Editor’s note: This is the first of a three-part series on the importance of restoring the state’s barrier islands. The second part will appear in the Wed., Aug. 1 edition. The final segment will appear in the Sun., Aug. 5 edition.
Ten miles from Louisiana's receding shore, on an island that was on the verge of sinking away, new land is growing at a rate of 200 feet per day.
A slurry of sand blasts from a 30-inch-wide pipe with the force of a firehose. In foaming sheets, it spreads across the beach of Whiskey Island, making it thicker and wider by the minute.
Backhoes and bulldozers finish the job, sculpting the sand into something resembling the island's younger self, before storms, oil spills and erosion took a heavy toll.
The project's manager, John Huit, suppresses a prideful grin as he watches a landscape quite literally taking shape before his eyes.
"Where we're standing was nothing but water - 12 feet deep - when we started this," he said, standing in rubber boots next to the gushing pipe.
The $118 million restoration of Whiskey Island on the edge of Terrebonne Bay is one of the world's biggest land building projects. More than 15.8 million cubic yards of sand - enough to fill the Superdome three times - has been dredged and spread across the island, creating nearly 2,000 acres of new beach and marsh. More sand was moved than the state's previous record, the Caminada Headland restoration, which spread 8.8 million cubic yards across 13 miles of coast, from Port Fourchon to Elmer's Island.
Whiskey Island's restoration, which is set to wrap up in early fall, amounts to only a fraction of the money and sand Louisiana is pouring into the rescue of its chain of barrier islands … and for good reason. Growing smaller and fewer in number by the year, the more than two dozen barrier islands are Louisiana's "first line of defense against hurricanes and storm surges," Gov. John Bel Edwards said.
The slim, sandy islands act as speed bumps, absorbing wind and wave power that would otherwise travel unimpeded through fragile wetlands and into towns and cities, including metro New Orleans.
Behind barrier islands, watery worlds meet and blend into something more complex. The sea, calmed by protected bays, mixes with river water rich in sediment and nutrients, giving rise to a third kind of ecosystem - one that teems with fish, shrimp and oysters. Suspended river sediment is slowed long enough to sink, eventually stacking into new land or building back what erosion had taken away.
Barrier islands themselves are much less dynamic, except during nesting season. The islands draw raucous crowds of gulls and terns every spring. Some bird species nest nowhere else, including the state's icon, the brown pelican. Seven barrier islands host 90 percent of the state's population of nesting pelicans.
Over the past 20 years, nearly $817 million has been spent restoring Louisiana's barrier islands, bulking up 75 miles of beach and back-island marsh, according to a recent assessment by the state Coastal Protection and Restoration Authority (CPRA).
The state plans to invest another $1.5 billion over the next 50 years as part of the Coastal Master Plan, an ambitious restoration and storm protection initiative estimated to cost $50 billion.
Despite the barrier islands' importance, and the vast sums of public money going into their repair and upkeep, they are out of sight, out of mind for most Louisianans. That's not the case in many coastal states, where barrier islands are prime real estate dominated by beach homes, hotels and crowded beaches. Louisiana's islands are remote, low-lying and often bare. Only Grand Isle, population: 1,400, has a year-round human presence.
"Not many people think about them, but the barrier islands are critical for our coast," said Windell Curole, manager of the South Lafourche Levee District. "Restoring them offers us a better chance of survival."
On a warm August night in 1856, a raging hurricane made a direct hit on Isle Derniere, a 24-mile-long barrier island that guarded Terrebonne Parish's soft, marshy middle. French for "last island," Isle Derniere boasted a sprawling resort popular with New Orleans' wealthiest families. Gale winds and towering waves broke the island in two and tore away the hotel, casinos, summer homes and all the island's trees.
"The wind blew a perfect hurricane; every building upon the island giving way, one after another, until nothing remained … ," an eyewitness told The Daily Picayune on Aug. 14, 1856. "The sea waved over the whole island. Those who were fortunate to find some object to cling to were seen floating in all directions."
More than 200 people drowned or were crushed by wreckage. The island, cut through, began to splinter further, eventually giving shape to Whiskey and three other islands - East, Trinity and Raccoon.
Had Derniere not been in the hurricane's path, the destruction would have been far worse on the mainland, where several fishing communities dotted the bayous northward to Houma. The hurricane made abundantly clear that barrier islands were a treacherous place to live, but it wasn't understood for another century the protective role they play. By then, nearly all of the state's barrier islands were in danger of slipping away.
Louisiana State University oceanographer Joe Suhayda sounded the alarm in the early 1990s. With the help of computer scientist Vibhas Aravamuthan, Suhayda produced models that altered or erased the barrier islands under several storm scenarios. Even small changes to the island's shapes and heights had big implications, they found. Shrink an island a bit and hypothetical storms strike the mainland harder, faster and with taller waves.
A Category 3 hurricane thrown at the more robust Louisiana coastline of 1930 would have left Houma high and dry, according to their model. The same hurricane let loose in 2020, when much of the barrier chain would have eroded away, put the city under three feet of water.
Remove Whiskey and its neighbors, and 1992's Hurricane Andrew swamps Cocodrie with an extra foot of water, the modeling showed. But bulk the islands up a bit, giving them a touch more height and width, and Andrew's flooding would have been cut by as much as five feet.
"Thinking about these islands as though they were gone - that put a lot of emphasis on them and the projects to save them," Suhayda, now retired, said in April.
Just as the islands' importance was becoming clear, so was their rate of loss.
Posted on Fri, July 27, 2018
by By TRISTAN BAURICK, NOLA.com | The Times-Picayune