SURFSIDE, FLA. (WSVN) - Nearly four years after the tragic collapse of the Surfside Champlain Towers South, the National Institute of Standards and Technology has released a comprehensive update, pinpointing the structural failures they believe led to the disaster.

In a matter of minutes, 98 lives were lost on June 24, 2021. It was a day that sent shock waves through South Florida.

Why did Champlain Towers South collapse? It’s a question that has loomed over the heads of many for nearly four years. Now, a new preliminary report is narrowing down the possible causes of the catastrophic collapse.

Investigative lead Dr. Judith Mitrani-Reiser and co-lead Glenn Bell with NIST are handling the painstaking process of determining what went wrong.

“This has been a very, very challenging investigation,” said Mitrani-Reiser in the video report.

The duo have been studying countless pieces of information regarding the building’s integral structure, utilizing videos, models, satellite images and more.

The latest video report released on Monday focuses on the possible failures of slab-column connections in the pool deck, weakened columns in the tower, and failure of joints that connect the slabs in the columns.

Investigators determined that the collapse was likely not related to issues underneath the building, like settling, sinking or piling failure.

“There were widespread areas where the construction of Champlain Towers South failed to meet the requirements of the design documents and applicable codes and standards,” said Bell in the video report. “Moreover, heavy materials were added to the structure, and deterioration and signs of distress increased with time.”

In the preliminary report, Bell said these issues had existed for decades.

“These conditions existed from the time construction was complete, 40 years before the partial collapse,” said Bell.

The final report is expected to be released next year.

“We intend for our investigation of this failure to have a lasting impact, save future lives and ensure this never happens again,” said Mitrani-Reiser.

Several events are set to be held Tuesday at the Champlain Towers South collapse site to remember the 98 lives lost.

For more information on the NIST’s investigation into the Champlain Towers South collapse, click here.

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