An area of standing water beneath the Miami condo that collapsed was in the same place as a 'major' design flaw found in 2018, a new report says

• A pool contractor took photos of water damage beneath the Miami condo that collapsed last week.
• At least 11 people were killed in the collapse, with 150 others still missing.
• Standing water was found in the same area as a "major" design flaw identified in a 2018 inspection.

Shortly before the collapse of a Miami condominium last week, standing water was found in the same area as a "major error" identified in 2018 in the original design of the building, the Miami Herald reported Monday.

Eleven people are confirmed dead after Champlain Towers South partially collapsed early Thursday, with 150 people still missing.

It's still not clear what caused the collapse, but experts say a structural failure at the bottom of the building could be to blame.

A pool contractor who visited the building just two days before the collapse took photos of damage in the garage, showing cracks in concrete and wet floors in the pool equipment room.

The contractor, who remained anonymous, told the Herald he thought the amount of water at Champlain Towers was unusual. A staff member who was showing him around told the contractor that he "thought it was waterproofing issues," according to the Herald report.

"I thought to myself, that's not normal," the contractor told the Herald, adding that the staff member did not mention any structural damage in the building caused by the water.

The deepest area of standing water in the building was said to be located near parking spot 78 in the garage, which was directly under the condominium's pool deck. The Herald reported Sunday that a 2018 inspection report flagged a flaw in the building's original design, with a lack of proper drainage on the pool deck causing "major structural damage."

Mohammad Ehsani, an engineer and concrete-restoration expert, reviewed the photos obtained by the Herald and told the newspaper it was the worst damage documented in a building that he had seen.

"You can see extensive corrosion of the rebars at the bottom of the beam. That is very serious," Ehsani told the Herald, saying the condition of the beam was a "really major concern."

Ehsani warned against rushing to the conclusion that the corroded beams were the cause of the collapse, though he said the damage captured in the contractor's photos should have prompted alarm.

"In these buildings that are asymmetrical like this one, there is a possibility that if you have one part of the building that collapses, the building does some turning and twisting," Ehsani told the Herald. "In this case, it is possible that a failure any place in this building could cause distortion to the frame of the building and could cause a collapse in any of the areas, not just adjacent [to the failure]."