No major US city will be fully submerged by 2050, but several will lose significant land to permanent flooding. Sea levels along US coastlines are projected to rise 10 to 12 inches on average by 2050, with some areas facing far more. An estimated 4.3 million acres of land, nearly the size of Connecticut, will be underwater by mid-century, threatening $35 billion worth of real estate and displacing roughly 2.5 million Americans from their homes.
The cities at greatest risk aren’t spread evenly across the map. The Gulf Coast and parts of the East Coast face disproportionate danger, driven by a combination of rising oceans and sinking land.
Why Some Cities Face Far More Than 12 Inches
The 10-to-12-inch national average obscures dramatic regional differences. The Gulf Coast is expected to see sea level rise 4 to 6 inches higher than the national average, while the East Coast will run slightly above average as well. The West Coast and Hawaii, by contrast, will experience 4 to 6 inches less than average.
The reason is that sea level rise isn’t just about melting ice adding water to the ocean. In many vulnerable areas, the land itself is sinking. Groundwater pumping, oil and gas extraction, and the natural compaction of sediment all pull the ground downward. When the ocean rises and the land drops simultaneously, the effect compounds. Norfolk, Virginia illustrates this perfectly: its measured rate of sea level rise is the highest on the East Coast at over 5 millimeters per year, and researchers at the Virginia Institute of Marine Science recommend planning for a 2.1-foot rise by 2050, more than double what a simple projection would suggest.
Changes in ocean circulation also play a role. The Atlantic’s major current system is expected to weaken in coming decades, which pushes water levels higher along the Northeast and Southeast coasts.
The Gulf Coast Cities at Greatest Risk
Louisiana and southeast Texas face the most severe outlook of any region in the country. The combination of soft, compacting soils, heavy oil and gas extraction, and direct exposure to Gulf hurricanes makes this stretch of coastline uniquely vulnerable.
New Orleans already sits largely below sea level and depends on an aging levee system for survival. Research published in Nature identified New Orleans as one of the cities with the most disproportionate economic exposure, meaning the neighborhoods most likely to flood tend to be lower-income areas with less capacity to recover. Terrebonne Parish, south of New Orleans, could see 77 percent of its total acreage flooded by 2050, potentially submerging 5,700 buildings.
Port Arthur, Texas faces a similar profile: low elevation, sinking land, concentrated industrial infrastructure, and flood-vulnerable neighborhoods where home values sit below the citywide median. Galveston and Texas City, both on the upper Texas coast, are also among the 32 major coastal cities flagged by researchers as facing significant inundation risk.
The East Coast’s Most Vulnerable Areas
Norfolk and Virginia Beach sit at the center of one of the fastest-sinking stretches of the Atlantic seaboard. Norfolk is home to the world’s largest naval base, and chronic flooding already disrupts roads and neighborhoods during ordinary high tides. The safe planning projection of 2.1 feet of rise by 2050 would transform what are currently nuisance floods into routine inundation of low-lying streets and infrastructure.
Atlantic City, New Jersey is another standout. Like New Orleans and Port Arthur, the flooding exposure falls hardest on lower-value properties, concentrating economic harm among residents least equipped to absorb it. Jersey City, just across the Hudson from Manhattan, was specifically added to a major Nature study of disappearing coastal cities because of its importance as an urban center and its proximity to New York City’s flood zone.
North Carolina’s Outer Banks represent a different kind of vulnerability. Dare County, a narrow barrier island community, could see 27 percent of its land at risk of flooding by 2050. That translates to $875 million in real estate and buildings. Barrier islands are especially fragile because they’re thin strips of sand with water on both sides, and even modest sea level rise can reshape them dramatically.
Miami and South Florida deserve particular attention. The region sits on porous limestone, which means seawater doesn’t just come over seawalls. It seeps up through the ground itself, infiltrating foundations and freshwater supplies in ways that conventional flood barriers can’t prevent.
What “Underwater” Actually Means
When researchers talk about cities being “underwater,” they’re rarely describing a sudden Hollywood-style submersion. The process is gradual and takes several forms. Permanent inundation means land that is below the daily high tide line and stays wet all the time. Chronic flooding, sometimes called high-tide flooding, refers to areas that flood repeatedly during high tides, storms, or heavy rain, even without a hurricane. NOAA defines high-tide flooding as beginning when water levels reach roughly 1.5 to 2 feet above the average high tide.
For most cities, the 2050 reality will look like chronic flooding that makes neighborhoods increasingly unlivable rather than a single catastrophic event. Streets that flood a few times a year today may flood dozens of times a year by 2050. Saltwater will corrode infrastructure, contaminate drinking water wells, and make insurance unaffordable long before the ocean permanently claims the land.
The Scale of Property and Population at Risk
Across the country, roughly 2.5 million people in 1.4 million homes currently live in areas projected to face severe coastal flooding by 2050. That estimate assumes nations follow through on their existing pledges to reduce carbon emissions, meaning it’s closer to a best-case scenario than a worst-case one.
The $35 billion in at-risk real estate is spread across nearly every coastal state, but the losses concentrate in a handful of places. Louisiana, South Florida, the Carolinas, and the mid-Atlantic corridor account for the bulk of the exposure. The economic pain extends beyond property values: flooded roads cut off businesses, damaged utilities cost municipalities millions to repair, and declining property tax revenue hollows out local government budgets.
Which Cities Are Taking Action
Some of the most vulnerable cities are investing heavily in adaptation. New Orleans has rebuilt and strengthened its levee system since Hurricane Katrina, though the system was designed for conditions that may be outdated by 2050. Galveston and the Houston region have pursued a massive coastal barrier system, sometimes called the “Ike Dike,” to shield Galveston Bay from storm surge. Miami has committed billions to raising roads, upgrading stormwater systems, and installing pumps throughout the city.
Norfolk has become a national test case for military-community resilience planning, given the naval base’s strategic importance. The city is elevating homes, redesigning drainage systems, and in some cases buying out properties in the most flood-prone areas.
These projects can buy time, but they face a fundamental challenge: sea level rise doesn’t stop in 2050. Infrastructure built to handle 12 inches of rise may be overwhelmed by the 2 to 4 feet projected for the end of the century. Cities making investments today have to weigh how much protection to build now against how much more they’ll need in 30 or 50 years, all while the cost of doing nothing keeps climbing.
Cities to Watch Beyond the Usual List
Foster City, California, a small community built on reclaimed marshland in the San Francisco Bay, was flagged alongside New Orleans and Atlantic City for its disproportionate flood exposure relative to home values. Charleston, South Carolina already experiences some of the most frequent high-tide flooding on the East Coast, with flood days increasing sharply over the past decade. Annapolis, Maryland and Savannah, Georgia face similar trajectories: low-lying historic downtowns built at the water’s edge centuries ago, now increasingly at odds with the rising tide line.
The broad pattern is clear. If you live in a Gulf Coast or East Coast city that sits less than a few feet above today’s high tide, the water is coming closer. The question isn’t whether these cities will be affected by 2050 but how much of them will remain dry enough to function as they do today.