The Urban U.S. could look very different in the year 2100, in part because thousands of cities might be rendered virtual ghost towns. According to findings published in Nature Cities, the populations of some 15,000 cities around the country could dwindle to mere fractions of what they are now. The losses are projected to affect cities everywhere in the U.S. except Hawaii and Washington, D.C.
“The way we’re planning now is all based on growth, but close to half the cities in the U.S. are depopulating,” says senior author Sybil Derrible, an urban engineer at the University of Illinois Chicago. “The takeaway is that we need to shift away from growth-based planning, which is going to require an enormous cultural shift in the planning and engineering of cities.”
Derrible and his colleagues were originally commissioned by the Illinois Department of Transportation to conduct an analysis of how Illinois’s cities are projected to change over time and what the transportation challenges will be for places that are depopulating. As they got deeper into the research, though, they realized that such predictions would be useful to know for cities across the entire U.S.—and not just for major ones, such as New York City, Chicago and Los Angeles. “Most studies have focused on big cities, but that doesn’t give us an estimation of the scale of the problem,” says lead study author Uttara Sutradhar, a doctoral candidate in civil engineering at the University of Illinois Chicago.
The authors analyzed data collected from 2000 to 2020 by the U.S. Census and the American Community Survey, an annual demographics survey conducted by the U.S. Census Bureau. This allowed them to identify current population trends in more than 24,000 cities and to model projections of future trends for nearly 32,000. They applied the projected trends to a commonly used set of five possible future climate scenarios called the Shared Socioeconomic Pathways. These scenarios model how demographics, society and economics could change by 2100, depending on how much global warming the world experiences.
The authors’ resulting projections indicated that around half of cities in the U.S., including Cleveland, Ohio, Buffalo, N.Y., and Pittsburgh, Pa., are likely to experience depopulation of 12 to 23 percent by 2100. Some of those cities, including Louisville, Ky., New Haven, Conn., and Syracuse, N.Y., are not currently showing declines but are likely to in the future, according to the findings. “You might see a lot of growth in Texas right now, but if you had looked at Michigan 100 years ago, you probably would have thought that Detroit would be the largest city in the U.S. now,” Derrible says.
Regionally, the Northeast and Midwest will most likely be the most heavily affected by depopulation, the authors found. And on a state level, Vermont and West Virginia will be the hardest hit, with more than 80 percent of cities in each of these two states shrinking. Illinois, Mississippi, Kansas, New Hampshire and Michigan could also see about three quarters of their cities decline in population.
While the authors’ analysis of current trends found that 43 percent of the more than 24,000 cities are losing residents, around 40 percent are now growing, including major cities such as New York City, Chicago, Phoenix and Houston. In general, though, the places that are projected to most likely gain population by 2100 tend to be located in the South or West.
The new analysis does not explore the factors that are driving the projected trends. But Sutradhar says there is probably a complex mix of variables at play that differ by location, including the rising cost of homes in some places, the decline of industry, lower birth rates, different levels of state taxes and the impacts of climate change.
Justin Hollander, an urban planning scholar at Tufts University, who was not involved in the research, says that the new study’s methods were sound and that the findings are original. “I have never seen a national study that looked so far into the future,” he says. He warns, however, that making specific projections this far in advance is “pretty reckless,” given the amount of uncertainty the future holds.
He appreciates, though, that the paper calls attention to future depopulation in general, which he agrees the data do support. “These are not isolated problems to the Detroits of the world,” he says. “Depopulation is everywhere, and the paper is right to demand that cities face this fact and begin to honestly prepare for this possible future.”
The authors hope that their paper serves as a wake-up call to policy makers to begin moving away from growth-based planning and to start finding place-specific solutions for cities that are likely to depopulate in the years ahead. “We should see this not as a problem but as an opportunity to rethink the way we do things,” Derrible says. “It’s an opportunity to be more creative.”