Blue-green algae bloom alerts issued for these Central Florida lakes

Lake Ivanhoe is the latest lake to have blue-green algae

ORLANDO, Fla. – The Florida Department of Health has issued warnings in multiple Central Florida counties about harmful algae toxins found in different bodies of water.

This story was last updated on April 26 with the latest health alerts for blue-green algae.

Orange County

  • A health caution alert was issued on April 26 for Lake Ivanhoe in Orlando because of the presence of blue-green algae. The algae were found in a water sample on April 25. The public should exercise caution in and around the lake, according to the Florida Department of Health in Orange County.
  • The Florida Department of Environmental Protection has extended a health alert due to water samples collected on April 6 from Lake Mann near the Gilbert McQueen boat ramp. Environment officials said that unsafe concentrations of toxins are still present in the lake.

Seminole County

  • The Florida Department of Health issued a health alert for Lake Kathryn on May 12 in response to a water sample taken on May 5, which indicated harmful levels of blue-green algal blooms. Health officials urge the public to exercise caution around the lake.

What is blue-green algae?

Blue-green algae are a type of bacteria that is common in Florida’s freshwater environments. A bloom occurs when rapid growth of algae leads to an accumulation of individual cells that discolor water and often produce floating mats that emit unpleasant odors, according to the Florida Department of Health. According to health officials, sunny days, warm water temperatures, still water conditions and excess nutrients can all contribute to blooms.

Is it harmful?

It can be, to human health and ecosystems, including fish and other aquatic animals, according to the health department.

The public should exercise caution in and around areas where bacteria are reported.

For additional information on potential health effects of algal blooms, visit

What precautions should I take?

Residents and visitors are advised to avoid swimming, wading, using a watercraft or boating where there is visible algae bloom. Health officials say people who make contact with algae or discolored, smelly water should wash one’s skin and clothing with soap and water. Do not cook or clean dishes with water contaminated by algae blooms, officials said. Boiling the water will not eliminate the toxins.

Eating fillets from healthy fish caught in freshwater lakes experiencing blooms is safe, according to the health department. Fish fillets should be rinsed with tap or bottled water, guts should be thrown out and the fish should be thoroughly cooked. Do not eat shellfish in waters with algae blooms.

People should also keep pets away from the area as algae blooms are not safe for animals.

People can report symptoms from exposure to a harmful algal bloom or any aquatic toxin to the Florida Poison Information Center at call 1-800-222-1222. All other questions regarding concerns about blue-green algae blooms should be directed to residents’ respective county health departments.