Update (2/22/24): A spokesperson for Pittsburgh Mayor Ed Gainey, who took office just 25 days before the Fern Hollow collapse, responded to Wednesday’s NTSB findings that the city “did not have sufficient personnel or budgeted funds for bridge maintenance or repair” in the years leading up to the collapse.
City communications director Maria Montaño said in an email to PublicSource that Gainey’s Bridge Asset Management program, started in 2022, has reexamined inspection reports and load ratings for city-owned bridges since the January 2022 Fern Hollow disaster.
While the city has ramped up funding for bridge maintenance under Gainey, Montaño said “funding remains an area of focus,” and the city is working with consultants to find new funding sources to “get us to a point where we are being proactive with bridge maintenance and repair.”
Montaño said the city’s red tape around procurement and contracting has slowed bridge work in the past, and that it is working with consultants and PennDOT to implement “procurement best practices” to speed work along.
Reported 2/21/24: Federal investigators reported that Pittsburgh’s Fern Hollow Bridge collapsed in 2022 because the city failed to take action on decades of warnings from state-picked inspectors — while inspectors themselves made critical errors that contributed to the disaster.
“Maintenance and repair recommendations were repeatedly made to the City of Pittsburgh, however they failed to act on them,” said Steve Prouty, a structural engineer and investigator-in-charge with the National Transportation Safety Board [NTSB], during a meeting to determine the causes of the collapse. “This led to progressive deterioration and structural failure of the bridge.”
Collapsed Pittsburgh bridge and 174 others rated poor in county drive home need for investment
The bridge collapsed early in the morning on Jan. 28, 2022. Multiple vehicles and a city bus fell with the 450-foot bridge into a Frick Park ravine, causing injuries but no fatalities. The collapse spurred the administration of Mayor Ed Gainey to emphasize bridge upkeep during his first year in office, but it also highlighted a staggering backlog of maintenance needs among the region’s hundreds of bridges.
The NTSB approved a report on the cause of the Fern Hollow Bridge collapse Wednesday, wrapping a probe that lasted more than two years.
“In our review of the reports, we found numerous inspection findings that were, with few exceptions, documented year after year,” Prouty said.
Investigators found that clogged drains led to extensive corrosion to all four of the bridge’s legs, until the southwest leg gave out, triggering the full collapse.
A transcript of the investigators’ 2022 interview with state-contracted bridge inspector Tim Pintar showed that Pintar flagged drainage issues multiple times over the years.
“The number one problem was the clogged scuppers and downspouts on almost all their bridges,” Pintar told investigators in 2022. “And I tried to preach that the whole time, and nothing ever got done. I mean, just simply clean the stuff, you know?”
In a written response to NTSB questions in August 2022, city officials wrote that “The City did not have a preventative maintenance schedule to clean the storm water drainage system” and that the city never hired a contractor to clean the drains between January 2019 and the collapse. The city found no records of an earlier time in which it cleaned the storm drains.
Gainey’s office did not immediately comment on the report.
NTSB staff also found that errors by inspectors and engineers contracted by the city contributed to the disaster.
A fateful miscalculation in 2014 contributed to the catastrophe eight years later.
Updated: Report calls for prompt fixes to dozens of bridges. City’s 2023 budget barely starts the process.
That year, the bridge was given a load limit of 26 tons to account for corrosion. But the CDM Smith engineers contracted by the city made multiple errors, investigators said. Engineers assumed the bridge had 3 inches of asphalt, and calculated its load-bearing capacity using that flawed metric. But after the collapse, investigators found 6 inches of asphalt on the bridge, indicating that the bridge’s load limit had been set too high.
The 26-ton limit was also assigned without properly accounting for the effects of holes in bridge supports, investigators said.
“Had contractors from the City of Pittsburgh correctly calculated and accounted for the effects of [material] loss and other factors back in 2014, the Fern Hollow Bridge would have, should have, been closed,” said NTSB board Chair Jennifer Homendy during Wednesday’s meeting.
An NTSB board member said Wednesday that the bridge’s limit, if properly calculated, would have been just three tons, instead of 26 tons, and low enough that the bridge would have been fully closed to traffic.
An engineer involved with 2009 repairs told investigators that there were plans to fully replace cross-braces and to add a protective coating to the bridge’s legs — but the city chose not to go ahead with the repairs because of impacts on traffic and because “it was the wintertime.”
The NTSB placed responsibility not only with the city, but with the inspectors who check each bridge every year or so. Inspectors work for engineering firms contracted by PennDOT, and are meant to follow a rigid set of federal and state guidelines.
Investigators said noncompliant inspections may have resulted in an incomplete understanding of the bridge’s disrepair.
“Superstructure condition ratings did not reflect the true condition of the bridge and should have been lower,” Prouty said.
On a frigid and fiery night one year ago, a train upended lives in East Palestine
While components of the bridge that are critical to its stability are meant to be inspected annually, instead of every two years, investigators found that the bridge’s legs were incorrectly excluded from this category — and therefore excluded from the more frequent inspections.
NTSB officials commended Gainey and his staff, who entered city hall just 25 days before the bridge collapsed, for their efforts at improving bridge maintenance in the city. Gainey created a dedicated bridge unit within the city’s Department of Mobility and Infrastructure and signed a $1.5 million contract with engineering firm WSP USA to create a comprehensive plan, detailing each of the city’s bridges and outstanding needs.
Those needs, though, likely go far beyond the city’s current means to pay for them.
Kent Harries, an engineering professor and bridge expert at the University of Pittsburgh, said that while the Fern Hollow collapse and the NTSB’s findings could spur reform in how local governments handle bridge maintenance, a lack of resources is still likely to constrain those efforts — leading to deferred maintenance, and ever-increasing issues and costs.
“If I never visited a doctor until I turned 50, I probably wouldn’t be in that good a shape, regardless of the health care I am able to get after age 50,” Harries said. “Fern Hollow is a particularly poignant illustration of what happens when you defer maintenance.”
The NTSB called for PennDOT to prepare a report on the effectiveness of the measures Gainey has taken to improve the city’s bridge upkeep.
Charlie Wolfson is PublicSource’s local government reporter and a Report for America corps member. He can be reached at charlie@publicsource.org.
