NTSB blames Pittsburgh, PennDOT and inspectors for Fern Hollow Bridge collapse
PITTSBURGH (KDKA) — The city of Pittsburgh's failure to act on repeated maintenance and repair recommendations from inspectors led to the collapse of the Fern Hollow Bridge, the National Transportation and Safety Board said in its final report issued on Friday.
The report determines the probable cause of the bridge's collapse on Jan. 28 was corrosion and section loss that led to the failure of the transverse tie plate on the southwest leg.
The reason it failed is multifaceted. Completely clogged drains forced water to run down the bridge's legs and that caused the water to puddle at the bottom, corroding and deteriorating the support. The report said the bridge then gathered debris, which prevented the development of a much-needed protective rust layer.
The city failed to act on recommendations documented in inspection reports from 2005 to 2021, leading to progressive deterioration and structural failure, the report says.
The NTSB also blames the Pennsylvania Department of Transportation for the collapse, saying "insufficient oversight" of the city's bridge inspection program contributed to the continued deterioration. PennDOT contracted inspectors on behalf of the city whose failures contributed to the bridge's inability to support the loads it was rated for, according to the report.
"Contributing to the collapse were the poor quality of inspections, the incomplete identification of the bridge's fracture-critical members ... and the incorrect load rating calculations for the bridge," the report says.
The report said the deteriorating legs should have been labeled as "fracture-critical," which would have forced more hands-on inspections and repairs.
During a meeting last month, NTSB Chair Jennifer Homendy said the city should have closed and repaired the bridge more than a decade before the collapse.
The NTSB ended its report by making recommendations to several agencies, including the Federal Highway Administration, PennDOT and the city. The agency recommends PennDOT and Pittsburgh work together to evaluate the effectiveness of changes made by the city to ensure that bridges are safe for people to use.
Looking forward, the NTSB asked for the Fern Hollow Bridge collapse to become a case study for future use in bridge inspection training courses, emphasizing the need for regular maintenance and repairs.
The collapse happened just days into the Gainey administration and the administration says it wasn't responsible for the bridge's condition or collapse, but says it is picking up inspection and repairs to prevent such incidents from happening again.
PennDOT released a statement, saying:
"PennDOT has been closely engaged with the National Transportation Safety Board (NTSB) throughout its investigation into the collapse of the Fern Hollow Bridge. PennDOT takes its oversight responsibilities seriously, and looks forward to continued partnership with the City of Pittsburgh and the NTSB as we work to respond to the recommendations in the report—many of which we have already proactively implemented."