Officials in Miami-Dade County, where climate models predict two or more feet of sea level rise by 2060, have released an optimistic strategy for living with more water, one focused on raising houses and roads, denser construction further inland, and creating more free space for flooding in lower areas.
The plan, released on Friday, described rising seas as mostly manageable, especially for a low-lying area with a century of experience in water management.
Climate experts, however, have warned that the county’s plan downplays the scale of the threat, saying it failed to warn residents and developers of the risk of continuing to build near the coast in a county whose the economy relies heavily on waterfront real estate.
“I’m not sure it really matches the challenges Miami will face,” said Rob Moore, senior policy analyst at the Natural Resources Defense Council. He described the strategy as “just enough to reassure developers that Miami is safe enough to integrate, in the short term.”
The Miami-Dade debate is part of a larger fight over how to respond to the growing threat of climate change nationwide. As floods, wildfires and other dangers worsen, disaster experts have increasingly urged local authorities to reduce their exposure by encouraging people to leave vulnerable areas. But cities and counties often resist this advice, fearing that a withdrawal will hurt their economies and upset voters.
This debate has been particularly intense in South Florida, which faces serious threats from climate change. In the Florida Keys, just south of Miami-Dade, officials recently said it was not economically possible to protect every home from rising sea levels because the small population did not provide enough water. tax revenue to pay for projects.
What is happening in Miami will most likely become a case study for other cities and counties facing climate challenges. Among the large metropolitan areas in the United States, it is perhaps the most prone to sea level rise, due to its flat, low geography. And, with some of the most expensive coastal real estate in the world, it has a large tax base to experiment with solutions – and also huge economic incentives to deter buyers and investors from leaving.
Local officials say doing nothing is untenable. By 2040, more than $ 3 billion in assets could be lost to daily flooding without action to reduce the threat, according to a report released last fall by the Urban Land Institute. By 2070, that figure is expected to rise to $ 23.5 billion. But Katherine Hagemann, who heads climate adaptation policy for Miami-Dade, said it didn’t make financial sense to respond to these threats by pulling off the coast or paying large numbers of people to leave their homes. It made more sense, she said, to try and keep those areas habitable.
“You are now seeing a very high return on investment for adaptation, to protect the macroeconomic situation in South Florida,” Ms. Hagemann said. “The cost of retirement in some of these places, if you were to buy them back at market value, would be really high.”
The county’s strategy focuses on a series of actions, noting that each has drawbacks.
These include raising houses on stilts, which allows water to pass underneath during flooding. This approach may work well when building new homes, but it is expensive for existing structures. And that does not prevent the roads that lead to the houses from becoming impassable.
Another way to raise houses and roads is to repeatedly haul earth and rocks from elsewhere, using it to raise the level of the ground itself when building or rebuilding houses. This approach, called backfill, can simply push water onto neighboring plots. And, as the master plan notes, it “can be technically and financially difficult to raise an embankment property multiple times.”
The strategy also calls for the construction of denser housing on higher land far from the ocean. But these areas – which until recently were less in demand than coastal properties, but are now garnering more interest – are home to many of the county’s low-income families and people of color, and the document warns they could be evicted. of their territory. houses by rising costs, a phenomenon some call “climate gentrification.”
Yoca Arditi-Rocha, executive director of the CLEO Institute, a Florida nonprofit that advocates for action to protect communities from climate change, praised the county for recognizing that the strategy could increase the risk of displacement of people. low income residents. “The rich and poor in Miami-Dade County face different types of risks from rising sea levels,” she said via email.
The answer is to build more homes for low-income residents, said Zelalem Adefris, vice president of policy and advocacy at Catalyst Miami, which works with low-income communities in the county. She urged officials to focus not only on adapting to climate change, but also on reducing greenhouse gas emissions.
“We’re not going to want to flirt and fill forever,” Ms. Adefris said.
Mike Hernández, a Democratic political consultant who worked in communications for the former county mayor, said the fundamental challenge was that elected officials were reluctant to recognize the seriousness of the threat. He called the county’s new strategy a “best case scenario”.
“When you talk about adaptation, people will say, ‘OK, we’ll build around that,’” he said. “But what adaptation really means – and that’s the scary part, I think, for many elected officials and administrators – is adaptation can mean ceding land. It could mean pushing people inland or putting up a barrier. “
“Unfortunately, it won’t be pretty,” Hernández said.