HILLSBOROUGH COUNTY, Fla. – Health officials in Hillsborough County are urging the public to stay out of Lake Thonotosassa following the discovery of harmful blue-green algae toxins. The Florida Department of Health (DOH-Hillsborough) issued a formal health alert on Monday, March 16, 2026, after water samples taken late last week confirmed the presence of the bacteria.
The alert was triggered by a specific water sample collected on March 12. Local authorities are now advising residents and visitors to avoid any activity that involves direct contact with the water, including swimming, wading, or using personal watercraft.
“Do not drink, swim, wade, use personal watercrafts, or come into contact with waters where there is a visible bloom,” the department stated in its release. Officials also warned that boiling the water is ineffective, as it does not eliminate the toxins…