Surfside to talk stricter regulations after study found dozens of coastal buildings sinking
Surfside town commissioners plan to discuss how to better regulate development of new projects to protect nearby buildings after a study found 35 high-rises along Miami’s barrier islands are sinking beyond what would typically be expected.
In Surfside, the University of Miami study found subsidence — the sinking of land or a building — affecting 10 luxury high-rises, condos and hotels, including the Surf Club towers, the Fendi Chateau Residences and the Carlisle on the Ocean, and noted that nearby construction projects may have “accelerated, if not instigated,” the subsidence. Buildings in Sunny Isles Beach, Miami Beach and Bal Harbour were also affected, the study found.
Together, those high rises accommodate tens of thousands of residents and tourists. Some have more than 300 units, including penthouses that cost millions of dollars.
Though there are no immediate concerns about the integrity of the buildings, there are questions about whether there might be potential long-term impacts to real estate worth billions of dollars. Tina Paul, the vice mayor of Surfside, told the Herald ahead of a January 14 commission meeting that the study is the latest evidence pointing to a “definite need to have more oversight and accountability for new construction projects.” Surfside is the first town to put a discussion over the study on its official agenda.
One potential reason for the unexpected extent of sinking identified in the study are vibrations from construction of new adjacent buildings, as high-rises stand on pilings that are often driven 100 to 200 feet into the ground. Because South Florida is built on layers of sand and porous limestone, the authors reasoned that these vibrations could have compressed or rearranged sand – much like shaking ground coffee in a tin creates more space.
Engineers and developers say requirements to inspect the condition of neighboring buildings before any construction can start already are strict. But Paul, for one, says that “developers regulate themselves” and that she wants to further strengthen an ordinance she introduced to regulate seismic monitoring of new constructions and the effects they can have on neighboring properties.
The town agenda includes a discussion of the UM study but doesn’t detail what additional oversight of projects commissioners might consider.
Some sinking of large buildings is typically expected after construction as the weight of the structures compacts the ground underneath, experts say. And subsidence alone isn’t necessarily a concern. It was previously ruled out as the cause of the 2021 collapse of the Champlain Towers that killed 98 people in Surfside — a tragedy that heightened public, political and research attention to both the state’s aging condos and development overall on barrier islands.
The UM study was begun in the wake of that collapse. Satellite data cited in the peer-reviewed study that was published in a science journal in December showed that the process didn’t always slow down or stop as expected. Instead, imagery showed that some buildings continued to sink at 0.8 to 3 inches between 2016 and 2023.
The study’s authors and other experts have named several factors that are most likely at play: Pumping of groundwater from construction sites, changes in tidal flows and rising sea levels could also be a factor, experts said, as could stormwater that is supposed to drain into an already saturated underground.
Beyond strengthening the ordinance on new construction, Paul said that the issue of subsidence was “something that needs to be discussed, really on the county level and on the state level, because we should all be aligned with how we want to move forward.”
“I think it’s the elephant in the room that people don’t want to address,” she said. Surfside’s mayor, Charles Burkett, declined several requests for comment.
The UM study got a lot of initial attention from beachside communities, political leaders as well as real estate agents and developers, the latter two groups largely questioned the study, which was co-authored by 12 scientists from different universities in the US and Europe and later peer-reviewed.
But Paul isn’t the only official saying it raises questions that need clearer answers. Last month, the issue of subsidence was discussed at a meeting of building officials from across the county, a Miami-Dade County spokesperson said. Although there was no record of the discussion, the spokesperson told the Herald that “further analysis is needed” to better understand why the buildings might be impacted. The county is already working on changing building codes so that new underground garages will withstand the effects of rising sea levels, the spokesperson said, and to codify vibration limits.
Experts have said that the study made it clear that something is going on underneath our feet – potentially tied to the effects of climate change, rising sea levels and an increase of stormwater.
The mayor of Sunny Isles Beach, Larisa Svechin, told the Herald last month that she was confident the city’s buildings were safe, and that the town would take another look “only because we can, and for the sake of making sure that our residents feel 110% safe.”
Svechin has not responded to repeated requests for comment since. Sunny Isles officials also declined to share updates on the inspections they said they were conducting, and no discussion of subsidence or the study have been placed on the agenda for a commission meeting this week. Any visible signs of subsidence, the town said, would be noted in the recertification process of aging buildings required under a 2022 state law passed by the Legislature in the wake of the Champlain Towers collapse.
Update: Surfside’s commission meeting was held on January 14. About 100 people attended, in part to discuss policing. The discussion on subsidence was deferred until the next commission meeting.
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This story was originally published January 14, 2025 at 5:30 AM.
