SURFSIDE, Fla. — The Champlain Towers South had “major structural damage” to a concrete structural slab below its pool deck, according to a 2018 engineering report on the building.

The report was released Friday night by the town of Surfside as rescuers continued to search for possible survivors in the rubble of the collapsed building.

Miami-Dade Mayor Daniella Levine Cava reported no change in the number of people still unaccounted for, 159 or the death toll, 4. “We are at status quo,” she said. “I’m hopeful this will be a day that we have will have a breakthrough.”

The engineering report about the pool deck and recommended repairs was issued from the firm of Morabito Consultants. However, the report did not warn of any “imminent danger” from the damage. In addition, it is unclear if pool deck spalling was responsible for the collapse early Thursday morning. The report did recommend that the damaged slabs be replaced but the extensive and costly repairs were not made as of June 2021. Also, the building just underwent its 40 year certification and the structural inspector reportedly flagged “no grave problems.

This despite th 2018 report that said the “waterproofing under the pool deck had failed and had been improperly laid flat instead of sloped, preventing water from draining off.”

“The failed waterproofing is causing major structural damage to the concrete structural slab below these areas. Failure to replaced the waterproofing in the near future will cause the extent of the concrete deterioration to expand exponentially,” the report said.

The report also uncovered “abundant cracking and spalling” of concrete columns, beams and walls in the parking garage. Some of the damage was minor, while other columns had exposed and deteriorating rebar. It also noted that many of the building’s previous attempts to fix the columns and other damage with epoxy were marred by poor workmanship and were failing.

Beneath the pool deck “where the slab had been epoxy-injected, new cracks were radiating from the originally repaired cracks,” the report said.

Engineers noted design flaws and failing waterproofing that would lead to “exponential damage” about 990 days before much of the Champlain Towers South condominium complex collapsed, documents released late Friday night show. The town of Surfside, Fla., released the documents including an “unverified” 40-year inspection report that had been received 16 hours after the building’s catastrophic failure.

A letter to the condomimum association’s treasurer on Oct. 8, 2018, included pages of recommended repairs.

A document dated April 26, 2021, titled “40 year building repair and restoration,” includes 84 pages of what appear to be bid specifications for repair to the building. The plans were completed by Morabito Consultants and stamped in red with “in progress set 4/27/2021, not for construction.”

A sister building also built in 1981 near the Champlain Towers South by the same developer located near the collapsed building is being inspected and may have to be evacuated.

Saturday morning, rescuers combed the debris pile with machinery, drones, microphones and their own hands hopefully unearth one of the still 159 unaccounted for residents of the 12-story Champlain Towers South.