To save Everglades, guardians fight time - and climate

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To save Everglades, guardians fight time - and climate

Nearly two decades and $4 billion into a sweeping restoration program, new data about the pace of climate change has raised questions about how much of Everglades National Park can ever be regained

Tiffany Troxler Florida International University researcher says.

"To a layman, this patch of brown-green saw grass and button mangrove deep inside Everglades National Park looks healthy enough, but Troxler knows trouble lurks just beneath the murky surface. She points to a clump of grass: Beneath the water line, the soil has retreated about a foot, leaving the root mass exposed. It is evidence that the thick mat of peat supporting this ecosystem is collapsing — and research suggests encroaching sea water is to blame.

"ou can think about these soils as your bank account,” says Troxler, associate director of FIU’s Sea Level Solutions Center. "In the condition that this marsh is right now, the outlook is not good."

Formed roughly 5,000 years ago, during a time of sea level rise, the Everglades once comprised an area twice the size of New Jersey.

"The miracle of the light pours over the green and brown expanse of saw grass and of water, shining and slow-moving below, the grass and water that is the meaning and the central fact of the Everglades of Florida,” journalist and activist Marjory Stoneman Douglas famously wrote in 1947. “It is a river of grass."

But over the course of just the last century, about half of the Everglades’ original footprint has been lost — plowed under or paved over, never to be recovered, so long as South Florida’s 8 million human inhabitants claim it for their homes, livelihoods and recreation.

The glades have been sapped by canals and dams that remapped the landscape and altered animal habitats, polluted by upstream agricultural areas, transformed by invasive species. And now, rising sea levels — this time, caused by man — threaten to undo what it took nature millennia to build.

What survives is not so much a natural ecosystem, but a remnant, heavily dependent on — and at the mercy of — a network of more than 2,100 miles of canals, 2,000 miles of levees and hundreds of floodgates, pump stations and other water-control structures.

What the Army Corps of Engineers calls a “highly managed system,” others have sardonically labeled a “Disney Everglades.”

Nearly two decades and $4 billion into the Comprehensive Everglades Restoration Plan, an ambitious federal-state program adopted in 2000, new data about the pace of climate change have called into question how much of the Everglades can ever be salvaged — and what that even means.

“I tend to think that everything can be saved,” says Fred Sklar of the South Florida Water Management District, which monitors and runs much of the Everglades’ infrastructure. “Restored is another question.”

Today, we understand that natural systems like the untouched Everglades provide enormous benefits — water filtration, nurseries for fish and other wildlife, protection from storm surges, even carbon sequestration. But to 19th-century Floridians, all that water — and the mosquitoes and reptiles it harbored — represented an impediment to progress.

And so when Florida became a state in 1845, one of the Legislature’s first acts was to pass a resolution asking Congress to survey the “wholly valueless” Everglades “with a view to their reclamation."

Beginning in earnest during the 1880s, a host of entities set about draining the swamp. They dug canals east and west from Lake Okeechobee, carrying nutrient-laden water that altered the salinity of coastal estuaries and caused toxic algae blooms. They seeded the wetlands from the air with a thirsty, paper-barked Australian tree called melaleuca. The vast custard apple forest that girded the lake’s southern shore was torched, burning so fiercely that it set the very earth on fire.

Peat soils that had accumulated over thousands of years dried up and blew away. The result: At the University of Florida Research Station in Belle Glade, a concrete marker driven through the organic soil down to the limestone substrate shows the ground has sunk 6 feet since 1924.

And still, the tinkering went on.

In the 1960s, the Corps began straightening the meandering, flood-prone Kissimmee River. Lined by wetlands so lush that they were known as “the Little Everglades,” the shallow, 130-mile river was what one wildlife expert called a “nursery ground for sport fishes.” By 1971, engineers had straightened the once free-flowing stream into a 56-mile, 30-foot-deep canal bureaucratically designated as the C-38.

But it was an event in 1928 that, as much as any, altered the Everglades’ course. That year, a hurricane overwhelmed the flimsy dike along Lake Okeechobee’s southern shore, causing a deluge that killed 3,000 people, most of them poor, black farmworkers. The resulting 143-mile, 30-foot-high Herbert Hoover Dike now nearly completely surrounds the lake, permanently severing its connection to the park.

The Corps’ primary mandate was to protect people, not the environment. As the narrator put it in the 1950s documentary “Waters of Destiny,” the agency saw itself as victorious in a war against nature:

“Water that once ran wild. Water that ruined the rich terrain. Water that took lives and land. Put disaster in the headlines and death upon the soil. Now, it just waits there. Calm, peaceful. Ready to do the bidding of man and his machines.”

Scientists estimate that more than 650 billion gallons of fresh water a year once flowed south into what is now Everglades National Park. Today, that flow is about 280 billion gallons.

Flash forward to the present day, when many of the same canals and levees and pumps that helped drain the Everglades are now being used to try to save them. Alongside the Everglades Agricultural Area, the 700,000-acre checkerboard of sugar cane and winter vegetable fields south of Lake Okeechobee, huge tracts are being converted to store and clean water for use when and where it is needed.

Perhaps the biggest step toward that end so far is the re-engineering of Tamiami Trail, the east-west highway that essentially has acted as a dike through the heart of the Everglades since the 1920s. Since 2013, workers have elevated 3.3 miles of the roadway, allowing water to flow freely into Shark River Slough, historically the deepest and wettest part of the Everglades.

“We're starting to see the vegetation respond, and we're getting more of those marsh grasses, more of those open water sloughs,” says Stephen Davis, senior ecologist with the Everglades Foundation. “I'm very confident that we can restore this ecosystem. And by restoration, I mean enhancing the functionality of what remains.”

“We’re on the threshold of seeing whether the previous 20 years of work will pay off," says William Nuttle, a consultant with the University of Maryland's Center for Environmental Science who began his career in the marshlands of South Florida.

But time is not on the Everglades’ side.

Over the past decade, scientists began noticing an alarming trend in the wetlands near the park’s southwest tip — “potholes” of open water filled with dead vegetation. Sea water, Nuttle says, was causing vast areas of once-healthy saw grass prairie “to unravel like a moth-eaten wool sweater.”

A lack of fresh water from the north and the intrusion of sea water have boosted salinity levels in the marshes, Troxler and others say, which appears to be hindering plant growth.

Scientists are counting on mangroves and other more salt-tolerant plants to migrate inland into the saw grass plains, establishing a new, natural bulwark against climate change. But that change may already be outpacing nature’s — and man’s — ability to counter it: When the restoration plan was adopted in 2000, its authors were anticipating seas to rise only 6 inches by 2050. They’ve since already risen 5 inches.

In its most recent report to Congress, a panel of the National Academies of Sciences, Engineering, and Medicine urged a sweeping reassessment of restoration projects, warning that the current work is lagging behind the pace of climate change and could take 65 years to complete at the current funding levels.

"At this pace of restoration, it is even more imperative that agencies anticipate and design for the Everglades of the future,” they wrote.

SOURCE ARTICLE ABOUT THE EVERGLADES ON ABC NEWS

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