St. Johns River Water Management District News Release
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Teresa Monson:(904) 730-6258 (Office) or (904) 545-5064 (Cell)

District launches informational web page on water quality, algae in lower St. Johns River

PALATKA, Fla., May 15, 2014 -- The St. Johns River Water Management District today launched a new page on its website ( that will provide regular updates on water quality in the Lower St. Johns River Basin in northeast Florida, including information about projects to restore and protect the river system, significant algae blooms when they occur, and links to other agencies' river information.

The District and numerous state and local partners are implementing projects that will reduce nutrient loading and improve water quality in the lower St. Johns River, from Lake George north to Mayport.

District projects include removing gizzard shad from Lake George, located in Volusia and Putnam counties, which is helping to reduce nitrogen and phosphorus in the lake and the river. The District also is working with local governments and water utilities to upgrade wastewater treatment plants and provide reclaimed water for irrigation at golf courses and other facilities. Using reclaimed water for nonpotable uses reduces potable groundwater withdrawals and reduces discharges of treated wastewater into the river and other natural water bodies.

In the Tri-County Agricultural Area, which includes Putnam, St. Johns and Flagler counties, the District works with the Florida Department of Agriculture and Consumer Services and area growers on regional water management projects and practices that reduce the movement of nutrients to the river, improve water conservation, and result in more efficient farm management while maintaining the long-term viability of agriculture.

Year-round, District scientists routinely collect water quality data at established sampling sites in the lower St. Johns River.

When conditions are right for algal blooms, typically from mid-May to early October, District staff collect algae samples for laboratory analysis to determine the algal species and possible presence of algal toxins. By using onsite measurements, observations and laboratory analyses, District scientists work to better understand the composition and status of algal blooms, and the source of nutrients that fuel blooms, in order to refine management strategies to reduce excess nutrients entering the river.

Not all algal blooms contain significant concentrations of algal toxins. Samples taken from the middle of the river in open water rarely show elevated levels of algal toxins. When algal toxins are detected, it is usually from samples taken in algal mats, or scums, isolated in small areas, often in coves, canals and creeks and along shorelines where algae have concentrated.

While algae are a natural component of the aquatic food chain, unusually dense algal blooms are a result of excess nutrients from fertilizer, wastewater and stormwater runoff. When these pollutants are combined with lots of sunlight, warm temperatures and a wide, shallow river, conditions become favorable for nuisance bloom development. In addition to the potential production of algal toxins, algal blooms can block sunlight from reaching aquatic plants, deplete dissolved oxygen in the river, and degrade the habitat for fish and other wildlife.

Lab results from the District's algae samples are shared with other agencies, including the Florida Department of Health (DOH), the Florida Department of Environmental Protection (DEP) and the Florida Fish and Wildlife Conservation Commission (FWC). Since 2009, these agencies have operated under a coordinated plan to respond to potentially harmful algal blooms.

For information about algal blooms from these agencies and other resources:

  • DOH Aquatic Toxins Program, or call (888) 232-8635 to report human illness from exposure to algal toxins
  • DOH list of Florida's county health departments
  • DEP frequently asked questions
  • FWC, or call (800) 636-0511 to report fish kills
  • World Health Organization (WHO)
  • The Fish and Wildlife Research Institute (part of FWC) technical report Resource Guide for Public Health Response to Harmful Algal Blooms in Florida
  • Lower St. Johns River Basin Technical Advisory Committee

    To learn more about what you can do to reduce the potential for algal blooms in the St. Johns River and other waterways, visit