The Champlain Towers Miami condo tower collapse started the bottom of the building and the rest of the structure came down with it, experts who viewed footage of the collapse have claimed as relatives of people who went down with it say they told them they saw a 'hole' forming next to the swimming pool.
Officials won't yet comment on what exactly brought the 40-year-old tower down but experts who have viewed footage of it say it started with a problem in the bottom of the building - perhaps the parking garage - and once that crumbled, huge swathes of the building came down with it.
'It does appear to start either at or very near the bottom of the structure. It’s not like there’s a failure high and it pancaked down,' Donald O. Dusenberry, a consulting engineer who has viewed footage of the collapse, told The New York Times on Monday.
What the problem was in the lower part of the building is unclear but a 2018 report into the building found a 'major error' in the construction of the swimming pool where water didn't drain but just sat on the surface then evaporated.
The engineer - Frank Morabito - recommended $12million of repairs as a result and they were due to begin but hadn't yet.
One issue he highlighted was corroding reinforced steel which Dusenberry said could have contributed to the building coming down if it was exaggerated enough.
'If I were an investigator, I would check this as an issue,' he said.
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The bottom center of the building was the first to collapse at around 1.30am on Thursday morning. The bottom gave out and then the other parts of the building followed seconds later
The rear of the center column was second to collapse, just a few seconds after the front of it crumbled from the bottom
The eastern part of the tower was the last to fall, six seconds after the center began crumbling from the bottom
Workers search the rubble at the Champlain Towers South Condo, Monday, June 28, 2021, in Surfside, Fla. Many people were still unaccounted for after Thursday's fatal collapse
Workers search the rubble at the Champlain Towers South Condo, Monday, June 28, 2021, in Surfside, Florida. Rescue teams say they are confident they may still find people alive
People pray on the beach outside the Champlain Towers South debris on Monday morning as the search for survivors continued
Part of the building remains in tact but there are fears it may collapse or will have to be entirely torn down
MODEL SAW SINKHOLE FORM NEXT TO POOL SECONDS BEFORE COLLAPSE
Model Cassondra Billedeau-Stratton said in a phone call with her husband Mike Stratton that she had seen a sinkhole where their pool used to be before before the line cut out.
'It was 1.30am, I'll never, never forget that,' Mr Stratton, a 66-year-old Democratic political strategist, told The Miami Herald.
Model Cassondra Billedeau-Stratton said in a phone call with her husband Mike Stratton that she had seen a sinkhole where their pool used to be before before the line cut out
Billedeau-Stratton, 40, had felt sudden shaking from her fourth-floor balcony and called her husband screaming before saying that there was a sinkhole, reports the newspaper.
Mr Stratton, who was in Denver at the time of the call, told the Washington Post that she screamed that she had seen the pool deck cave in and 'then the phone went dead.'
'She screamed bloody murder and that was it,' Mr Stratton told Billedeau-Stratton's older sister Ashley Dean.
Ms Dean told the Washington Post that her sister 'knew something was wrong' in the says before the collapse as she had complained to her family about water damage in the building and heavy equipment being lifted to the roof for repairs.
She said it is hard to hold out hope for her sister to come back to her.
'I want to have hope,' she said, 'but I'm a realist. I don't want to hold on to false dreams.'
Billedeau-Stratton is among the 151 people who are missing after the 12-story condominium building in suburban Miami collapsed early Thursday morning. Ten deaths have been confirmed so far.
A structural engineer who inspected the Champlain Towers last year told CNN that the hole witnessed by Billedeau-Stratton 'definitely' could have been a factor in the sudden collapse.
Jason Borden said that if the pool deck or a structural slab near the building failed or had been compromised, 'it could have contributed to the end result'.
Seconds before the building collapsed, model Cassondra Billedeau-Stratton woke up to the building shaking.
She called her husband and told him she could see what looked like a sinkhole forming next to the pool. Moments later, the line went dead.
The developer who built the condo tower is no longer alive. The building was due to undergo repairs as part of its 40-year recertification process but the only work that had begun was on the roof. Structural, electrical and concrete updates were also required.
Surfside Mayor Charles Burkett said on Monday morning that the cause of the collapse was secondary to the rescue mission.
'There's been some discussion about why this happened, that's an issue for another day. Right now we have to pull our family and friends out of that rubble.'
'We will get to the bottom of it,' he said.
'We continue to work the pile, we have over 80 rescuers at a time that are beaching the walls in a frantic effort to rescue those that are still viable and to get to those voids that we know exist in these buildings.
'We have found voids within the building that we've been able to penetrate - mostly coming from underneath on what used to be the garage. We have been able to tunnel through the building.
'This is a frantic search to see that miracle, who we can bring out of that building alive. we are all holding out for that hope that we are going to be able to rescue somebody. The pile conditions are bad, obviously.
'During the day, we've got the sun and humidity... it rains. The conditions are not ideal but nonetheless we are working tirelessly to try to bring victims that are underneath that rubble, to rescue them.
'We have the latest technology in terms of equipment- underground sonar systems to detect victims, we brought in huge cranes to help us lift big slabs of concrete that we didn't have at the beginning, basically turning the big pieces of rock into smaller rocks to get them off the pile.
'We're doing big lifts, getting big pieces off of the pile and that's going to aide us to laminate this building almost like an onion so we can get inside and again find those voids that we know might possibly be there and rescue those people,' he said.
'I know the families ask why we are not going faster,' says Maggie Castro, a paramedic with the Miami-Dade county fire department.
In a strange way it is hope itself, even now, that is slowing them down, she explains.
'We have the potential for having void spaces, these pockets that can potentially be in the rubble where we can find live victims,' she tells AFP.
'If we just jump on these piles and attack, we will collapse these spaces.
'It seems slow but it's as fast as we can go.'
'Heavy machinery cut large pieces and remove the ones that are safe to be removed. When we come to an area where there would potentially be a void space, we work by hand, remove debris bucket by bucket until we get to the area we want to,' Castro, a 52-year-old rescue specialist who has been with the department for 17 years, says.
With listening devices and sniffer dogs they strain for any sound that could lead them to life.
'We hear falling debris, twisting metal,' Castro says. 'We have not heard human sounds.
One of the main people who was allegedly involved in the construction of the building in 1981 was developer Nathan Reiber, who faced legal troubles in the 1970s in Canada, before turning his attention to south Florida.
According to the Washington Post report, Reiber and his partners couldn't start construction of the now-collapsed tower because of 1979 moratorium, which was put in place because of faulty sewers in the area.
But they skirted around the moratorium and got their project approved by agreeing to pay half of the $400,000 tab for sewer repairs on the property.
An alarming report released by officials overnight Friday reveals an engineer warned about structural issues on the condo tower three years before it collapsed
The center portion of the tower was the first to fall with the east section of the building collapsing moments later
Workers search the rubble at the Champlain Towers South Condo, Monday, June 28, 2021, in Surfside, Florida, five days after the building collapsed
There are now hundreds of rescue teams at the site combing the rubble for survivors
Rescue workers uncover a Sterns and Fosters bed mattress at the Champlain Towers collapse on Monday morning
This angered other developers whose projects were stalled by the moratorium and led to accusations that Reiber and his team received preferential treatment, the Washington Post report reported.
Reiber, who died of cancer in 2014, demanded that the campaign donations be returned when allegations of their pay-to-play scheme surfaced.
Reiber's widow and two of his children did not return calls to the Washington Post.
In 2018, the building that Reiber and his team built had been flagged for 'major structural damage' to the pool deck area and underground parking garage in a damning report.
The tower was about to undergo a $15million renovation project to pass a required 40-year certification before it collapsed early Thursday. As of Monday morning, 10 people were dead and 151 were still missing.
A consultant engineer warned back in October 2018 that the Champlain Towers South building in Surfside, Miami Beach, was in need of numerous repairs around the base of the structure 'in a timely fashion.'
The structural field survey report specifically raised concerns about the pool deck area, in which the waterproofing was failing, and the underground parking garage which was riddled with 'abundant' cracking.
Two days after receiving the report, a Surfside official assured residents that Champlain Towers South building was in 'very good shape', CNN reported.
Despite the apparent urgency of some of the recommendations, an attorney for the resident-led condo association told the New York Times this week that repairs were only about to begin - more than two and a half years after the inspection.
In light of the tragedy, the City of Miami sent letters to condo associations of 40-plus-year-old buildings above six stories, urging them to get an inspection from a qualified structural engineer within the next 45 days and sent back a status report on the conditions, a city staffer told CNN.