Although bridge consultants suggested making the Interstate 35W bridge over the Mississippi River structurally redundant as far back as 1999, the Minnesota Dept. of Transportation did not act wisely on those recommendations, according to a report just released by the Minnesota State Legislature.
The report recommends new policies but does not delve into the cause of the I-35W collapse. It also comes weeks after state lawmakers signed a $38-million compensation package for the victims and their families, relieving the state from further liability.
The more than 100-page report, prepared by law firm Gray Plant Mooty, recommends that the state Legislature require annual in-depth inspections of all fracture-critical bridges and a replacement plan for all such bridges that are rated "poor" for two or more years in a row.
Staff Structure Was "Diffused"
The report faults a "diffused" bureaucracy, recommending an organizational review of MnDOT. It also faults Federal Highway Administration for not disseminating findings from a previous gusset-plate mishap in Ohio and applying lessons learned to fracture-critical bridges in other states, even though the failure was well documented in industry literature.
Factors of concern include an "oral culture" at MnDOT, where decisions regarding bridge maintenance were not clearly documented, the report says. For example, the maintenance supervisor for the bridge "did not typically receive copies of the fracture-critical inspection reports."
The report notes that "after eight years of expert evaluation, recommendations by experts to add redundancy to the bridge were not acted upon." In 2000, the report continues, HNTB Corp., Kansas City, Mo., presented various concepts for adding redundancy to the bridge, which was "identified by MnDOT's State Bridge Engineer as an important safety factor."
But MnDOT did not choose to proceed with HNTB. Rather, it issued a Request for Interest soliciting other consultants and chose San Francisco-based engineering consultant URS Corp. to conduct reports, which were still ongoing when the bridge collapsed Aug. 1, 2007.
Although a 2006 URS preliminary report recommended that MnDOT redeck the bridge at a cost of $13 million for added redundancy, it was later "told that the redecking option was going to be deferred for 14-16 years."
MnDOT eventually chose the alternative option of a $3.5-million deck overlay project, at a cost of $15,000 a year, with deck replacement and steel strengthening to come sometime between 2017 and 2022 for $15 million.
Funding a Possible Factor
The state report says that financial considerations "may have adversely influenced decision-making," but stops short of blaming MnDOT for making unsafe cost-cutting decisions. However, it claims that MnDOT's bureaucratic structure "did not adequately address bridge conditions and safety."
MnDOT Commissioner Tom Sorel noted at a May 21 legislature-committee hearing that a few of his staffers had seen a preliminary draft of the report, so "we � like you � are seeing the final document for the first time today. The limited review afforded MnDOT is different than the more extensive review and comment process normally afforded agencies under audit by the Office of Legislative Auditor."
Sorel emphasizes that the remaining bridges in the state were safe, that MnDOT was exceeding federal guidelines in performing inspections of its steel-truss bridges, and that it was working to improve its internal processes and policies.
"It would be premature to draw any conclusions regarding the cause of the I-35W tragedy prior to release of the National Transportation Safety Board report," he says, adding, "MnDOT's inspection and maintenance of state bridges meets or exceeds federal guidelines and standards. Minnesota bridges consistently rank among the best in the nation."
"As was repeatedly stressed with the Gray Plant Mooty attorneys who crafted this report, addressing the condition and safety needs of our bridge system never has been - and never will be - subject to question due to budgetary concerns," Sorel adds.
Gusset Concerns Grow
Red flags on gusset plates in other states were ignored, the report notes. A 1996 structural failure due to buckling gusset plates, which is believed to be a factor in the I-35W collapse, occurred on Interstate 90 near Cleveland, while a bridge-painting contractor was on site.
But "MnDOT reports that none of its employees were aware of the failure of the Grand River Bridge," the legislature's report states. "The Federal Highways Administration [sic]...should take steps to ensure that information on bridge deficiencies is shared with MnDOT and other state departments of transportation in the future."
NTSB warned in a preliminary finding earlier this year that bent gusset plates are a leading theory into last year's bridge collapse, which killed 13 people and injured 145. NTSB says the gussets were potentially underdesigned from the start, though observers have warned that faulty maintenance was more of a factor than design.
Minnesota Gov. Tim Pawlenty (R) has asked MnDOT to review the state policy findings and report on corrective action. But he denies that maintenance was a factor. NTSB "said that bridge inspections would not have identified the error in the design of the gusset plates," Pawlenty notes in a May 21 statement.
NTSB Findings Questioned
The legislature's report, whose intent is to outline public-policy decisions, does little to dispel questions over the cause of the collapse, including NTSB's independence in its probe of the tragedy.
Lawyers representing the victims say they are still waiting for the NTSB's final report before pursuing further legal action. But they already have blasted its forensic methods and preliminary findings.
URS and paving contractor PCI Inc., which had materials staged on the bridge at the time of collapse, are likely targets for further litigation, lawyers say, although no lawsuits have yet been filed. The state has agreed to settle litigation for $38 million, which would relieve it and its public agencies, including MnDOT and the University of Minnesota, from liability.
Personal-injury lawyers say the NTSB's final report will open up the necessary evidence needed for discovery to pursue legal action against private companies, which are not protected under the state compensation package.
"I don't think it would be responsible at this moment to file a lawsuit because of the NTSB's unwillingness to share any evidence," says Chris Messerly, a local attorney representing about 110 victims on a pro-bono basis. He has hired structural consultant Thornton Tomasetti, New York, to conduct its own investigation into the cause of last year's collapse.
NTSB says it is using investigative data, including gusset findings, from forensic engineer Wiss, Janney, Elstner Associates, Northbrook, Ill., which the state hired to perform a separate review. But those investigators have refused to hand over findings under an NTSB gag order they signed last year.
"The fox is in the hen house," says Messerly, adding, "How can any expert confidently give an opinion if they've never seen one piece of evidence?"
NTSB and Wiss, Janney have repeatedly denied the possibility of information corruption. Still, critics argue that NTSB compromised its independent reputation by guarding the state's probe under a veil of secrecy. The federal report is expected to arrive by the fall.
"Obviously, the NTSB recognizes that they are not sufficient experts in bridges," Messerly adds. "They've done so many things here that even if they've reached a proper conclusion, everyone will question it."