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Algae Blooms on Florida Beaches

Florida Governor Rick Scott was forced to declare a state of emergency in late June to help stop the spread of blue-green algae in South Florida waterways. Three counties in the state’s Atlantic coast were already forced to close the beaches before the busy July 4th weekend. The sludge was as thick as guacamole, and is highly toxic to marine animals. It can cause minor irritations such as rashes, respiratory issues and vomiting in humans. Residential areas near waterways have been inundated by the stench of the algal bloom, which is comparable to the smell of sewage and dead fish. The media has rushed to South Florida to discover both the cause and solution to this algae bloom, but the seemingly sudden outbreak has been a long time coming.

What is happening in the water?

Blooms of blue-green algae, or cyanobacteria, are commonly associated with excessively high amounts of nutrients in a water system, and can be additionally catalyzed by warm stagnant waters. While these organisms are natural and important to aquatic ecosystems in small amounts, major blooms cause cyanobacteria to block out other forms of life within a waterway. Cyanobacteria release toxins, known as cyanotoxins, which produce major fish kills and can have adverse effects on humans as well. While immediate symptoms in humans are usually only mild irritations, the neurotoxins released by the algae have been linked to neurodegenerative diseases such as Alzheimers and Parkinsons (Li 2012).

Harmful algal blooms are far from a recent phenomenon. The iconic 1963 Hitchcock film “The Birds” was based on the concept of cyanoneurotoxins altering the behaviors of coastal animals. Red tides, as well as the blue-green variety currently in Florida occur periodically along most populated coasts. The cause for all of these algal blooms is eutrophication – an excess amount of nutrients in the water, often caused by runoff from the land.

Eutrophication disrupts the delicate balance of the elements iron, phosphorous, and nitrogen in which aquatic ecosystems exist. The amounts of these three elements limit each other’s reactions, preventing a huge outburst of plant life that we see in algal blooms. Fertilizer contains high amounts of nitrogen and phosphorous, and when fertilizer mixes with rainwater, runoff enters the water system. This leads to increased amount of phosphorus and nitrogen in the water, and creates an environment of unlimited plant growth. This plant growth is so thick and toxic that it wipes out all animal life in the region.

Why is this happening in Florida?

Florida used to mostly be a wilderness swamp, but in the early twentieth century, Henry Flagler and other developers planned to drain the Everglades. After hurricanes in 1926 and 1928 that resulted in extensive flood damage to the new developments, the Army Corps of Engineers built a dike south of Lake Okeechobee. Naturally, Lake Okeechobee flowed south through over a hundred miles of sawgrass wetlands, but after the dike and later expansion projects, the water flow was cut off. As the Everglades ran dry, excess water from Lake Okeehobee would now be pumped through a system of canals and the St. Lucie and Caloosahatchee Rivers.

Source: http://earthobservatory.nasa.gov

The environmental effect of this alteration was devastating for both the Everglades and the rivers, but it allowed for the development of farmlands south of the lake. Restoration projects to reestablish some of the Everglades’ original flow began in the 1980’s and still continue today, but the fact remains that much of the excess water from Lake Okeechobee is pumped eastward and westward through the drainage rivers in amounts determined by the Army Corps of Engineers.

Florida’s rainy season generally runs June through October, meaning the Corps will dump water out of Lake Okeechobee around June to ensure the lake does not breach the levy. The Corps attempts to keep the lake level between 12.5 and 15.5 feet. Criticism from coastal communities comes following these drainages, as the result along inlets is dirty water that results in massive fish kills. Lake drainage in February and March of this year resulted in a record breaking fish kill on Florida’s Atlantic coast, an unheeded warning of the contaminants in Lake Okeechobee’s water.

This summer’s algal bloom comes after the release of water from Lake Okeechobee at the start of the rainy season. Surrounding the lake are 640,000 acres of farmland, predominantly sugarcane, that pump fertilizer runoff directly into Lake Okeechobee. While the South Florida Water Management District was quick to applaud the sugar industry earlier this year for reducing phosphorous pollution amounts, the water supply remains much too dirty to be allowed to flow into the Everglades, so it is sent to the Atlantic and Gulf coasts.

What Can Be Done?

While the Army Corps of Engineers has claimed that it will reduce Lake Okeechobee’s drainage in the future, the agency’s primary priority is the protection of the 40,000 residents south of the lake. With an eroding levee and repair projects expected to last several years, the Corps expects to continue keeping lake levels low. The only permanent solution is to restore Lake Okeechobee’s natural flow southward, which would both clean up the coastal waterways and mitigate the Everglades’ water shortage.

In 2008, the former Governor of Florida, Charlie Crist, reached a deal with U.S. Sugar, where the state would buy 180,000 acres of land for $1.75 billion. The deal would create a drainage field for water from Lake Okeechobee to the Everglades, naturally draining out the pollutants before the water reached the Everglades and eliminated the region’s largest polluter.

After the economic downturn Crist lost support for his deal among legislators, and was forced to settle with buying only 26,800 acres for $194 million, with future options for buying more of the land. In 2011 Rick Scott became governor with a campaign backed heavily by the sugar industry. The South Florida Water Management District under the Scott Administration let a 2013 option expire that would have purchased 46,800 acres, and voted against acting on another option to buy 46,800 acres earlier this year.

Under Section 303 (d) of the Clean Water Act states must establish ‘Total Maximum Daily Loads’ (TMDLs) for every waterway. These TMDLs represent the most pollution that can be in a waterway for the waterway to be considered safe. For Lake Okeechobee and surrounding waterways the phosphorous TMDL is a five year rolling average equal to 1680 metric tons of input per year. It is estimated that over 4000 metric tons of phosphorous enter the lake annually, with 70% coming from agricultural sources. The movement of this contaminated water into other ecosystems, such as the St. Lucie River which is the peak of this year’s algae bloom, also violates the TMDLs for that waterway.

These algal blooms are temporary, and the current one disrupting beach-going Floridians will dissipate soon, but the only way to prevent future blooms and yearly fish kills is to stop pumping polluted Lake Okeechobee freshwater into clean saltwater ecosystems along Florida’s coast.

Edited by: Summer Lee and Shreya Singireddy