Algae bloom in Palatka, FL 4/2019 | Photo by Sam Carr

Attend one of our Know Your Green | Evening Talks:
DeLand | June 26

Invite us to come speak to your neighborhood or civic group on algae. Email to set up a Know Your Green talk.

Algae bloom season is already upon our St. Johns River. Since mid-April, St. Johns Riverkeeper has received dozens of reports from Lake George and Palatka and all the way to Jacksonville. Our team is saddened by the images flooding our communication channels of the green muck coating our River. This early start could potentially be a sign of worse blooms to come as sunny days, higher temperatures, and rain events occur more frequently.

Nutrients? Aren’t those good for the River?
Algae blooms are visible symptoms of sickness and too much nutrient pollution in our waterways. Nutrients like nitrogen and phosphorus are naturally occurring in our environment; however, in excess, they can undermine the ecological integrity of our waterways by depleting oxygen from the water, which negatively impacts plankton and causes fish die-offs, and hurting submerged grasses by blocking adequate sunlight. The River’s entire food web becomes severely harmed.

Impact to Us
Algal blooms can be highly toxic and can make us and our pets sick. Exposure to toxic algae can cause short term respiratory and skin issues as well as long term damage to the nerves and liver. If citizens spot what looks like bright green paint-like, scum on the surface of the water, they should steer clear. Do not recreate, boat, swim, or fish near an algae bloom.

So, where are all the excess nutrients coming from?
Some of the major sources of nutrient pollution (phosphrous and nitrogen) in the St. Johns River:

  • The application of sewage sludge (also known as biosolids) on agricultural lands surrounding our River’s Headwaters at Blue Cypress Lake.
  • Fertilizer run-off from agricultural, urban, and residential lands.
  • Malfunctioning septic tanks can leak sewage into our River and not all nutrients are absorbed or filtered in properly functioning septic tanks.
  • Industrial wastewater discharge and sewage spills.
  • Aquatic spraying.
  • Reclaimed water
  • Atmospheric Deposition

Where can I find the locations of recent algae blooms?

Before you get out on the water, visit the Florida Department of Environmental Protection’s website to see an ineractive map of algae bloom samples and results in our waterways at

Health Impacts

Toxins produced by algae blooms can cause rashes, stomach cramps, nausea, diarrhea, and respiratory irritation. High exposures of toxin can affect the liver and nervous system. If skin contact occurs, wash off immediately and thoroughly with clean water and soap.


  • Avoid scummy, foamy water where algae blooms are present (Heavy blooms are often bright or pea green, occasionally with a scum that looks almost like paint)
  • Don’t cook with, eat fish from, or ingest scummy water
  • Do not let your pets drink from affected waters
  • Don’t eat fish that look unhealthy
  • Do not swim in, jet ski over, or play near scummy water or blooms


There is no standard duration for a bloom and no way to determine visually whether a bloom is toxic.
• Report blooms to the Florida Department of Environmental Protection at or call toll free at 1-855-305-3903.
• Email with photos, time, date and location.
• To report fish that are either dead or sick, contact the Fish Kill Hotline 1-800-636-0511.

The Governor recently created a Blue-green Algae Task Force. However, it appears that the focus will primarily be on “Lake Okeechobee and the downstream estuaries.”
Urge the Governor to …
(1) ensure the Task Force addresses the needs of ALL of Florida’s waters, including the St. Johns, and
(2) focuses on stopping pollution at its source.
Call (850) 717-9337 or go to

Let them know that you are disappointed that the Florida Legislature failed to pass legislation to prevent sewage sludge and other nutrient sources from polluting our waterways. Tell them to get the job done next session by stopping pollution at its source. Find your Legislators

Tell your Mayor, City Council, or County Commissioners that we need to enact stronger fertilizer ordinances and enforce the ones we have! Let’s lead by example in our parks and homes to stop pollutants from reaching our creeks, lakes, canals, and waterways.

DON’T FEED THE ALGAE. Eliminate or reduce your use of fertilizer and reduce your impact on the health of our river. Learn how to live a more River Friendly lifestyle.

EDUCATE yourself and others by attending one of St. Johns Riverkeeper’s educational programs and events.

SPREAD the word! Share what you know with your friends and family and encourage them to be more River Friendly. Follow us on Facebook.