Surfside and climate change: a warning of Miami's future?

Surfside and climate change: a warning of Miami's future?

Early in the morning on June 24, 2021, the twelve-story Champlain Towers South condominium in Surfside, Florida, just north of Miami Beach, underwent a partial collapse that brought down roughly half of the building. As of this writing in the evening of July 1, eighteen people are confirmed dead and eleven more injured, numbers that are likely to rise as the search for survivors continues given that 145 people are missing.

Amidst all of the debate about the causes of the collapse, from lackadaisical inspections to incompetence and corner-cutting in the building’s board of directors to the repeal of regulations, a specter that haunts Florida has reemerged here. Climate change has long been understood by scientists and engineers as a potential game-changer for South Florida in the worst possible way, one that threatens the literal and figurative foundations of the city’s prosperity by increasing the risk of flooding in large, built-up areas even during normal weather conditions, as seen annually during the city’s “king tides” that have forced Miami Beach to invest in pumps to remove water from the streets on sunny days, as well as exacerbating the area's preexisting environmental problems. Like many natural disasters in recent years, this one by itself has many causes, not all of them related to the climate, with human negligence being particularly critical here. However, the evidence suggests that environmental damage in South Florida was a force multiplier that exacerbated the building’s mounting structural issues, raising the possibility that the Surfside collapse will not be the first, but will merely be the start of a long pattern.

It has been known for a while that the ground underneath South Florida is sinking. Even taking sea level rise out of the equation, ground-level elevations have been dropping across the region, in a process attributable largely to overuse of groundwater. In other parts of South Florida, saltwater intrusion caused by the over-extraction of groundwater has forced towns to abandon their freshwater wells and start importing tap water from elsewhere in the state. Another consequence of over-extraction, seen in New Orleans and other parts of the country where groundwater has been heavily pumped, is subsidence, in which the soil compacts as the water within it is pumped out. In some areas, the ground can subside to a point below sea level. Buildings constructed in previous eras were not built to account for this, and in some parts of South Florida, critical infrastructure is falling below sea level. A 2020 report noted that the town of Surfside had been undergoing subsidence since the early '90s, and that the area around the Champlain Towers was especially bad, sinking at a rate of about two millimeters per year. Accounts from engineers who worked on the Champlain Towers and warned that it was crumbling noted that rebar around the base of the building was exposed and rusting, a telltale sign of exposure to saltwater. The building's manager expressed similar concerns in the late '90s. Two millimeters a year may not seem like much, but it adds up over time, and in coastal ecology, the difference between ecosystems can come down to inches.

The famed beaches of South Florida have also long been vulnerable to similar pressures. Beach erosion is a process that, for decades, coastal communities have taken to fighting through various means, from engineering solutions like seawalls, groynes, and other "hard" controls to beach nourishment, which involves the literal replacement of lost sand. It is a natural process, as the coastal water cycle constantly reshapes beaches and sandbars, but it is one that humans have exacerbated through coastal mismanagement, and it is an inconvenient one for communities built on beaches that depend on them for tourist revenue. Beach erosion, of course, is an issue that climate change exacerbates, as rising water levels mean that more sand further inland gets washed away. By bringing the ocean closer to the Champlain Towers, beach erosion may have made it easier for seawater to attack the building's vulnerable foundation.

Taken together, these issues present a dark omen for South Florida. A great many coastal buildings, especially older ones built amidst the cocaine-fueled excess of the '80s, may appear to stand tall and firm today, but their foundations may not be much deeper than literal sand. As seas rise, the ground sinks, and beaches are washed away, decades of environmental mismanagement puts one of America's largest urban economies, one that was already extremely vulnerable, in grave danger, with Champlain Towers South serving as an example of what may await.