How sea rise could reshape South Florida neighborhoods: Retreat here, growth there

As sea levels push ever higher, the question of when — and where — it will affect South Florida’s real estate market is a big one.

Research suggests people aren’t interested in paying a lot of money for a home that floods, and the number of properties at risk of flooding is only expected to rise in the coming decades. For an economy that relies on a booming real estate market to function, predicting which spots could lose value and when is crucial.

A study published Monday in the journal Nature Communications takes a stab at the question that looms over South Florida’s future. It found that, while population will likely continue to grow overall in Miami-Dade and Broward County this century — dozens of neighborhoods prone to flooding now could see people move out, permanently.

And that could happen soon. The research found frequently flooded spots in Miami-Dade could see resident flight as soon as 2028. In Broward, it could happen around 2032.

The study suggests that high-elevation areas will grow the most, both from new arrivals and from moves within the county. And some spots, like Miami Beach and Fort Lauderdale, could see more people leaving than arriving as flooding becomes more common. The research is based on a model of current flooding, projected into the future, combined with projections of future population change.

Researchers say that more common flooding will make insurance more expensive and mortgages harder to get, and fewer people will want to deal with the annoyance of flooded streets or the expense of flooded homes, leading to a retreat from these areas.

READ MORE: New study warns of ‘climate insurance bubble.’ Is that driving costs up in Florida?

But that projection clashes with current reality, where Florida is one of the fastest growing places in the nation, including flood-prone areas, and waterfront real estate values continue to soar. And another recent study found that many residents in Miami-Dade say that, despite the flood issues, they plan to stay here forever.

Jeremy Porter, co-author of the study and head of climate implications at First Street Foundation, a nonprofit climate research group, said the data suggests that Florida’s coastal growth is already affected by rising flood risk, and that without it, even more people would be moving to the Sunshine State.

“They’re growing, but just not as much as they would have without the flood risk. From an outsider’s perspective, that effect would be hidden. You’d say our population is growing,” he said. “If we project out a hundred years, then you start to see places in Florida and the South starting to reverse their trends.”

Researchers also produced maps of where they estimate populations will rise (in red) and fall (in blue) due to flooding issues in Broward and Miami-Dade. Generally, places that already have flooding issues now show up as blue zones, while more inland, high-elevation spots are growth areas.

Are people moving because of flooding?

The paper is the latest in a growing body of research that says Florida’s real estate market is in for big impacts as rising sea levels make flooding more common, driving down property values, making insurance pricier and mortgages harder to get.

But while the academic research suggests that it could already be happening on a small scale, like the studies that found Miami-Dade County homeowners are starting to pay more for houses on high ground than low ground, it’s still unclear what — if anything — could tip South Florida’s real estate market from its continued boom to a bust.

READ MORE: ‘Now, it’s about elevation’: Buying a South Florida home in the era of sea level rise

Mathew Hauer, co-author of the paper and an associate professor of sociology at Florida State University, said he believes the biggest factor will be information.

In Florida, homeowners and landlords are not required to disclose if their property floods, and there’s no single database where people can see which parts of their community flood, both because that information isn’t well documented and because sharing it publicly could threaten real estate values, a big no-no in Florida.

“People just don’t know. I think people understand in a global sense, sea level rise, climate change, Miami’s threatened, that kind of thing, but I don’t think that people understand on a local level,” Hauer said. “It’s still not quite widespread enough to move larger markets yet.”

Some newer research backs up Hauer’s theory. A study from Redfin last year found that when people had access to data showing the flood or fire risk of a home, they were more likely to end up bidding on a home with less flood and fire risk.

However, other studies show that some of the most dangerous spots in Florida are filling up with more and more people, even after a hurricane swipe. And despite the enormous safety gains realized by far safer building codes, overall, more people are at risk than ever before, simply because people keep moving to unsafe places.

READ MORE:‘On borrowed time.’ Why coastal Florida keeps rebuilding after storms like Hurricane Ian

Further complicating the future picture is that the projections in this paper — and others — are based on a world where nothing is done to slow climate change or sea level rise, which is not the case in South Florida. Building codes are elevating new construction and local governments are investing hundreds of millions of dollars to raise roads and beef up stormwater pumps and pipes.

So the question of what Florida’s coastal neighborhoods will look like is more complicated than any one study can predict. It depends on how fast and how well Florida adapts to rising seas and how comfortable people are willing to get with flooded streets and driveways before they want to make a change.

“That’s one of the big open questions — what is the actual tipping point?” Hauer said. “The weaselly answer is it’s different for everyone. What is the average person’s response rate? How much are they willing to take? We don’t know.”

What residents say

So far, most of the research exploring the question of what retreat from sea level rise might look like in South Florida has been done with maps and models. But when directly asked about their future plans, many Miami-Dade residents had a different answer than the climate models suggest.

In deep interviews with 40 South Florida residents and shorter surveys of 600 more, researchers published in the journal Climate Risk Management found that flooding already shapes the lives of plenty of residents. More than a third said they’d missed work or school due to flooded roads, several had lost their cars and a couple described incidents where intense flooding had physically trapped elderly relatives inside their home, out of reach from an ambulance in case of an emergency.

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And yet, despite the increasing risk of flooding, the majority of respondents told Nadia Seeteram, co-author of the study and a post-doctoral research student at Columbia University, that they wanted to live in Miami-Dade for the rest of their lives. And even among those who said they wanted to leave, the vast majority wanted to stay in Florida, often moving only a county or two away.

“It’s clear that people really want to stay in Miami. They really want to adapt in place,” she said.

Very few people said flooding prompted the desire to relocate. And for the handful that said sea level rise or flooding was a top concern, it was always coupled with something else.

Like the woman in Opa-locka who said she was so fed up with the rainfall-driven flooding in her neighborhood that she planned to move to Florida’s west coast. There, she said, she could also afford to purchase a home for the first time.

“It was just never the only reason. It’s always ‘climate and’,” Seeteram said. “That still has the power to reshape these neighborhoods or move people away from these high-risk areas.”

But that reshuffling might be still a ways away. The team also heard stories from residents who were fully aware of the risk they faced and didn’t care at all, like a woman who recently bought a condominium in Key Biscayne.

“She knew the risks. She just wanted to live on the beach and really hoped she could offload that risk onto somebody in 5 years or so,” Seeteram said. “She probably could offload it in the next 5 years and probably make some money.”

With the real estate market continuing to expand, even in the riskier spots in South Florida, Seeteram said it remains to be seen when — or if — buyers and sellers will start to factor in sea rise flooding into their decision-making.

“I mean, It hasn’t collapsed yet.”