LEEVILLE, La. -- This is where the mainland ends in southern Louisiana -- at least for now.
You get here by following an old road that abruptly ends at an expanse of marshy water, which is moving in on the land at one of the fastest clips in the world, according to scientists. Residents note that the road, known as LA-1, now leads in more directions than just north and south. It's also sinking.
Its two lanes reach into this part of the state, about two hours south of New Orleans, through treeless fields and spongy marshes that sit near sea level. With little height to spare, the combined effects of subsidence and rising oceans, measured at over an inch every three years, are obvious.
"The Gulf of Mexico has basically gotten closer to us," said Windell Curole, who manages the South Lafourche Levee District. He suspects that without a major government effort, this sprawling area could sink below the surface within two or three generations. "We can see the trend, and the trend is not good."
After a hurricane in 1893 slammed the coast with killing winds and waves, his great-grandparents retreated to higher ground 11 miles inland, he said. Their refuge was Leeville, which earlier this century hosted cotton fields and oak trees. Now it's open water dotted with grass tufts after the water rose 4 feet. Most of that, according to Curole, has resulted from a persistent sinking of the ground.
In the past 50 years, the presence of marshy grasses has been receding, replaced by open water, which increasingly is submerging fence posts, oil wellheads and brick-built tombs of people that were once built safely above the water level. Clumps of grass used as landmarks by fishermen can disappear over the length of a season, or even within a few weeks. Meanwhile, canals are growing wider.
"It's remarkable," Curole said. "It's just remarkable how bad it is."
Now at the water's edge, Leeville is the site of a major effort at climate adaptation. In 2011, an elevated expressway was opened to better connect the mainland at Leeville with Port Fourchon, a key oil and gas facility located on a fortified hunk of land that's reached by driving over 11 miles of broken marshland toward the Gulf.
Ignored warnings and drowned chickens
The $420 million expressway replaced the last leg of old LA-1, which reached Port Fourchon by skirting a thin line of land that scientists believe will be underwater later this century. The old road was severed at Leeville. The rest of it resumes on the other side of a marshy expanse, snaking the rest of the way out to the port like a severed tentacle.
Before the project, the low highway was already experiencing more floods that threatened to stall the use of rig cranes, helipads and other operations at the port, which provides about 90 percent of the support services used by deepwater energy companies in the Gulf. Climate change was threatening a key piece of the nation's energy infrastructure.
But the new expressway alone won't keep the port open during an era of rising water, local advocates say. Storms can still stop traffic because an 8-mile stretch of LA-1 leading to the new project is near sea level. If it floods -- and it does -- freight trucks and workers can't reach the fortified expressway.
This old stretch of the road bumps along the muddy edge of a canal called Bayou Lafourche, and it's so close to the water that shrimp boats moor alongside it like parked cars. Parts of the road can flood when a stiff wind from the south pushes Gulf water toward the coast at high tide, residents say.
It totally disappears during a big storm.
When Hurricane Isaac struck in August 2012, the surge reached the doorknob of Randy Borne's front door; his house sits on 5-foot pilings. Dressed just in shorts, he was wearing more tattoos than clothes during a recent visit to his yellowish one-story home, where his great-aunt lived when he was a kid. He grew up in a similar house, only blue, about 100 yards away. He catches crabs to sell, and on bad days their habitat invades his.
His house, which rests on the side of LA-1, has been flooded by several feet of water at least three times in the past nine years. The state ordered a mandatory evacuation during Isaac. Borne, 34, ignored it. He also lived through Hurricane Katrina in 2005; his chickens and ducks weren't as lucky.
"They drowned in the house," he explained. "So I cooked 'em up right away."
'There would be no land'
A mile or two up the road, a lock stops storm-driven water from sweeping through the bayou and entering a circle of levees around the town of Golden Meadow. Everything outside the protective system floods. So the 8-mile stretch of land between the barrier and the elevated section of LA-1 at Leeville will eventually be underwater again.
Currently, that section of the road is inundated in places 3½ days a year, on average, according to the National Oceanic and Atmospheric Administration. That's expected to climb rapidly as relative sea-level rise of 9.24 millimeters a year overtakes the area's negligible elevation.
NOAA predicts that within 15 years, the lowest parts of the road will be submerged 30 times a year, "even in the absence of extreme weather." By that time, the water around here will be more than 5 inches higher.
By 2066 or so, the road will be closed year-round, the agency estimates.
"It's low-lying and losing ground fast," Stephen Gill, a senior scientist with NOAA, said of the land around the old road. Doubling the length of the elevated expressway, as a local group is proposing, would be "buying quite a bit of time" for the port, he added.
Residents around here won't be as lucky.
"By 2100 there would be no land," Gill added. "You would have a very long causeway going out into the middle of the ocean, almost, and isolated out there would be the port, but without any land around it. But you would have the port, and it could function."
In the shorter term, it's "highly probable" that the 8-mile strip of low road could experience two scenarios that make it impossible to reach the existing expressway leading to Port Fourchon, resulting in a three-month closure of the port, according to a 2011 report by the federal Department of Homeland Security. The first would result from prolonged inundation from sea-level rise; the second scenario involves a storm that wrecks the road.
The government paper, which was funded by the LA-1 Coalition, a group of oil and gas companies, local businesses, and the port authority, says the extended closure has "a near 100 percent probability" of happening by between 2030 and 2040. The price of shutting the port down is high -- resulting in $7.8 billion in lost gross domestic product -- but it wouldn't cripple the national economy, the study found.
Plans are already underway to replace the vulnerable strip of LA-1 with a 22-foot-high expressway through nearby marshland, about doubling the length of the existing expressway connecting Leeville with Port Fourchon.
Henri Boulet, executive director of the LA-1 Coalition, said finding the funding, about $345 million, has been harder than for the previous project, which opened in 2011 after just 3½ years of planning and construction. The state paid for most of it; Washington and tolls also contributed.
"I don't think this [Obama] administration wants to fund an oil and gas road," Boulet said, also noting that congressional earmarks, which provided $53 million for the first leg, are now banned.
That puts him in the notable position of advocating for a climate adaptation project on behalf of oil and gas companies, and finding resistance from an administration that has made unmatched strides on climate policy, including infrastructure resilience.
Boulet, a Democrat, adds that it can be "awkward" to discuss climate change with his employers at the port and local politicians, who tend to be Republicans. Still, he tells them that the climbing oceans are threatening the road.
"They all say, 'We know it,'" Boulet explained. "The Democratic reply would be, 'Absolutely, it's gonna impact all of us.' The Republican response is, 'I know.' There's no elaborating on it."
Not everyone thinks the elevated road should be built. Some believe it's a form of "climate denial" that rejects the geologic facts of the sinking Louisiana delta.
Be real and leave now
Persisting with policies that provide roads, fund coastal restoration and construct huge flood defense systems is a kind of psychological trick that makes people feel safer than they are, said Edward Richards, a law professor at Louisiana State University.
He said you can't "restore" a coast that's disappearing by the day, amounting to 1,883 square miles of lost land between 1932 and 2010, according to the U.S. Geological Survey. That's the size of Delaware. Big chunks can vanish even faster. Erosion caused by hurricanes in 2005 and 2008 swept away an area of land the size of Chicago.
And it's been sinking since long before then.
The Louisiana coastline has hosted 16 different deltas over the last 7,000 years, each one being built up by sediment deposited by the Mississippi River, according to geological research. Each one sank when the river shifted. Core samples show barrier islands 35 feet underground and evidence of cypress swamps 25 feet down.
Subsidence today is probably worse than its historical analogs. The river has been walled, leveed and dammed to prevent flooding. That's reduced its sediment delivery to the state's coastal plain by about 50 percent, shooting the silt far into the Gulf instead.
Richards said public officials, environmentalists, and oil and gas companies are largely ignoring these facts.
"You're gonna have to move," he said, referring to the state's coastal population, arguing that subsidies in federal flood insurance and other government expenditures have encouraged people to live in dangerous places.
"I don't think we'll make any political choices to actually retreat," he acknowledged. "We'll just sit and wait for the risk to accumulate."