the health department takes the lead in warning people, including posting signs at beaches and other waterfront areas, Swartzman wrote. The state maintains an online mapped database of reported blooms.
For his part, Bartleson cites a bit of common sense: "When in doubt, stay out."