Red tide causes massive fish kills that pollute coastlines and drive away tourists, costing local governments millions in cleanup costs.
Sparked by a naturally occurring organism called karenia brevis, once a red tide bloom starts there’s little people can do but wait for it to die off on its own.
But on Wednesday, three technologies that have cleared state and federal regulatory hurdles and are ready to scale up and use to kill red tide were on display at Mote Marine Laboratory in Sarasota.
While they are deemed safe for the environment, the cost of deploying them remains unclear.
Representatives of the companies involved declined to give dollar estimates, citing the vast differences in the size and the severity of a red tide outbreak as key variables.
They’ve been tested in labs and canals and marinas, but none have been used yet on a broad scale against red tide in a bay or the Gulf of Mexico.
Cleanup from red tide cost Florida about $14 million in 2018, a particularly bad year for the toxin, according to state officials. In Sarasota County alone, the parks department spent $224,410 on cleanup that year, a spokeswoman said.
Mote president and CEO Michael Crosby said the new technologies are the result of years of work between scientists and private companies to develop strategies to safely tackle the toxic blooms.
“It's not difficult to kill the algae that starts red tide,” said Crosby. “Give me a crop duster, fill it full of copper sulfate, spray the red tide, and you'll kill all that red tide. You'll kill everything else in the marine ecosystem as well.
“So our mantra is, with all of these technologies, none of them will do any greater harm to the environment than the red tide is already doing."
One of the technologies shown to reporters Wednesday was a biocide called CLEAR that is derived from a plant extract and could be sprayed by backpack, drone or boat.
“We have engineered particles. Some dissolve quickly, some more slowly. Some are neutrally buoyant. Some float, some sink,” said principal investigator Dana Wetzel.
It works by infiltrating the cell wall of the red tide organism and causing it to disintegrate. And CLEAR does not accumulate in the environment, she said.
“We can use this product in areas where there's fish and in shellfish harvest areas,” Wetzel added. “In eight hours, 97% of CLEAR is gone.”
Another, called Xtreme, made by Heartland Energy Group, is based on a disinfectant that’s already used on pig farms to kill viruses. It has also been used in freshwater to kill algae blooms. Company representatives said it was not harmful to clams that were treated in the same tank as red tide.
“It transcends different industries, so we use it in ag, we use it in the oil field,” said Heartland president Steve Rowley.
“We use it as a disinfectant to clean the buildings out. We use it to basically fend off really horrible diseases,” Rowley added, like African swine flu and a respiratory illness that can kill pigs, known as porcine reproductive and respiratory syndrome (PRRS).
A third technology comes in the form of a trailer mounted on a semitrailer and is known as Ozonix. It sucks up contaminated water through hoses and employs a series of devices that make tiny bubbles, which then explode red tide organisms, before funneling out cleaner water.
“This is completely chemical free,” said Steve McKenzie, lead technician with Prescott Clean Water. “We're now working on a 48-hour deployment plan with the Department of Environmental Protection where there could be a notice of a red tide bloom and we could be treating 48 hours after that.”
The field of red tide research has come a long way, but questions still remain about how to scale up the technologies and who will pay for them to be deployed.
Richard Pierce, a vice president of research at Mote, said he is not concerned about President Donald Trump’s move this week to pause federal loans and grants – which was temporarily blocked by a federal judge on Tuesday – and to reduce the size of government bureaucracy.
“Personally, I'm very much in favor of reducing our federal budget, and I think there's a lot of waste there, so I'm pleased to see him doing that,” said Pierce.
“The main problem is, who's going to pay for this once we have it all ready?”
Pierce suggested that county and municipal funding could be an answer, as well as revenue from tourism taxes.
“Who cleans up the dead fish? That costs millions of dollars," Pierce said. "We can avoid that if we use this first so I think there's a real economic benefit if people see that.”
Gov. Ron DeSantis signed a law establishing a collaboration in 2019 between Mote and the Florida Fish and Wildlife Conservation Commission after red tide cost the state some $2.7 billion in tourist revenue in 2018.
The work is the product of the Florida Red Tide Mitigation & Technology Development Initiative, funded by state and federal sources and tested at red tide lab facilities at the Mote Aquaculture Park, and in canals and marinas.
Florida provides a $3 million appropriation from the state’s general revenue fund each year for six years for a total of $18 million.
“We have looked at over 300 different approaches and methodologies. We've narrowed it down. We have nearly two dozen very diverse approaches,” said Crosby, who also said he is not concerned that Trump’s actions to reduce the federal bureaucracy could have an effect on this effort.
“In the end, it will require government approval for the deployments, both at federal and state levels, and that's why we're working very, very closely with all of the pertinent federal agencies as well as state agencies throughout this process. The state of Florida is behind this 100%.
“I worked in Washington, D.C., for over 20 years. It is one just mess of bureaucracy that slows everything down, and this is not something you want to slow down.”
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