Since 1989, the Federal Emergency Management Agency has bought and demolished more than 43,000 homes in flood-prone areas, a strategy meant to make communities less vulnerable to disasters. But which homes get selected for the buyouts depends as much on the wealth of the affected neighborhoods as on the actual level of danger that those areas are exposed to, according to a study published Wednesday in the journal Science Advances.

The findings raise concerns that limited federal funding for adapting to climate change isn’t helping the areas that need it the most, according to the paper’s authors.

“Who benefits?” asked Katharine Mach, a professor at the University of Miami’s Rosenstiel School of Marine and Atmospheric Science and the paper’s lead author. “There is a real potential for our responses in a changing climate to make the fat cats fatter, so to speak.”

The paper is the latest evidence that even as the effects of global warming worsen, the United States is increasing its exposure to the dangers that arise from climate change.

In many coastal states, flood-prone areas continue to see the highest rates of home construction. At the same time, the number of Americans with flood insurance has dropped significantly from its peak a decade ago. Economists warn that climate change could pose an even more severe risk to the housing market, and to the economy as a whole, than the recession of 2008.

Federal buyout programs play an important part of the country’s defenses against climate change, by giving homeowners in vulnerable places a way to relocate after a storm. That approach, sometimes called managed retreat, calls for pulling back from dangerous areas rather than continually rebuilding after each disaster, or pouring money into physical defenses such as sea walls and pumps.

But homeowners can’t apply for buyouts directly from the federal government. Instead, they rely on their local officials participating in those programs and deciding which homeowners can participate.

The paper found that while most buyouts take place in areas with high flood risk, that wasn’t the only factor at play. Many areas with equally high risk didn’t receive funding or received far less.

The data show that buyouts were disproportionately concentrated in wealthy and densely populated counties. The reason, according to the report’s authors, is that local officials must request federal funds for buyouts — and then successfully navigate a series of bureaucratic requirements — and wealthier jurisdictions are more likely to have the staff and expertise necessary to do that.

“Buyouts require resources and capacity to administer,” said Caroline Kraan, another of the study’s authors. “Not all governments may be equally able to access the program.”

In addition, once local officials receive the federal funds, buyouts aren’t evenly distributed within those counties nor are they distributed according to risk levels alone. Instead, counties tend to use the money to buy and tear down homes in poorer neighborhoods, the authors found.

There are different possible explanations for that, according to A.R. Siders, a professor at the University of Delaware and one of the paper’s authors.

Officials might feel that the poorer neighborhoods are genuinely the most vulnerable, Siders said. Those officials might also conclude that a given amount of federal dollars can go further purchasing a greater number of low-value homes, rather than buying just a handful of more expensive beachfront properties for the same amount.

Another explanation, she said, could be that local officials “are using the buyouts as an opportunity to get rid of neighborhoods that they don't feel are desirable parts of their community,” Siders said.

The research, however, wasn’t designed to examine which of those motivations was most prevalent. “All of these things are probably occurring,” she added.

David Maurstad, FEMA’s deputy associate administrator for insurance and mitigation, said the agency’s grant programs “are not designed to discriminate or address economic inequalities.”

“FEMA does not choose which properties participate in buyouts,” Maurstad said in a statement. “FEMA’s grant programs are designed to capitalize on the in-depth knowledge that each county floodplain manager and local official has regarding the needs of their communities.”

The new research is not the first to raise questions about the fairness or efficiency of FEMA’s buyout programs. Last month, the Natural Resources Defense Council, an environmental research and advocacy group, published a paper showing that it takes an average of more than five years between the time a flood strikes and when FEMA completes a buyout project.

As a result, many people give up waiting for the money and rebuild instead.

The reason buyouts take so long is that they require coordinated action by federal, state and local officials, as well as homeowners, according to Rob Moore, a senior policy analyst at NRDC and one of the authors of last month’s paper. A delay at any one of those stages compounds the wait.

“You could design a more cumbersome, complex process for buyouts,” Moore said. “But you’d have to think really hard.”

Still, the data also offers reason for optimism, according to Siders. “No matter how difficult managed retreat sounds,” she said, “we know that there are a thousand communities in the United States, all over the country, who have made it work.”

This article originally appeared in

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