Water samples taken this week off Manatee County showed low to very low levels of the organism found in Red Tide, the state said.
It is the first sign of Red Tide in Tampa Bay, a discovery that amplifies concerns that contaminated water pumped into the estuary from the old Piney Point phosphate plant property could fuel a bloom.
The presence of the Red Tide is “not thought to be a direct result of the Piney Point discharges,” the Florida Department of Environmental Protection said in a statement. “However, elevated nutrients have the potential to exacerbate these algal blooms, and increased sampling is ongoing.”
Red Tide has tormented Florida’s Gulf Coast before. Bad blooms can cause fish kills and breathing trouble for people along the shore. The state environmental agency said no fish kills have been reported in the area as of Thursday.
A sample taken from lower Tampa Bay, near Anna Maria Island and Bradenton, showed low levels of the organism that makes up Red Tide on Wednesday, according to the Florida Fish and Wildlife Conservation Commission. The agency describes low concentrations as capable of prompting respiratory irritation, possible fish kills and in some cases shutdowns for harvesting shellfish.
Two other nearby samples from this week showed “very low” concentrations.
Other samples pulled from Tampa Bay, including closer to Port Manatee — the site of the Piney Point discharges — have not shown troubling levels of Red Tide, according to state reports.
A leak earlier this month from a large wastewater reservoir on the old fertilizer plant land touched off fears of a catastrophic flood of polluted water in Manatee County. That did not happen, but the Department of Environmental Protection allowed the property owner to discharge the water into Tampa Bay through the port.
About 215 million gallons of polluted water, which regulators said contained elevated levels of nutrients like nitrogen and phosphorus, were pumped to the bay, according to the state.
Nitrogen is a specific concern for environmentalists and anglers because it can serve as fuel for algae. Before Thursday, scientists said some algae were growing around the discharge area, but early signs indicated the organisms are not toxic.
Red Tide, if it meets with the nutrient plume from Piney Point, could be a different story. A devastating bloom between 2017 and 2018 led to massive fish kills and kept people away from beaches along the Gulf Coast. Many tons of dead marine life washed up around Pinellas County.
Red Tide has dogged counties south of Tampa Bay in recent months. Health officials last week issued warnings about elevated levels in Sarasota County.