This Is What America Could Look Like When Our Coasts Are Under Water
Rising sea levels could be an opportunity for social change—or a dystopian hellscape.
Soldier’s Grove is a small town of fewer than 600 people located near the Kickapoo River in Wisconsin. The Kickapoo is not a genial body of water. In 1907, the river flooded, dumping record amounts of water into downtown Soldier's Grove. Then it did so again in 1912, 1917, 1935, 1951, and 1978. The town saw 25 nationally declared flood disasters in a 38-year period.
“Each time there was very little advance warning,” the county sheriff said in a Federal Emergency Management Agency (FEMA) report. “People woke up at night with three to four inches of water already in their homes.”
In 1937, the residents of Soldier’s Grove decided they'd had enough and petitioned Congress to help them fund a solution. It took 32 years, but in 1975, the town got a proposal for a $3.5 million levee to protect their $1 million worth of property. After considering the math, the citizens of Soldier’s Grove came up with a different plan for the money: They would move the town to higher land.
By 1983, the relocation was complete. And Soldier’s Grove hadn’t just rebuilt, it had made improvements. The business district became the country’s first "solar village," in which all commercial buildings had to get at least half of their energy from the sun, a radical gesture for 1983. The medical center, the pharmacy, the library, the fire station, the post office, and more, all ran on solar—and still do.
Soldier’s Grove is an early example of managed retreat: a proactive, intentional shift of civilization away from an environmental threat. Today, managed retreat is a potential strategy for survival in the face of rising sea levels from our rapidly changing climate. While most major cities talk only about walls and infrastructure to protect against the encroaching sea, Soldiers Grove is a model of how retreat can be a cost-effective option, and a chance to do something more than just run away.
The question isn't whether we will retreat, it's how we will retreat.
In the past 30 years, 1.3 million people have vacated their homes through managed retreat. Most of the time, individual houses are bought out by government agencies, like FEMA, in areas hit by repeated climate disasters. But sea levels are continuing to rise, and could even be accelerating, according to a recent NASA study. By 2100, 72 to 187 million more people could be displaced, forcing us to rethink our piecemeal strategies.
Those working in climate science, sociology, urban planning, and law are grappling with how managed retreat can be more than an option of last resort. Scientists and policy makers envision that if carefully planned, retreat could be a tool to reckon with social and racial inequalities, and the reality that global warming will exacerbate these injustices.
Depending on how we do it, we face very different coastal futures. In one scenario, our coastlines will be dotted with derelict ruins—the haunting remains of communities that weren’t given a chance to get out of harm’s way. Cities will exist behind walls built that protect from the ocean, and there will be no access to the shoreline.
In a more egalitarian vision, U.S. shores could be reclaimed as public land. A national shoreline could serve as a natural buffer to the ocean, and if paired with affordable housing, community investment, and employment, moving away from the coasts could promise survival but also, better quality of life.
“The question isn't whether we will retreat, it's how we will retreat,” said A.R. Siders, an environmental fellow at the Harvard University Center for the Environment. “In that, we have a lot of choice and a lot of opportunity.”
The word “managed” is crucial to the concept of true managed retreat. Retreat alone is what happens when coastal areas are hit too hard by a disaster and become unlivable. More than a decade after Hurricane Katrina, New Orleans still has tens of thousands of abandoned homes. “They didn't want to live there and they moved away,” Siders said. “Well, that's retreat. It doesn't have any management. There's no support system. There's no assistance. People go on their own.”
The best and simple version of managed retreat is when local and federal governments step in to help and provide resources to people who can’t move on their own, and want to go.
Moving people ahead of any actual disaster might sound extreme, but in fact, a serious conversation about retreat is happening decades too late, according to Susanne Moser, a researcher on climate adaptation affiliated with Stanford University and the University of California-Santa Cruz. Soon, it won’t just be clusters of houses that need to be bought. Overnight, half of a city—say Charleston, South Carolina—might have to move. We currently have no national framework to deal with this.
“What's so mind-boggling is that half of the U.S. population, and more than half of GDP, come out of coastal counties, and we don't have an idea of how we're addressing accelerating sea level rise, against which we cannot protect forever,” Moser said.
But in March of this year in New York City, $500 million was dedicated, not to retreat and relocation, but to a wall to protect from rising water. New York is among other coastal American cities pledging to build infrastructureto shield themselves.
Even if a wall works for a specific area, it shifts erosion and flooding to either side of the wall, Siders said. If New York City erects a wall around itself, it doesn’t stop flooding, it just pushes it somewhere else. “And we can't put a wall around the entire United States,” she said. “So everywhere we build a wall and choose to protect one place, we're putting another place at risk.”
Moser agreed, saying it’s also wildly expensive, aesthetically garish, ecologically damaging, and probably won’t work everywhere. In Florida, the water can come also from below, so "you’d end up filling in that nicely protected bathtub you’ve created,” she said.
Building walls also summons images of a dystopian future. "You could end up with these walled city-states and then everyone else is just left to fend for themselves," said Liz Koslov, an assistant professor at the UCLA Department of Urban Planning and Institute of the Environment and Sustainability. "These protected cities would be seen as too big to fail and increasingly become the provinces of the wealthy.”