Crews initially planned to deconstruct the unstable, unfinished garage that was being built for the Children’s Hospital of Philadelphia. But after consulting structural engineers, officials have decided to instead demolish it, according to media reports. Emergency crews also used specially trained dogs, robots and drones to search for workers who might have still been alive, but they have found nothing. 

Fire Commissioner Jeffrey Thompson told local reporters that crews deployed dogs trained to find human remains. "Both independent of one another, and they both hit independently,” Thompson said, “so we were confident what we were dealing with was no longer a rescue but a recovery." 

While the victims were not identified, Mayor Parker said they belonged to the Ironworkers Local 401. A person who answered the phone at Local 401 on April 10 said the union will issue a statement to the media on April 13. 

Permits were properly issued and inspections were up to date for the $32.27-million project, according to the mayor. Construction started on the seven-story, multi-level, 335,000-sq-ft parking garage in 2025. Built to replace a surface parking lot, the garage was planned to have up to 1,012 spaces and was expected to be completed this year, according to city documents. 

The mayor said the city will investigate the collapse, as will the U.S. Occupational Safety and Health Administration. A specific cause has not been identified at this time. In her press conference, Mayor Parker described a progressive collapse scenario that appeared to begin with a precast concrete segment on the top floor and propagated down all seven levels of the garage.

PreCast Services Inc., which reportedly was installing precast concrete floor and roof components on the project at the time, could not immediately be reached for comment but emailed the following statement to ENR on April 16 

"We are deeply heartbroken by the tragic loss of our three team members," a spokesperson for the firm said. "We are offering our continued support to the families, as well as our entire team as we all grapple with this tragedy.We are immensely grateful to the emergency workers, Ironworkers Local 401, city officials, Children’s Hospital of Philadelphia, and the community for all their incredible support during the response and recovery process. Their kindness, compassion and commitment were felt by all of us.Over our nearly 40-year history of installing prefabricated concrete from numerous manufacturers, our company’s commitment to our employees has been unwavering. As with any project, there are multiple construction partners involved, and it will be some time before the investigation is complete and findings are released. We will continue to work closely with the city, OSHA, our construction partners and other entities to find answers for the families. Our hearts are with them always."

HSC Builders & Construction Managers is construction manager on the project. The firm last ranked at No. 40 on the 2019 ENR MidAtlantic Top Contractors list, with $186.93 million in revenue.

"We make significant efforts each and every day to ensure safe and secure jobsites for our workers, subcontractors and the public in general," said the firm in a statement. "We have never experienced a collapse or failure in the company’s history. Our immediate mission is to do whatever we can to aid the deceased workers and their families."

The project engineer of record, structural engineer and architect have not been publicly confirmed in reporting and Philadelphia’s license and inspection system does contain this information. 

Design firm THA Consulting Inc. is listed in public documents but the firm’s role is unclear. A rendering of the project credited to design firm THA Consulting Inc. was published online by the Philadelphia Inquirer.

A THA spokesman referred questions to the city, which did not respond before ENR’s request for comment.

A rendering of the parking garage. Image courtesy Children's Hospital of Philadelphia.  

“Children's Hospital of Philadelphia is aware of a serious construction incident at our parking garage construction site on 3000 Grays Ferry Avenue in Philadelphia," it said in a statement. "We are prioritizing the safety of the construction workers at this time and working closely with the City of Philadelphia and our construction partners. We will share additional information as it becomes available.” The hospital could not be reached for more comment