Examiners Unsure of Cause of I-35 Bridge Collapse
RENEE MONTAGNE, host:
We go now to Minneapolis where this morning divers will try again to retrieve those still missing after a bridge collapsed on Wednesday. Water currents in the Mississippi River have been so dangerous that the search had to be stopped yesterday even before it got dark.
Authorities say that as many as 30 people may still be missing. The official death toll now stands at five. Minnesota officials also acknowledged that they were warned as early as 1990 that the eight-lane bridge had been labeled structurally deficient.
From Minneapolis, NPR's David Schaper reports.
DAVID SCHAPER: Investigators are still far from being certain about what caused the Interstate 35W Bridge over the Mississippi River to collapse Wednesday night, but it's becoming abundantly clear that the bridge had been in poor shape for some time.
Mr. DAN DORGAN (Bridge Engineer, Minnesota): In 1990, it was classified as a structurally deficient bridge.
SCHAPER: Minnesota state bridge engineer Dan Dorgan says federal inspectors designated the bridge as such because of significant corrosion in its bearings. And he says in the mid-1990s additional inspections found fatigue cracks. Again in 2005, the federal government rated the I-35W Bridge as structurally deficient, but apparently it wasn't a cause for alarm. According to transportation officials, the I-35W Bridge was one of 77,000 bridges in that category nationwide. Dan Dorgon says the state did some repairs over the years and stepped up inspections of the bridge, but he says those inspections did not find the need to replace the bridge was immediate.
Mr. DAN DORGAN (Minnesota Department of Transportation): We thought we had done all we could. Obviously something went terribly wrong.
SCHAPER: Minnesota's Governor Tim Pawlenty is now ordering emergency inspections of all bridges in the state of similar design.
National Transportation Safety Board investigators say they can't yet determine if structural difficulties caused the bridge to collapse, but they are getting important clues in their investigation from Army Corps of Engineers security cameras that taped the horrific event. In addition, NTSB chairman Mark Rosenker says new technology allows investigators to use a computer model to more rapidly do a failure analysis of the bridge.
Mr. MARK ROSENKER (Chairman, National Transportation Safety Board): This program, along with the video, is going to probably improve the ability for the NTSB to get the facts, to do its analysis, by months.
SCHAPER: In the meantime, divers continued to try to search through the murky Mississippi River water yesterday to recover victims whose bodies might be trapped in cars or within the twisted wreckage. But Hennepin County sheriff Rich Stanek, whose office is coordinating the dives, says the task is a difficult one.
Mr. RICK STANEK (Hennepin County Sheriff): The divers are facing some treacherous conditions in terms of the debris, the structure, the concrete, the rebar, the water conditions themselves. You know, any time you dive in the Mississippi River is not a great idea. And then you've got some unknown currents now because water is going under the bridge.
SCHAPER: Stanek says that authorities lowered the water level of the river from nine feet to seven feet by restricting the amount of water flowing through an upriver dam. But that too created dangerous changes in river current, thwarting some recovery efforts.
Stanek and other officials met with families whose loved ones are still missing. Eighteen-year-old Jessica Engebretsen was looking for her mother Sherry and says she remembers the last time she talked to her.
Ms. JESSICA ENGEBRETSEN (Daughter of Sherry Engebretsen): Last night, at 5:39, my mom called home and said she's on her way.
SCHAPER: Sherry Engebretsen worked for Thrivent Financial and was commuting home to suburban Shoreview Wednesday night. After hearing of the bridge collapse, Jessica, her sister, and her father tried calling and calling Sherry on her cell, but when she didn't pick up they knew something was wrong. The family came to a downtown Minneapolis hotel Thursday to await word and meet with Red Cross grief counselors. In the early afternoon, Ron Engebretsen was still holding out hope that Sherry, his wife of some 30 years, might still be found alive. He told reporters that for the last several months, while the I-35 Bridge was under construction, his wife usually took an alternate route.
Mr. RON ENGEBRETSEN (Husband of Sherry Engebretsen): Last night, when she came down to that location, Sherry made a decision. Obviously that decision was that she felt that she could get across the bridge because at that point you can see, going north, where we live, that she can maybe get across quickly or maybe she thought it's a direct location to our home. And she made that choice, and we support that choice.
SCHAPER: Late in the day, the Engebretsen's got the news they had been dreading. The medical examiner confirmed that Sherry was in fact one of those who died when the I-35W Bridge collapsed into the Mississippi River.
David Schaper, NPR News, Minneapolis.
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