A study that detected vulnerabilities in high-rise blocks north of Miami Beach, where a condo building collapsed on Thursday morning, found numerous other parts of the city were sinking at faster rates at that time.
A section of Champlain Towers, located at 8777 Collins Avenue in Surfside, Florida, collapsed at about 1 a.m. on Thursday, killing at least four people. The search is continuing for survivors, and the number of people unaccounted for is at least 159, according to Florida Miami-Dade County Mayor Daniella Levine Cava.
In a study published in 2020 focusing on the sinking of buildings in Miami and the coastal town of Norfolk in Virginia, Shimon Wdowinski, a professor at the Department of Earth and Environment at the Florida International University, found that the condo building had been sinking since the 1990s.
He told the publication that after the building collapsed, he remembered the site from his report and looked back at it and said: "'Oh my god.' We did detect that."
He explained that his research isn't supposed to predict where a building will collapse, but said that it highlights areas in Miami that could be vulnerable to sinking after being hit with repeated coastal flooding.
The study, parts of which are shown in a video with Wdowinski on the Florida International University website, used blue dots across Miami to show high levels of coastal flooding and red lines highlighting roads that were vulnerable.
It looked at areas of Miami from 1992 to 1999 using Interferometric Synthetic Aperture Radar technology to compile datasets of the levels of sinking in different parts of the city.
The study revealed that there has been significant flooding in the southwest area of South Beach and found parts of northeast Miami Beach where the ground sank over the time period studied.
The ground also sank in an area surrounding Park View Island where an elementary school is located, doing so at a rate of 2.33 millimeters between 1992 and 1999, according to The Daily Mail.
The island of North Bay Village was also found to be sinking in the study, while the Lummus area of South Beach was identified as sinking at 2.2 millimeters a year.
All of those areas were sinking at greater levels than Champlain Towers at the time of the study, which sank by around 2 millimetres a year between 1993 and 1999.
However, Wdowinski said that although this could have affected the building's structure, it wouldn't have led to the collapse unless the sinking sped up in the decades following the study.
In the video on Thursday, Wdowinski said that the level of subsidence was "pretty small," but explained that "when you think about the accumulation over time then it can be a few inches over decades and that was our concern."
Newsweek has contacted Wdowinski for comment.
