Engineers and Surfside, Florida, officials are concerned that recent construction at a neighboring residential building may have contributed to instability at the Champlain Tower South building that collapsed last week -- and could potentially have been "the straw that broke the camel's back," according to one expert.
"Construction of a neighboring building can certainly impact the conditions, particularly the foundation for an existing building," Ben Schafer, a structural engineer at Johns Hopkins University, told ABC News. "A critical flaw or damage must have already existed in the Champlain towers, but neighboring new construction could be the 'straw that broke the camel's back' in terms of a precipitating event."
Construction at Eighty-Seven Park, a ritzy condominium that abuts Champlain Tower South to the south, began in 2015, when a firm called Terra Developers began erecting the 18-story building, according to news reports at the time.
The project caused such a ruckus for Champlain Tower residents that, in January 2019, a member of the board reached out to Surfside officials, according to records released by the city.
"We are concerned that construction next to Surfside is too close," Mara Chouela, a member of the Champlain Tower South board of directors, wrote to city officials. "The Terra project ... are digging too close to our property and we have concerns regarding the structure of our building."
Chouela received a terse response from Ross Prieto, the city's then-building inspector: "There is nothing for me to check."
"The best course of action is to have someone monitor the fence, pool and adjacent areas for damage," Prieto wrote, "or hire a consultant to monitor those areas as they are closest to the construction."
Champlain Tower South residents and condo board members continued to complain about the construction next door, mostly regarding Styrofoam and dirt from the construction site washing up into the Champlain pool deck and plaza.
On Tuesday, Surfside Commissioner Eliana Salzhauer slammed Prieto's response to Chouela, telling ABC News that it reflects "laziness" from a person "too comfortable" in his job.
"The residents should have a place to go for their complaints ... they should have been treated seriously," Salzhauer said. "What happened here is a wake-up call for every small town and for every government."
Prieto has not responded to multiple requests for comment.
A spokesperson for 8701 Collins Development LLC, a joint venture that was established by Terra and other developers involved in the Eighty-Seven Park project, told ABC News in a statement Wednesday that they are "confident that the construction of 87 Park did not cause or contribute to the collapse that took place in Surfside on June 24, 2021."
Joel Figueroa-Vallines, an Orlando-based forensic structural engineer, told ABC News that because Eighty-Seven Park is "lower in elevation" than Champlain Tower South, there is a possibility that the construction of the building could be a concern -- but that more evidence is needed.
"It's most important and necessary to not discard anything so early on that could potentially be a consideration," Figueroa, president of the engineering firm SEP Engineers, said.
Dr. Mehrdad Sasani, a professor at the Department of Civil and Environmental Engineering of Northeastern University, told ABC News that the method in which Champlain South's support structure was built would usually allow it to withstand disturbances to the soil near the surface, which means the impact of the excavation for the neighboring construction would have likely been what Sasani called "minute."
"But indirectly, as a result of a failure in the pool area and the deck slab, the parking garage roof could have been affected," Sasani said.
He said more information on both buildings, including a geotechnical distance analysis, would be needed to determine the potential role of the construction on the Champlain Tower. ABC News has requested relevant documents to the City of Miami Beach.
Dr. Mehrooz Zamanzadeh, a corrosion engineering expert, told ABC News that cracks and spalling on the Champlain building should also be examined to determine whether vibrations from the construction had any effect on the building's structural integrity.
Regardless, said Zamanzadeh, the building's accelerated deterioration and corrosion was likely a critical factor in the collapse. He said that corrosion inspections should be mandatory, and also called for building recertifications to be the performed more frequently than the current 40-year cycle.
Miami Dade County Commissioner Jose Diaz told ABC News that he would not speculate what role neighboring construction had on the collapse, but said, "We're going to investigate."