The National Transportation Safety Board has issued national recommendations following the collapse of the Fern Hollow Bridge in January, 2022.
Officials say there were holes on parts of the bridge and found “corrosion, deterioration, and section loss on all four of the bridge’s legs due to the continual accumulation of water and debris.
Leaves, dirt and other debris blocked drainage systems. That let water drain into areas that were not built for water flow and prevented the steel to dry.
The NTSB says uncoated weather steel needs times of dryness to “form a protective oxide coating, or patina, that resist corrosion over time.”
The report also found that PennDOT inspections showed problems with drainage, but those issues were not regularly addressed.
Other bridges across the state also show similar issues with drainage.
The NTSB is now recommending that state and federal authorities review inspections to identify “incomplete follow-up actions that need to be resolved for bridges made of uncoated weathering steel.”
The collapse of the Fern Hollow Bridge has prompted the NTSB to ask the Federal Highway Administration to “develop a process for bridge owners nationwide to perform necessary follow-up actions on bridges with uncoated weathering steel components.”
Full investigation results are expected, that will include a probably cause, in the coming months, but the NTSB wanted to make the early recommendations “due to the immediate implications for bridge safety nationwide.”