Officials Find Deadly 2021 Surfside Condo Collapse Likely Began From Pool Deck

Federal investigators have shared the preliminary results of their ongoing investigation into the deadly 2021 Champlain Towers South condo collapse in Surfside, Fla., which likely began in the building’s pool deck.

The partial collapse of Champlain Towers South determined that the collapse likely began from the pool deck, which began collapsing before the rest of the tower, the National Institute of Standards and Technology (NIST) said in a statement on Tuesday, Sept. 9. The collapse killed 98 people.

The agency said it used “large-scale structural testing and computer analyses” of video to determine that the collapse progressed from the pool deck through the tower, NBC News reports.

“It is more likely that the failure started in a pool deck slab-column connection,” the NIST said in a statement, adding that the findings also suggest “the building was in distress in the weeks before the collapse.”

The building fell at 1:22 a.m., when the vast majority of residents were asleep.

The points of collapse were concentrated in a portion of the pool deck and a street-level parking deck. The NIST said the parking deck “has been confirmed to have begun collapsing at least seven minutes before the tower.”

Water leaked from the ceiling of the garage in an area that had many cracks and repairs over the years, according to the NIST. The flow of water “dramatically increased” in the hours before the collapse.

Associate Lead Investigator Glenn Bell acknowledged during the meeting that this has been a difficult investigation since there were “pretty widespread problems with the building, both in design and construction,” ABC News reports.

“Our team has worked tirelessly to find the causes of this disaster and we are on the home stretch, but much of the very hard work of bringing about change is still in front of us,” Bell continued, per the outlet.

Martin Langesfeld, who lost several family members to the collapse, told ABC News, “Four years. 98 dead. Nearly $40 million tax dollars spent, and we still have no answers and no accountability. That should be the media headline.”

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Investigators initially had 12 hypotheses about what caused the deadly collapse, per The Miami Herald.

“The investigation has also identified indications of the building’s distress that were visible in the weeks before the partial collapse of the building in Surfside, Florida,” the NIST’s statement read.

The agency has been investigating the collapse for more than four years, and will officially conclude the inquiry at the end of 2025. Investigators first found early evidence pointing to the pool deck in 2024.

PEOPLE has reached out to the NIST for comment.