Rising seas will swallow New Orleans. People need to start relocating now, scientists say

Atchafalaya Basin, Louisiana, is a vast wetland. (Dukas/Universal Images Group Editorial/Getty Images via CNN Newsource)

New Orleans is locked into a watery future which could see it surrounded by ocean as early as this century, according to a new expert analysis, which says the city must start the relocation process now to avoid chaos.

The paper’s conclusions are stark, but it’s no secret that New Orleans is highly vulnerable to rising seas as the planet warms. Coastal Louisiana is one of the lowest lying regions in the world, and New Orleans, a city of 360,000 people, is particularly exposed. It sits in a bowl-shaped basin, mostly below sea level, in the middle of a rapidly shrinking delta.

The city is almost entirely surrounded by wetlands, which act as a buffer against hurricanes and storm surges. These are fast disappearing, however, as humans drain them for development, dredge canals in them for the oil and gas industry and construct river levees, depriving them of the sediments that stop them being submerged. Since the 1930s, Louisiana has lost around 2,000 square miles of wetlands.

Coastal Louisiana faces sea level rise of around 10 to 23 feet, according to the analysis published in May in the journal Nature Sustainability. The impacts will be bleak: around 75 per cent of its remaining wetlands are set to be lost and its shoreline could retreat inland by up to 62 miles, the scientists found.

The region has “crossed the point of no return,” the paper’s authors wrote, adding New Orleans “may well be surrounded by the Gulf of Mexico before the end of this century.” They argue the city must seize the opportunity to develop strategies for relocation that could make it a model for places facing a similar fate.

Rising seas are coming for coastal towns and cities all over the world, from New York and London to Bangkok and Shanghai. “The main questions are how soon those futures will come, and how they will play out,” said Benjamin Strauss, CEO and chief scientist at Climate Central, a climate research non-profit.

To map Louisiana’s future, the report’s scientists looked into its past. One of the authors identified an ancient shoreline roughly 30 miles (48 kilometres) north of New Orleans, which formed around 125,000 years ago when temperatures were similar to today, but the oceans were at least 10 feet higher.

“It’s very likely that sea level will rise to that elevation in the future,” said Torbjörn Törnqvist, a report author and a geology professor at Tulane University. The question is what should be done and when.

People are already leaving coastal Louisiana and have been for decades, said Brianna Castro, a study author and assistant professor of urban sustainability at Yale School of the Environment.

Since Hurricane Katrina — which slammed into Louisiana in 2005, killing nearly 1,400 people — New Orleans has lost around 25 per cent of its population. The retreat has been a “pulse-like” process, where every major storm or flood prompts a spike in departures, Castro said.

The storms the city faces are only likely to get harder to endure. Approximately 99 per cent of the population in New Orleans is at high flood risk, according to a recent study. “When another Katrina-like hurricane strikes the city, almost everyone would experience flood damages,” said Wanyun Shao, an author of that study and associate professor of geography at the University of Alabama.

Failing to implement a carefully managed relocation process risks a “chaotic” retreat which will come at a high cost, especially for the city’s poorest, the paper’s authors argue. As the population drops, it will entrench existing inequalities, Törnqvist said. The tax base erodes, services get worse, insurance premiums skyrocket and homes lose value.

People may decide to stay and adapt in place, but the more money they sink into trying to flood-proof their lives, the less they will have to relocate in the future, Castro said. “If the writing is on the wall that we need to go eventually, do we want to wait until people’s resources are exhausted and there’s a crisis?” she asked.

There is precedent for relocation. The city of Kiruna in Arctic Sweden is being slowly swallowed by the iron ore mine upon which it was built. As the mine expanded, buildings fractured and some collapsed.

Kiruna is now in the midst of a decades-long relocation process, which was voted for in 2004 and is expected to be finished in 2035. Last year, the town transported its more than 100-year-old church to the new city on a specially designed trolley. The new city centre should be ready next year, said Clara Nyström, Kiruna’s municipal heritage officer.

Relocation has not been easy, however. Rents have increased, which is difficult for residents, and there are concerns culture and community may be lost. “It is a big sorrow to leave everything, and I think that is important to understand that,” Nyström said.

Castro is optimistic that building a New Orleans 2.0 on safer ground can be done without sacrificing culture. Build a great city and people will come, she said, “you don’t have to lose the spirit of New Orleans.”

Others are less optimistic. Beverly Wright, whose family in New Orleans goes back eight generations, fears relocation could fracture the city.

“The culture that we have has grown out of life experiences and neighborhoods, so anytime you break up a neighbourhood, you lose things,” said Wright, who is the founder and executive director of the Deep South Center for Environmental Justice.

She’s a scientist and does not doubt sea level rise is an existential threat, but she is deeply concerned about how a relocation would play out.

“I have no hope in the establishment being considerate of Black people… I’m looking at what they did to us after Katrina,” Wright said, referring to the widely-criticized government response to the hurricane. She fears generations of Black people will be forced to start again from scratch “because they have nothing if the land is taken from them.”

For now, there does not seem to be a huge appetite among policymakers to really start thinking about relocation, Törnqvist acknowledged.

There have been efforts to buy the region more time. In August 2023, ground broke on a vast sediment diversion project to boost the wetlands and help safeguard south Louisiana from storms and rising seas.

In 2025, however, it was cancelled by the state’s Republican Governor Jeff Landry, citing high costs and damage to fisheries. This decision “effectively means giving up on extensive portions of coastal Louisiana, including the New Orleans area,” the report authors wrote.

Gov. Landry’s office did not respond to a request for comment.

Törnqvist and Castro are keen to emphasize their paper is not all doom and gloom. A carefully planned relocation could be an opportunity for New Orleans to be a leader in sustainable development and coastal restoration.

The exceptional vulnerability of the Gulf Coast offers a window into what may await other coastal communities this century. The sea may claim the land earlier here than elsewhere, Törnqvist said, “but what happens here now is what’s going to happen in other places.”