Insurance Daily News

Miami Beach Skyscrapers Sinking Due to Construction

A recent study published in the peer-reviewed journal Earth and Space Science has identified a concerning trend in Miami Beach: the city's skyline is sinking, with specific structures settling at uneven rates. Led by researchers from Florida and German universities, including Farzaneh Aziz Zanjani and Falk Amelung from the University of Miami, the research utilized satellite-based Interferometric Synthetic Aperture Radar (InSAR) to monitor the elevation of 35 buildings over the last decade.

The data collected between 2016 and 2023 indicates that while some buildings have subsided by approximately 2 centimeters, others in Surfside and Sunny Isles Beach have dropped by more than 8 centimeters. The study attributes this subsidence to load-induced, prolonged creep deformation within the underlying limestone and sandy layers. Crucially, the researchers concluded that this process is being accelerated, or potentially triggered, by ongoing construction activities on the barrier island.

Among the structures highlighted in the study are the 60-story Porsche Design Tower, which has faced resident complaints regarding leaks and cracks, and Trump Tower III, which is settling at a rate of nearly one centimeter annually. While some initial settling is common for large skyscrapers following construction, the study suggests that the current subsidence in Miami Beach is not stabilizing. Instead, the researchers warn that vibrations from nearby construction projects may be restarting grain rearrangement processes, leading to renewed acceleration of the sinking.

Context: This research provides a critical data point for the insurance and real estate sectors. Differential subsidence—where parts of a building or adjacent structures settle at different speeds—can lead to significant structural integrity issues, potentially increasing the frequency of insurance claims and the complexity of risk assessment. For structural engineers and municipal planners, this highlights the need for more granular monitoring of ground stability in high-density, low-elevation coastal zones.

The study also addressed the 2021 collapse of Champlain Towers South, noting that the building showed no signs of subsidence prior to the disaster, which was largely attributed to deteriorated support columns. However, the researchers observed that the 87 Park tower, located adjacent to the former Champlain site, is currently exhibiting signs of sinking. Furthermore, the study noted that even low-rise buildings with lighter structural loads are showing subsidence, which the authors conclude is almost certainly linked to construction activity.

While city officials in Sunny Isles Beach previously stated they had received no reports of damage linked to settling, the study's authors remain cautious. They found no evidence that the subsidence will cease, suggesting that as long as construction continues to disrupt the sandy layers within the limestone, the ground beneath these iconic structures will remain in flux. Management for the buildings cited in the study declined to comment when contacted by the Miami Herald.

Why it matters

The findings suggest that ongoing construction in Miami Beach is destabilizing the ground beneath major skyscrapers, creating long-term structural risks that insurers and municipal planners must now account for.

FAQ

What technology was used to measure the sinking of the buildings?
The researchers used satellite-based Interferometric Synthetic Aperture Radar, commonly referred to as InSAR.

What is the primary cause of the subsidence according to the study?
The study attributes the sinking to load-induced creep deformation of sandy layers within the limestone, which is exacerbated or triggered by construction activities.

Did the study link the sinking to the Champlain Towers South collapse?
No, the study noted that Champlain Towers South showed no signs of subsidence before its collapse, which was blamed on deteriorated support columns.

Source: Insurance Journal. See the original source for full details.