The collapse of the condominium building in Surfside, Florida, may force what some say is a long overdue conversation about the hard realities of climate change that will transform one of the nation’s most vulnerable regions.
To be sure, no evidence has emerged so far to connect climate change to the middle-of-the-night collapse of the Champlain Towers on June 24, which buried residents in the rubble. Sea level has risen eight inches in South Florida since 1981, when the 12-story condo was built—not enough to be responsible for its collapse, says Hal Wanless, a University of Miami geologist and South Florida’s preeminent voice on sea-level rise.
The investigation so far is more focused on a confluence of events—including delays by the homeowners association in carrying out recommended repairs—and an environmental danger that’s been known for more than a century: the corrosive effects of salt water on coastal construction.
Photos of corroded rebar and rotted concrete in the condo basement have recently been released. A 2018 report of an engineering inspection of the building, posted on the City of Surfside’s website, documented “abundant cracking and spalling in various degrees” in concrete columns. Spalling is a term used to describe concrete degraded by crumbling or cracks.
But if the present building codes and the inspections they require failed to prevent this failure, how will residents of the oceanfront high-rises that dot the coast be protected in the coming decades—when at least two feet of sea-level rise could dramatically eat away the beaches where towers now stand, increase the magnitude of storm surges, and spread salt-water intrusion further inland, worsening its corrosive effects?
With the accelerated melting of ice sheets in Antarctica and Greenland in the next decade, Wanless thinks two feet of sea-level rise could occur sooner than current projections. NOAA’s intermediate high for 2070 is 40 inches.
“We could well be two or three feet by mid-century, and once we are talking about those numbers, we are talking about within a 30-year-mortgage cycle,” he says. “That will make the viability of every barrier island in the world questionable.”
A lost decade
Officials in Florida’s four southernmost counties organized a decade ago to address climate issues that the Republican-controlled legislature had ignored. (Legislators conceded in 2019 they had “lost a decade” by failing to address climate change.)
In South Florida, the mayors and other officials have taken steps to mitigate flooding, which already occurs regularly in low-lying areas during high tides, and to plan for future impacts. For example, they are phasing out more than 100,000 septic tanks that will be rendered inoperative by the rising water table.
But conversations about the magnitude of the change that’s coming and the limited options for adapting, most of which will cost billions of dollars, are difficult. The most recent project under consideration would be a six-mile seawall built along the edge of Biscayne Bay through downtown Miami. It would be 20 feet high in places and cost $6 billion, according to an Army Corps of Engineers conceptual design. The magnitude of the wall as well as the price tag have horrified more than a few Miamians.
Phil Stoddard, a biology professor at Florida International University in Miami who served as South Miami’s mayor for a decade, says the notion that solid ground in South Florida will give way to flooding seems incomprehensible to some today, especially in an area brightened by endlessly blue skies and fueled, at least pre-COVID, by a roaring economy.
“As long as humans have existed in recorded history, land hasn’t gone away, and people I know talk about land being here for future generations,” he says. “It’s hard for people to get their head around that land won’t be here. They can hear you say it, but they don’t have a mental construct for this kind of thing happening.”
Meanwhile, the building boom that has transformed downtown Miami and spurred lines of new condo towers along Miami Beach, many with units priced at $30 million, continues apace.
The investigations begin
In the days since the Surfside collapse, 18 bodies have been recovered and searchers continue to dig for 145 people who remain missing. The search had to be suspended for much of Thursday after concerns were raised that the rest of the complex appeared unstable and could collapse as well. Searchers resumed as Tropical Storm Elsa, on track to hit South Florida early next week, grew into a hurricane.
The collapse has already prompted multiple investigations, including probes by FEMA and the National Institute of Standards and Technology, which investigated the collapse of the World Trade Center towers in the 9/11 terrorist attack. Miami-Dade State Attorney Katherine Fernandez Rundle announced plans to convene a grand jury to probe the disaster. A similar investigation after Hurricane Andrew struck in 1992 led to significant state building code reforms related to wind loads.
Officials have also ordered immediate inspections of older buildings in Miami Beach and the city of Miami.
John Pistorino, the structural engineer who investigated the 1974 collapse of a building in downtown Miami that housed the Drug Enforcement Agency, has been retained to conduct an investigation of the condo collapse. That probe led to the requirement that buildings in Miami-Dade and Broward counties be inspected and recertified at age 40. The goal was to prevent another collapse. The Champlain Towers was 40 years old and in the early stages of recertification, though maintenance and repairs recommended in an 2018 engineering report had yet to begin.
Pistorino says the existing building code addresses salt water corrosion and the type of concrete used in pilings as building supports.
“These buildings have been built and designed with the hostile environment we have in mind,” he says. “But they still require maintenance and upkeep from the day they were built, whether they are in coastal areas or not.”
Other engineers and builders have echoed Pistorino, arguing that new buildings are constructed to withstand sea-level rise. Raul Schwerdt, who owns RAS Engineering in Miami, told the Miami Herald that Florida buildings should be able to withstand rising sea levels if they are built correctly. “If the foundation has deep piles that go 30 feet under the sea that should hold the building forever, no matter what happens—if a hurricane comes or the building is flooded.”
Pistorino says the collapse of the tower will likely result in enhanced building inspections and greater involvement by homeowner associations and condo owners’ boards to make sure maintenance and repairs are carried out.
The most obvious lesson to be drawn from the disaster, he says, is that “you don’t wait 40 years before you start looking for problems in your building.”
What resonance?
The disaster at the Champlain Towers is a rare event. Buildings don’t just fall down in the United States. Numerous Miamians have observed that this event has “struck a chord” around the world, drawing international media coverage as well as speculation about a host of factors ranging from the safety of high-rises to the viability of homeowner association oversight.
Stoddard is not so sure the effects of the disaster on public opinion, in Miami and beyond, will be long-lasting.
“Has it struck a chord or hit a nerve?” he asks. “A chord resonates and goes beyond itself. Hitting a nerve hurts for a while and you recover from it. This certainly hit a nerve. But has it also hit a chord? Is it going to make people think about the bigger questions?”
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Miami condo collapse highlights urgent need to adapt to rising seas - National Geographic
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