Monitoring of Blue-Green Algae Increased In South Florida

The South Florida Water Management District announced on Aug. 18 it has launched an extensive monitoring program to track and report on the existence of blue-green algae throughout district water bodies.

A naturally occurring phenomenon that exists worldwide, blue-green algae multiply quickly in water with high nutrient levels, particularly when the water is warm and the weather is calm. This proliferation causes "blooms" of floating blue-green algae that turn the water green. Florida -- along with Michigan, Oregon and Virginia -- are currently experiencing massive algal blooms.

The district's monitoring program comprises 41 sampling sites, including Lake Okeechobee; the St. Lucie River and estuary; the Caloosahatchee River and estuary; the Kissimmee Chain of Lakes; Lake Istokpoga; and District canals. The monitoring program will be conducted for as long as necessary at an approximate cost of $300,000 and will be coordinated with other state and county agency monitoring efforts.

"We've significantly expanded both our monitoring locations and frequencies," said Dean Powell, SFWMD director of Watershed Management. "This action will standardize the way samples are collected and processed in order to ensure accurate date are reported on algal conditions in our coastal estuaries and other bodies of water throughout the region."

In addition to the stepped-up monitoring, the district is working closely on the blue-green algae issue with local, county, state and federal agencies including the Florida Department of Environmental Protection, Florida Fish and Wildlife Conservation Commission, Florida Department of Health, St. Johns River Water Management District, University of Florida, county governments and local utilities.

FAQ ON BLUE-GREEN ALGAE (from SFWMD)

What are blue-green algae?

Blue-green algae are natural to the environment and are found all over the world. They are not unique to South Florida Water Management District water bodies. They are also common throughout the state as well as in other states, including Georgia, Texas, Alabama, Maryland, Virginia, Michigan, Oregon and others.

What causes blue-green algae blooms?

Blue-green algae multiply quickly in water bodies with high nutrient levels such as phosphorus, particularly when the water is warm and the weather is calm. This proliferation causes "blooms" of floating blue-green algae that turn the water green. These three ingredients -- warm water, calm weather and high levels of nutrients -- are presently fueling the blooms in the area.

Where are the blue-green algae blooms today?

The South Florida Water Management District is experiencing blooms in Lake Okeechobee, St. Lucie River, Caloosahatchee River, C-51 Canal in Palm Beach County and a light bloom in the Upper Kissimmee Chain of Lakes.

Blooms are occurring in other Florida water bodies outside of the South Florida Water Management District region, such as the St. Johns River near Jacksonville. Blue-green algae blooms were also recently reported in Michigan (Lake Huron) and Oregon (Odell Lake).

Are blue-green algae toxic and a health risk to humans?

It is important to understand that some -- not all -- species of blue-green algae can produce toxins that can affect public health. Those blue-green algae that are known to produce toxins, do not always do so. Little is known about the environmental conditions that trigger toxin production.

The blooms in South Florida Water Management District waterways are caused by blue-green algae called Mycrocystis. This blue-green algae are not always toxic but can form toxic strains. The toxin -- called microcystin -- can be a threat to fish, pets, livestock, wild animals and humans if ingested or inhaled. However, information regarding toxins from blue-green algae and risks to humans, fish and wildlife is very limited.

Currently, there are no established state or federal guidelines for standard toxic levels of concern. The World Health Organization suggests 1.0 microgram per liter for drinking water.

The South Florida Water Management District is working closely with the state Health Department medical experts, who will provide information regarding known human health risks associated with varying levels of toxic blue-green algae. Health Department officials recommend staying out of the water where algae blooms are concentrated as a precaution.

What is the South Florida Water Management District doing about the blue-green algae blooms?

The South Florida Water Management District is coordinating monitoring, evaluation and communication efforts with local, county, state and federal agencies including the Florida Department of Environmental Protection, Florida Fish and Wildlife Conservation Commission/Florida Fish and Wildlife Research Institute, Florida Department of Health, St. Johns River Water Management District, Southwest Florida Water Management District, University of Florida, county governments and local utilities.

The district has increased blue-green algae toxin monitoring locations and frequency throughout central and southern Florida. Beginning Aug. 22, samples will be collected at 41 stations every two weeks from May to October, and every month from November to April. The tests will be conducted in the Caloosahatchee and St. Lucie estuaries, Lake Okeechobee, the Kissimmee River and upper chain of lakes as well as many canals throughout the district.

The district is looking to use the help of a nationally renowned blue-green algae expert to serve as a consultant.

Are there toxic blue-green algae in Lake Okeechobee and the coastal estuaries?

Elevated toxin levels ranging from 20 micrograms per liter to 373 micrograms per liter were found this month in samples collected from Lake Okeechobee, St. Lucie River and C-51 Canal and analyzed by the Florida Fish and Wildlife Research Institute. Results from recent testing in the Caloosahatchee are expected in late August.

Can large blue-green algae blooms cause fish kills?

Blooms of blue-green algae that last more than a few months can be harmful to lake/river ecosystems and cause fish kills because of the decrease in oxygen levels and direct ingestion in the food chain.

How long will the blooms last?

Blooms can last days, weeks or months, depending on conditions. Scientists cannot predict when or where blooms will occur or how long they will last; the blooms will run their course and dissipate naturally.

Can blue-green algae blooms be treated?

No. The Florida Fish and Wildlife Conservation Commission does not recommend treatment because it may release the toxins.

The South Florida Water Management District: http://www.sfwmd.gov

This article originally appeared in the 08/01/2005 issue of Environmental Protection.

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