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Florida algae bloom leaves a rotting, rancid slime

The algae bloom on the St. Lucie River clogged engine intakes on boats.

The toxic cyanobacteria bloom began as slime green, turned bright blue, then brown and finally transmuted into a mass of black rot as the stench hanging over the St. Lucie River ripened from the smell of rotting garbage to putrid carcasses to feces.

It took five weeks for the algae bloom to run its course at Central Marine in Stuart, Florida, and during much of that time business was at a near standstill, says manager Mary Radabaugh. Carried by wind and tide from the river into her marina basin, the algae piled up in a mat 4 to 8 inches thick from seawall to seawall. The soggy mess clogged engine intakes on boats, and its smell gave employees headaches, irritated their eyes and throats, and caused some to vomit.

“The mat was so thick we couldn’t get the Travelift strap into the water,” Radabaugh says. “We couldn’t haul boats for a couple of days. As far as business, nobody came. There were signs all over: Don’t touch the water. Don’t get near the water.”

The noxious bloom was the worst in memory on the St. Lucie, though certainly not the first. It ruined much of July for marinas, boatyards, paddleboard and kayak concessions, fishermen and charter boats. It closed beaches and drove riverfront homeowners to escape the stench by staying at hotels or going on vacation.

Algae blooms on the St. Lucie River and the brackish estuary it feeds into, the Indian River Lagoon, “have been going on for 20 to 30 years,” says Phil Norman, a partner in Outboards Only, an outboard repair yard and neighbor of Central Marine.

It has some folks thinking about relocating. Norman says two of his customers plan to sell their houses on the St. Lucie and move to Cedar Key on Florida’s northwest coast, “where they don’t have to deal with this.” But there are no guarantees that blooms won’t affect them there.

Sporadic outbreaks of red tide — blooms of the Karenia brevis organism, which is even more toxic than blue-green algae — have caused fish kills and shut down clamming off Cedar Key in the Gulf of Mexico, most recently in 2014.

But the blue-green algae blooms on Lake Okeechobee and the St. Lucie River, which flows from the lake to the Indian River Lagoon on Florida’s east coast, and on the Caloosahatchee River, which runs from the lake to Pine Island Sound on the west coast, occur with maddening regularity. The blooms develop when the Army Corps of Engineers releases billions of gallons of nitrogen- and phosphorus-laden fresh water into the rivers to draw down lake levels and reduce pressure on Okeechobee’s old and weak 143-mile earthen levee.

“Long-term, this is going to happen pretty much every year,” says Capt. Rufus Wakeman, a fishing guide and owner of River Palm Cottages and Fish Camp on Indian River Lagoon. “When the lake gets to 14 or 15 feet you’ve got to start lowering it, period. If you’re going into hurricane season, you can’t have that water too high.”

The Corps of Engineers has been reinforcing the levee, but it needs a lot more work. During a 1928 hurricane the lake’s waters topped the levee and flooded nearby communities and agricultural land, leaving almost 2,000 people dead.

The mess left by the blooms shut down boating in some areas of Florida.

A “perfect storm” of unusually heavy El Niño-related rainfall last winter, big storm-water runoffs into the lake carrying nutrients from sugar fields, dairy farms and residential developments, and warming water generated a blue-green algae bloom that grew to 200 square miles on Okeechobee and migrated into nearby rivers.

“One-hundred-fifty billion gallons of polluted water [went] east into the saltwater estuarine system between January and July,” Wakeman says. “Double that has gone west. Those are staggering numbers.”

The result: seagrass die-offs in brackish estuaries diluted with too much fresh water and in waters where miles of matted algae and algal-induced turbidity blocked sunlight; fish kills from oxygen deprivation when algae cells die and bacteria eat them, sucking oxygen from the water; and loss of shellfish in salt water that’s no longer salty enough.

Florida Gov. Rick Scott declared a state of emergency in Martin, St. Lucie and Palm Beach counties on the east coast and Lee County on the west in response to the blooms.

“[This year’s] freshwater discharges destroyed an alarming amount of seagrass beds and oyster bars in the lower Caloosahatchee estuary,” says Capt. Daniel Andrews, a Florida west coast fishing guide and founder of Captains for Clean Water. “These grass beds are the foundation of the fishery. They cannot withstand prolonged exposure to fresh water. Also, the turbidity of the water prevents the grass from photosynthesizing.”

Andrews has seen and foresees a continuing decline of the estuary and its resources if nothing is done. “The damage caused by the freshwater discharges take years, even decades, to recover from,” he says. “Generally, before the area recovers from a discharge episode, we experience more discharges. It’s a vicious cycle.”

And it’s one that doesn’t bode well for marine life. Ernst B. Peebles, a biological oceanographer who studies the effect of blooms on fish, says his findings are clear: Blooms are bad for sport fishing. “The more often you have these algae blooms, the fewer gamefish you have,” Peebles says. “If it gets bad enough, you won’t have any.”

Though poisoning from red tide toxins often is the cause of the most dramatic fish kills, where beaches are covered with fish carcasses, most bloom-related kills are attributable to the depletion of oxygen in the water, he says.

Peebles notes, too, in a July 2016 blog, that the number of algal blooms has been growing “at an exponential rate,” not just in Florida but also around the world. “As the world’s population grows and it becomes more industrialized and urbanized, and more land is used for agriculture and raising livestock, we have more nutrients — more fertilizers and sewage” — in storm-water runoff and untreated wastewater that ends up in rivers, lakes and seas. This provides the nutrient-rich soup that feeds blooms.

Climate change — NOAA reports that 2014 and 2015 were the hottest years on record — is likely to promote more blooms since algae proliferates in warm water. And this will trigger more fish kills since warmer water holds less dissolved oxygen, Peebles says.

Blooms keep making headlines around the country and the world:

• They have been reported this summer in lakes and rivers in North Dakota, Minnesota, Utah, Southern California and Ohio, which has been sizzlingly hot.

• In August 2014, Toledo, Ohio, issued a do-not-drink advisory to almost a half-million residents after finding elevated levels of microcystin, a blue-green algae toxin, in the drinking water because of a bloom in Lake Erie that is almost an annual event now. A month later, the algae covered 636 miles of the Ohio River.

• In the spring and summer of 2015, a coastal bloom from central California to British Columbia released dangerous levels of the toxin domoic acid, shutting down recreational and commercial shellfishing in Washington, Oregon and California and temporarily closing the Dungeness crab fishery off Washington.

• Also in the summer of 2015, a bloom covering 7,500 square miles washed ashore on the resort beaches of Qingdao, China, prompting the mobilization of hundreds of boats and bulldozers to remove it. The bloom returned this summer.

• Chile declared a state of emergency in the Chiloé Archipelago after an enormous red tide bloom killed 40,000 tons of salmon, millions of sardines and numerous whales.

Peebles says that, in general, the nutrient overload in lakes and rivers that promotes blooms can be alleviated by wastewater treatment, the use of retention ponds to capture storm-water runoff and hold it while nutrients settle to the bottom to be absorbed by vegetation, and better water management to slow water flow so it seeps sideways through the soil to its destination rather than rushing down streams, rivers and canals.

The blooms form when nutrient-laden water from Lake Okeechobee and storm runoff make their way into brackish estuaries.

Yet the long-term answer for stemming the flow of fresh water and nutrients into the St. Lucie and Caloosahatchee estuaries is the $16 billion Comprehensive Everglades Restoration Plan, says Stephen Davis, an ecologist for the Everglades Foundation. “The Comprehensive Everglades Restoration Plan of 2000 is a collection of projects,” Davis says. “No single project will solve the problem, but if we do it all, we can ratchet down on the discharges.” This should offer relief from the blooms.

The plan is supposed to:

• restore the flow of water from the north part of the state to Florida Bay through the Everglades

• reduce the reliance on man-made canals and on the St. Lucie and Caloosahatchee rivers to carry water to the coasts

• reduce the amount of water impounded in Lake Okeechobee

• filter out the bloom-causing nutrients in shallow impoundments north and south of the lake and increase the flow of fresh water to Florida Bay, which has been dying because of “hypersalinity”

This “fix” has been poking along for 16 years, mostly for lack of funds and political will to make it a high priority at the state and federal levels. Wakeman and others have called on citizens — politicians, especially — to sign a “Now or Neverglades Declaration” to hasten the purchase of 100,000 acres of sugarcane fields south of the lake to create marshes to store fresh water from Okeechobee, filter out the nutrients and send the water south to Florida Bay. The purchase could accelerate the schedule for diverting lake water south and finally offer some relief to the coastal estuaries.

Florida has the money to buy the acreage, Wakeman says. In 2014 three of four Florida voters cast ballots in favor of an amendment raising about $740 million a year from real estate stamp taxes to buy, acquire and protect wildlife habitat, water resources and parkland. So far, the state hasn’t spent any of that money on conservation lands.

The blooms have been disastrous, Wakeman says. U.S. Sugar, which had offered to sell the agricultural lands to the state in 2008, has withdrawn its offer. Wakeman challenges the company to be part of the solution now. “Be a hero, not a zero,” he says.

This article originally appeared in the October 2016 issue.