Algae blooms in St. Johns River triggers new alert from health department

JACKSONVILLE, Fla. – The Florida Department of Health in Duval County on Thursday issued another warning over the presence of harmful blue-green algae blooms in the St. Johns River.

According to a news release, the alert was triggered based on water samples that were taken Sept. 23 - 27. The Health Department said the public should exercise caution in an around the St. Johns River, but put an emphasis on the following locations:

  • St. Johns River – Lions Club Boat Ramp
  • St. Johns River – St Johns Marina
  • St. Johns River – Canal to Marco Lake
  • St. Johns River – Mouth of Craig Creek
  • St. Johns River – Mouth of Goodbys Creek
  • St. Johns River – Yacht Basin, near Ortega
  • St. Johns River – South end Hart Bridge
  • St. Johns River – at Worth Dr. S
  • St. Johns River – Christopher Creek – below San Jose Blvd.
  • St. Johns River – Mandarin Point

Health officials say the public should exercise caution in and around the St. Johns River and those locations.

  • Do not drink, swim, wade, use personal watercraft, water ski or boat in waters where there is a visible bloom.
  • Wash your skin and clothing with soap and water if you have contact with algae or discolored or smelly water.
  • Keep pets away from the area. Waters where algae blooms are present are not safe for animals. Pets and livestock should have a different source of water when algae blooms are present.
  • Do not cook or clean dishes with water contaminated by algae blooms. Boiling the water will not eliminate the toxins.
  • Eating fillets from healthy fish caught in freshwater lakes experiencing blooms is safe. Rinse fish fillets with tap or bottled water, throw out the guts and cook fish well.
  • Do not eat shellfish in waters with algae blooms.

Less than two months ago, the health department issued an alert about possibly toxic algae at locations along the St. Johns River and Julington Creek in Mandarin.

What are blue-green algae?

Blue-green algae are a type of bacteria that is common in Florida’s freshwater environments. Abloom 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.

Some environmental factors that contribute to blue-green algae blooms are sunny days, warm water temperatures, still water conditions and excess nutrients. Blooms can appear year-round but are more frequent in summer and fall.

Are blue-green algae harmful?

Blue-green algae blooms can impact human health and ecosystems, including fish and other aquatic animals. For additional information on potential health effects of algal blooms, visit

Find current information about Florida’s water quality status and public health notifications for harmful algal blooms and beach conditions by visiting To report a bloom to DEP, call the toll-free hotline at 855-305-3903 or report online. To report fish kills, contact the Florida Fish and Wildlife Research Institute at 1-800-636-0511.

Report symptoms from exposure to a harmful algal bloom or any aquatic toxin to the Florida Poison Information Center, call 1-800-222-1222 to speak to a poison specialist immediately. Contact your veterinarian if you believe your pet has become ill after consuming or having contact with blue-green algae-contaminated water.

If you have other health questions or concerns about blue-green algae blooms, please call the Florida Department of Health in Duval County at 904-253-1280.

About the Author:

Joy Purdy co-anchors the 5:30 and 6:30 p.m. newscasts with Tarik Minor and the 11 p.m. weeknight newscasts with Kent Justice.