Once a thriving wetland, Barataria Bay in Louisiana is now mostly covered by open water. Photos by Erika Larsen

One day last July, a group of us were in an open boat racing across Barataria Bay, south of New Orleans, about 100 miles northwest of where BP’s Macondo well had started gushing oil three months before.

Oil wasn’t hard to find; later that afternoon we would discover our own dead pelicans and see the necrotic fringe of the burned-looking marsh where the oil first hit. At the moment, though, we were focused not on the oil but on Ryan Lambert, the captain of the boat and proprietor of Cajun Fishing Adventures, a big man who in turn was focused on the miles of open water spread out in front of us.

"Look at my GPS," he said. "It still shows all this as land. Not long ago this was 6.3 miles of grass. Now I can point my boat right over those 6.3 miles and never see a blade."

Lambert pulled up to a spot where wooden posts thrust up out of the water. As we approached, dozens of huge, black-and-white frigate birds lifted off them. I had never seen that many frigate birds outside of Central America. They rose in slow motion, beautiful and gawkily elegant, as Lambert cut the boat’s engine.

As we drifted, he explained that the posts were not just perches for the birds but a kind of grave marker for a bayou camp. "Locals would come here -- right here," he said, "and they would fish and they would trap and hunt and they would have crab boils and shrimp boils and they would walk out their back door and hunt ducks. And now look -- there’s not a blade of grass for miles."

It was true; we might have been in the middle of a lake. In every direction we could see places where land used to be and where we now saw only clouds reflected in the water. In the distance, small strands of marsh islands barely kept their heads above the tide, just the hair of grasses showing. In spots we’d passed earlier you could see dead trees going under.

"This is not something that is happening over centuries," Lambert continued. "Just a few years ago I could look out for miles here and just see grass. Now it’s all underwater. Whatever the reason -- sea level rise from warming, the land sinking in part because of oil extraction -- it really doesn’t matter. The point is that it’s happening."

I knew the seas were rising, but before I came to Louisiana I hadn’t known that the seafloor was sinking, through a process called subsidence. Sediment dumped by the Mississippi River weighs down the floor of the Gulf, causing it literally to sink. And as the land sinks, saltwater invades, killing cypresses and other plants that help stitch the wetlands together. Louisiana’s erosion rate is the worst in the country, with the equivalent of 60 football fields of wetlands being lost every day. Which means that if you stand in one place long enough, you might actually see it turn from land to water.

Among the things killing the wetlands are straight lines. Nature, of course, isn’t very fond of straight lines, and creeks always used to wind sinuously through the grasses, replenishing the wetlands with sediment. But humans long ago decided that winding was not a good way to travel. They dredged straight canals, shunting sediment and nutrients out to sea. Other straight lines here show the paths of the tens of thousands of miles of pipeline that traverse the wetlands, carrying oil and gas from offshore rigs to shore and unintentionally ushering saltwater deeper into the marsh.

That morning I had been lucky enough to get up in a helicopter and see from the air the same bay we were now floating on. Flying directly over these wetlands, you could see the straight pipelines crosscutting the marsh, as well as the rectangular holes of water, called keyholes, where oil rigs used to be. You could also see the straight lines of the canals, superimposed on the wild marsh like a grid.

I thought back to how, as a kid, I loved to go to the beach to play on the small sandbar islands that revealed themselves at low tide and how, when the tide started to come back in, I would aid the rising waters by digging lines across the sandbars with my heel, creating canals for the incoming tide to run through. I would often dig about a dozen of these lines, flooding the sandbar islands before their time. Something similar was going on here on an enormous scale.

***

Lambert and I had met just over 24 hours earlier, when I pulled into the hunting and fishing lodge he owns in Buras, Louisiana. The lodge was half empty, which seemed odd given that I’d seen several
No Vacancy signs on the way down from New Orleans.

"I’m the only lodge around that isn’t booked up," Lambert said. "The rest of them are filled with BP workers. But I’d rather meet interesting people than whore myself out to BP."

Which was why he was taking out people like me and the other folks who had come down for the day to crowd onto his boat. Also aboard were a radio personality known as "the Ocean Doctor" and an NBC cameraman who trailed him like a pilot fish. Two of us on the boat were professors who lectured for a living, but we were learning that we had nothing on the boat’s captain. Lambert, it turned out, was not just a man with energy and passion. He was also a man with a cause.

As we bobbed on the water he talked movingly about the loss of animal habitat, the loss of human culture and livelihoods that have accompanied the disappearance of the marshes, which had made this one of the most biologically productive estuaries in the world.

The shrinking of the marshes also meant a diminished defense against the spilled oil. The barrier islands and outer marshes have always been the frontlines of defense against hurricanes, and now they were the frontlines against the oil, keeping it from working its way into the heart of the wetlands. A second defense, Lambert explained, was the Mississippi itself, which had done more than its part to keep the oil at bay, its massive outward flow pushing back against the Gulf’s inward surge. "The river protects these marshes, and it’s also what made them," he told us. "It’s what made Louisiana -- the sediment it brought here, the nutrients that helped grow these wetlands." The river would still be doing this if it were not hemmed in by the levees, he told us. "What we have to do is redistribute," he said.

He didn’t mean the wealth. He meant the water. "Free the Mississippi," it turned out, was Lambert’s rallying cry. He was not talking about radical freedom here, since without the levee his lodge would be underwater. What he was really looking for was a series of diversions, so the river could feed the marsh at various points rather than dump all it had to offer in one great slug out in the Gulf.

"All we have to do is let the river go through these marshes like it did for eons of time, when it built Louisiana," he said. "We could start slow, maybe one diversion channel, but that would be sufficient to bring in the freshwater and to grow the freshwater aquatics and to keep the saltwater at bay and start to rebuild Louisiana."

From the helicopter I had seen the Mississippi from above. The river is corralled by its levee, segregated from the marshes and forced to wind down to the Gulf without once interacting with the wetlands around it. The sight was shocking: the great freshwater torrent running home toward salt. The bayou world of marsh grasses and creeks and straight, man-made canals was one thing, but the great, brown, snaking Mississippi, carrying its sediments out to sea, looked like a whole other ecosystem laid on top of it. From the air, you could almost see geology at work, see how the Mississippi had dumped its nutrients for millions of years and how the land had spread southward from the Delta, extending itself in miles and miles of watery grasslands, which in turn became a spawning ground for young fish and home to oysters and shrimp and millions of birds. Green jigsaw pieces of grass fit with blue pieces of water while a river ran through this already watery world.

In Lambert’s vision the river would spread out more naturally, like a watery hand, feeding the marshes with the nutrients it gathers during its powerful crawl from Minnesota down through the country’s middle and finally to the Gulf. Of course, far from being "natural," his proposal would require a massive engineering project on the scale of building the levee itself. But it would be engineering toward a different end, toward releasing the river, to an extent, and letting it do what it once did naturally.

"It is such a beautiful solution, and it doesn’t just solve the problem of massive erosion," Lambert continued. "It protects us from hurricanes and oil and it tackles the problem of the dead zone in the Gulf. Right now we have a dead zone the size of New Jersey where the Mississippi dumps all the crap from a thousand farms -- the manure and fertilizers and insecticides -- along with the nutrients. This creates algae blooms and removes the oxygen and kills sea life, too. But if this same nutrient- and fertilizer-rich water runs into the marshes, the result will be completely different. Everybody says, 'We got to stop the nutrients; we got to stop the fertilizers,' but you know, we really don’t. All the wetland plant life will use the nutrients, filtering the leftover fertilizer, and when it comes out the other end it will be pristine, crystal-clear water. If we let the river run through there like it’s supposed to, we will be using those nutrients while also cleaning up the dead zone. We think we’re smarter than Mother Nature, but we’re not. We can sometimes outsmart her for a lifetime or two, but she’s coming to get us eventually, and she’s coming back to haunt us right now."