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Florida's Algae Blooms Wreak Havoc

Naturally occurring algae has amped up 15-fold over half a century, fueled by excessive nutrients running into Lake Okeechobee. Here’s what’s happening and what’s being done.

Algae Bloom Behind Boat

Capt. Ed Semon of TowBoatUS Cape Coral tows a boat during one of the recent algae blooms in Florida, which is causing boating businesses to suffer. | Photo: Courtesy, Ed Semon 

Kyle Potts has seen his share of algae blooms in the Charlotte Harbor area of Florida's west coast, about 100 miles south of Tampa, but nothing like summer 2018. "The last four or five years have been worse than normal. But to me, last year was five times worse than anything I've seen in my 20 years here," says Potts. "It's killing my business."

Potts, the TowBoatUS tower for Charlotte Harbor, says last summer his business was down 50 percent as people avoided the water. The algae stinks, he says, and causes fish kills that smell even worse. "It began in July. One of our major boat ramps that normally has 100 vehicles parked in it on Labor Day weekend had maybe a dozen last year."

Normally, these temporary algae blooms last until winter. But this one became a monster that persisted. Here is the confluence of problems that combined to create it.

Problem 1

Red Tide

Only able to thrive in saltwater, red tide (Karenia brevis) is a large concentration of single-celled algae that occur naturally and tend to emerge annually between October and April, usually miles offshore in the Gulf of Mexico. According to Stephen Leatherman, a coastal environmental scientist from Florida International University, wind and currents sometimes bring the rust-colored algae near shore where it can get into estuaries and bays. Once the algae reach local beaches, growth is spurred by agricultural runoff, wastewater, and other diverse sources of nutrients. Normally, after a couple of months, it disappears.

Red tide itself isn't harmful to most people, Leatherman says. But when waves break and burst the algae cells, especially in unnaturally large blooms, brevetoxins are released into the air causing scratchy eyes and respiratory problems such as sore throat and cough, exacerbating asthma and COPD, and sometimes landing people in the hospital. Results of a 2006 study by the Centers for Disease Control and Prevention (CDC) and the Florida Department of Health showed that coastal residents had a 54 percent higher rate of respiratory diagnoses and hospital admissions during red-tide periods compared to when there was no red tide.

When shellfish consume the algae, brevetoxins concentrate. Countless fish and hundreds of marine birds, mammals, and sea turtles that ingested the toxins — either directly or from eating fish that ingested brevetoxins — were poisoned and died in 2018, including a 26-foot whale shark. On the picturesque beaches of Sanibel and Captiva Islands last summer, red tide caused thousands of fish and mammals to perish. Within two months, more than 115 manatees were trapped within the red tide and died. To protect fishermen, the Florida Fish and Wildlife Commission took the extraordinary step of temporarily changing rules for snook and redfish to catch-and-release in Gulf Coast counties from Manatee to Pasco.

Problem 2

Runoff Feeds Bacteria

In Florida, Leatherman says, there's also a proliferation of single-celled organisms called cyanobacteria, nicknamed "blue-green algae," a bacteria that grows in Lake Okeechobee's freshwater, some 35 miles inland. Completely different from red tide, cyanobacteria blooms are directly related to agricultural and urban runoff.

According to CDC and the University of Florida Sea Grant program, Lake Okeechobee pollution comes from phosphates and nitrates in farm fertilizers and where manure collects from animals, from septic-tank overflow and leakage, urban stormwater runoff, and household cleaners containing phosphorous. This nutrient-laden pollution feeds the bacteria, rapidly expanding the bloom. This flows into slow-moving rivers when the U.S. Army Corps of Engineers (USACE) is required to open flood-control waterways to maintain the integrity of the aging dike protecting people living downstream.

The South Florida Water Management District (SFWMD) works with USACE on the releases, and also to bring irrigation water to agriculture, and fresh water to the Seminole Indians south of the lake. As that polluted water makes its way to both coastlines, it picks up human-contributed nutrients along the way.

Blue-green algae can be dangerous to humans, says Larry Brand, marine ecology researcher at the University of Miami. "Cyanobacteria produces a suite of toxins. Research shows some cause long-term health problems, including liver disease and liver cancer." One of the worst toxins, BMMA, says Brand, can cause neurodegenerative disorders, including ALS, Parkinson's, and Alzheimer's. "BMAA is biomagnified in fish, where it accumulates," he says, and advises no swimming in water with cyanobacteria, and avoiding consuming seafood from waters with blooms.

Problem 3

Outdated Infrastructure

After a hurricane and massive flood killed thousands of Floridians in 1928, Lake Okeechobee was enclosed by a huge levee and dike to prevent that level of flooding and to control the release of water for agriculture downstream. To the south, this created a rich environment for industrial-size sugar cane fields and sugar-mill operations. The area is now the largest sugar-producing region in America.

Shallow Lake Okeechobee absorbs nutrients from surrounding land but can no longer filter them through the Everglades to the south as it could before the levee was constructed (see illustration below). During heavy rains, agricultural runoff from the north leeches into Lake Okeechobee. Thousands of acres of sugar cane farms south of the lake also flood, so SFWMD sometimes "back-pumps" much of this polluted floodwater up into the lake. An unintended consequence is that it feeds the natural algae, causing it to grow into thick mats that are released into the Caloosahatchee River and St. Lucie Canal.

Once the algae-laden water reaches the Gulf Coast and mixes with the red tide, it creates the toxic stew Floridians saw in 2018.

Florida CERP Map

CERP, the largest environmental restoration project in the world, aims to replumb the Everglades water system. | Photo: Courtesy, U.S. Army  Corps of Engineers, Jacksonville District 

The comprehensive Everglades restoration plan is now the largest environmental restoration project in the world.

Complicating Matters

The bottom of Lake Okeechobee has decades of agricultural sediments, possibly several feet thick, says University of Miami's Brand. "The lake is one of the largest in America but averages only about 8 feet deep. Wind blowing over that kind of fetch creates turbulence that mixes the sediments into the lake water."

Tropical storms exacerbate the situation. In 2017, as in 2005, massive storms flooded the sugar cane farms. Some of that runoff was back-pumped into the lake, forcing the dike to be opened and water released to take pressure off the aging dike system, resulting in larger- than-normal blooms. By July 2018, NOAA satellite imagery showed nearly 90 percent of the lake covered in cyanobacteria. Still, USACE was forced to release lake water to prepare for summer rains and potential hurricanes, which otherwise could have overwhelmed the old levee and dike.

For red tide and cyanobacteria, warming water temperatures also influence the size and duration of the blooms. Leatherman explains that when the lake level is lowered for flood control, the water gets warmer, worsening the problem. Brand adds that when red tide meets cyanobacteria that dies as it flows into seawater, red tide feeds on the decaying bloom and grows even faster.

Impact On Local Economies

There are nearly a million registered boats in Florida. According to the Florida Fish and Wildlife Conservation Commission, about 135 miles of Florida's west coast from Pinellas to Lee counties were affected in 2018. Parts of the northwest coast of Florida and other locations in the state were also affected.

Chris Wittman, a fourth-generation fisherman from south Florida, says last year there were still places with clear water to catch healthy fish in the area, but the fish were stressed because there were so few places to which they could escape. While eating uncontaminated fish isn't dangerous, Wittman says, last summer far fewer fishermen were willing to head out through slime to catch them, so chartering businesses and fishing guides were dramatically impacted. The Florida Department of Economic Opportunity reports that more than 80 businesses in Lee County alone lost an estimated $7 million over the summer.

"My business evaporated last year," says BoatUS Member Rich Russell, who owns a boat-maintenance and charter business on Pine Island in Bokeelia, Florida. "We didn't charter a single boat last season." Russell says the blooms also made it hard to work around boats in the water. "We repair boats and lifts. It was almost impossible to breathe. It smelled atrocious. I coughed for weeks. Usually by the time you get out of Captiva Pass, the water turns a beautiful emerald blue. Not last year. There were dead fish everywhere."

Dead Fish from Algae Bloom by Boat Lift

Chattonella subsalsa blooms like this one in Merritt Island, Florida, are often associated with fish kills. Accumulation of toxins from this type of bloom in shellfish can pose health risks for people who consume them.  | Photo: Courtesy, Florida Fish & Wildlife Conservation Commission

Red tide affected other areas of the U.S. as well, and according to the National Oceanic and Atmospheric Administration, it creates an estimated $82 million economic loss per year to American seafood, restaurant, and tourism industries. A Sarasota, Florida, county survey found that 90 percent of area businesses that responded reported losing business because of red tide; 46 percent reported business down by 50 percent or more compared to the same time the year before. Numerous other marine businesses also were affected. Louis Chemi, chief operating officer of Freedom Boat Clubs, saw a dramatic drop in the number of rental boats going out of the company's southwest Florida locations in July and August.

Where Do We Go From Here?

In 2018, Florida's then-governor, Rick Scott, declared a state of emergency for the cyanobacteria, then another for counties impacted by red tide. The Florida Department of Environmental Protection set aside $6 million for the 12 impacted counties, offsetting a few economic losses in the short run. To decrease septic-tank issues in the area, Scott announced a plan to connect residents around the lake and waterways to sewer systems and pay up to 50 percent of the cost.

Newly elected Florida governor Ron DeSantis has offered a more aggressive plan, recently ordering accelerated construction of a 17,000-acre reservoir in the Everglades south of Lake Okeechobee. The Comprehensive Everglades Restoration Plan (CERP) also calls for reservoirs to be built, and a University of Florida Water Institute report said that up to 1.6 million acre-feet of reservoir storage is needed. The reservoirs will eventually link up with a network of man-made filter marshes, called stormwater treatment areas, that remove harmful nutrients. The cleaned water can then continue its path through the Everglades to Florida Bay. CERP requires the conversion of state land to an open and more natural water flow to make this possible (see CERP illustration above).

The Constellation Of Solutions

South Florida's population grew by more than a half million from 2010 to 2015, making it the country's eighth most populous metropolitan area, with no signs of slowing down. According to the South Florida Water Management District's (SFWMD) 2011 Lake Okeechobee Protection Plan, about 12 percent of the total nutrient pollution in the lake comes from residences.

In 2000, Congress authorized the Comprehensive Everglades Restoration Plan (CERP), which has ballooned into a 50-year, $13.5 billion blueprint focused on increasing the storage and treatment of water in south Florida. One of the largest expenditures is for buying land needed for CERP projects. According to the U.S. Army Corps of Engineers (USACE), CERP is the largest environmental restoration program in the world, reflecting the enormity of replumbing the entire Everglades water system.

There are dozens of projects in the plan, many requiring years to complete and relying on completion of other projects. The federal government is required to pay half the costs of CERP, while state, local, and tribal agencies must pick up the remainder. According to South Florida Water Management District (SFWMD), the federal government has spent only $1.1 billion on projects, while the state so far has invested about $2 billion. Even after construction projects are complete, the ecological benefits won't occur immediately. But slow progress is being made through a network of federal and state agencies:

U.S. Army Corps Of Engineers:

Lead federal agency responsible for planning, designing, and constructing multiple components of CERP. Involved in dozens of projects, such as the Lake Okeechobee Watershed Restoration Project to improve the quantity/ timing of lake discharges.

U.S. Department Of The Interior:

Allots funding to the National Park Service, Fish and Wildlife Service, U.S. Geological Survey, and Bureau of Indian Affairs. Protects the diverse fish and wildlife resources of south Florida. Plans and predicts effects of aquifer storage and recovery.

South Florida Water Management District:

Partners with USACE and coordinates studies and projects on the state level. Monitors and models changes in Everglades vegetation to check effects of water-management practices on plant communities. Involved in acquiring the massive amounts of land needed for CERP. To date, more than 60 percent of the land initially identified as necessary has been purchased.

Florida Department Of Environmental Protection:

Focuses on improving water quality, restoring hydrology and ecology of Everglades ecosystem, and provides guidance and assistance to USACE. The department has developed a Basin Management Action Plan identifying pollutant sources and restoration projects.

Florida Fish And Wildlife Conservation Commission:

Provides science-based guidance for establishing/managing Everglades water levels.

– C.F.

On The Federal Level

Our BoatUS Government Affairs manager David Kennedy adds: "There's support on both sides of the political aisle to continue funding CERP as part of the Water Resources Development Act (WRDA). Currently, this is the primary federal vehicle for restoring the Everglades and reducing the impact of harmful algae blooms. The bill authorizes investment in waterways and promotes policies to address water-quality concerns such as Florida's harmful algal blooms."

In a January 18, 2018, letter to President Donald Trump, Rep. Brian Mast (FL-R) wrote: "These Congressionally authorized projects create a roadmap to ensure the survival of Florida's ecosystem. … Without restoration, Floridians from across the state will continue to combat life-threatening events through rising waters, devastating storms, and ecological destruction."

Ultimately, the administration did not include this funding in its 2019 budget. Congress did, however, approve funding for CERP as part of its FY2019 spending legislation.

"BoatUS continues to work to secure funding for CERP and other ecosystem restoration projects through the regular appropriations process," says Kennedy. "We've also been working with Rep. Mast on legislation known as the ‘Harmful Algal Bloom and Hypoxia Research and Control Act' (HABHRCA), legislation to support interagency actions to combat harmful algae blooms. BoatUS also worked to secure additional dredging and levee-repair funds as part of last year's disaster- relief legislation, which freed up resources that can now be used support CERP." (See "The constellation of solutions" in the section above for details on CERP.)

As an emergency stopgap measure, the USACE Lake Okeechobee Regulation Schedule protocols, which determine when and how much water is let out of the lake, will be studied to determine if more water can be safely held in the lake. That could mean less water flushed down both rivers — a temporary improvement.

Other solutions call for spraying the lake with herbicide to kill the cyanobacteria, but experts believe this would worsen the problem. "Decaying bacteria will create even more nutrients for the next round of blooms," says Brand. "Seventy years ago, Lake Okeechobee had clear water and a sandy bottom. The problem won't go away until the nutrient pollution from agriculture and household waste stop filling the lake."

Dead Fish from Algae Bloom by a Grassy Shore

A prymnesium parvum bloom kills fish in a lake near Jacksonville, Florida. | Photo: Courtesy, Florida Fish & Wildlife Conservation Commission

Since 2000, 68 different projects were started to help return the natural timing and delivery of water through the Everglades ecosystem. To date, few, if any, have been completed. According to a National Academies of Sciences, Engineering, and Medicine report by Fernando Miralles-Wilhelm, Florida International University, published in 2011 in the journal Ecohydrology, only 20 percent of the projects so far have been funded or are in progress. At the same time, there's been less monitoring by the state due to defunding. According to Florida International University's Southeast Environmental Research Center, since 2007, the number of water-quality sampling stations was reduced from about 350 down to only 115.

What About 2019?

Predicting red tides and blue-green algae blooms more than a few days in advance is tricky; no one yet knows if this year's weather will cause another superbloom. Red tide will almost certainly reappear this fall, but no one can say if it will equal 2018's massive blooms. Given that red tide was still lurking along the Florida west coast late last winter, a season when normally it would have receded into the Gulf, there's a possibility that 2019 could also bring such water-quality threats. The blue-green algae will likely bloom again, but it's unknown to what extent.

Red tide in the Gulf of Mexico

High concentrations of Karenis brevis found in the waters of the Gulf of Mexico produces "red tide."

"Change is happening," Kennedy said, "and while the pace has been slow in the past, we're encouraged by the unanimity of the Florida legislative and executive branches' preliminary budget allocations for Everglades restoration. It's unprecedented to see all three branches start at essentially the same funding level, which is what has happened in the 2019 Florida legislative session."

As we go to press, the Florida legislature and new governor have proposed nearly identical funding levels of more than $600 million for the Everglades and other clean-water projects, twice what we've seen in past years. "Seldom do we see the House, Senate, and governor start at the nearly same level of funding for projects," added Kennedy.

The budget won't be final until May 5, but there appears to be reason for more confidence that at least $600 million will be headed toward clean water projects in Florida, according to Kennedy. "It's good news that Floridians with normally disparate interests — business and home owners, the hospitality industry, environmental advocates, Democrats, Republicans — are finally uniting around their shared interests, and a shared understanding of the real roots of this problem."

For More Information On Florida Beach Conditions:

BoatUS, the voice of recreational boaters on Capitol Hill, is the only national boat-owner organization with a full-time Government Affairs staff. Visit Advocacy.BoatUS.com to stay informed on relevant federal and state boating issues, and sign up to receive Action Alerts emails so you can take action when important legislative issues affecting boaters arise.

Charles Fort

Charles handles our exclusive Reports in-depth tech feature in every issue, our videos, and our investigative features. He helps with dispute-mediation and writes our Consumer Protection column. A member of the National Association of Marine Surveyors, he’s on ABYC tech committees, and has a 100-ton U.S. Coast Guard license. A sailor who went cruising with his family, he now lives in California.