The chair of the National Transportation Safety Board said the gusset plates supporting the I-35W bridge were half the thickness they should have been. Mark Rosenker said the original design was at fault and bridge inspectors had little chance of spotting the problem once the bridge was built.
"The national bridge inspection program and its standards are aimed at detecting conditions such as cracks and corrosions that degrade the strength of the existing structure. They do not and are not intended to detect errors in the original design."
Since the bridge collapsed on Aug. 1, 2007, Gov. Pawlenty and Lt. Governor Carol Molnau have been sharply criticized over the lack of money being spent on the state's transportation system. There were questions raised about MnDOT's bridge inspection process and whether the department disregarded recommendations on ways to fix the I-35W bridge because it cost too much.
The governor said he warned critics not to jump to any conclusions.
"I think you're going to see in hindsight, a year from now or two years from now when the NTSB report is final, that much of what was said in these past months will turn out to be inaccurate."
Pawlenty has ordered MnDOT to do a thorough review of the 23 state bridges with truss designs to make sure the current weight restrictions fit with the gusset design. He also wants MnDOT to assist in reviewing the 36 local bridges with similar designs. Pawlenty wants the reviews done by June.
Dan Dorgan, Minnesota's state bridge engineer, says the reviews should not make anyone fearful about driving over a bridge in Minnesota. He said he and other bridge inspectors are pleased to see the NTSB is getting closer to pinpointing the cause of the collapse.
"I think all of us spend all of our careers trying to ensure that it never happens but yet it did so I think there might be a small measure of relief at this time for those in the industries to note that we are seeing the beginnings of the cause..."
While the debate over why the bridge collapsed could be settling down, the larger debate over transportation funding is heating up.
On Monday, the governor proposed a bonding bill that includes a record amount of state borrowing for bridge repair and replacement. The plan would borrow $416 million for transportation projects -- $225 million would be dedicated to local bridges.
DFL Senate Transportation Chair Steve Murphy said Pawlenty's plan does not do enough. He wants a larger funding package passed into law. Murphy pushed a package through last year that would have increased the gas tax by 7.5 cents per gallon and would have increased the sales tax in the metropolitan area to pay for transit improvements. Pawlenty vetoed the package.
Murphy also called on Pawlenty to remove Lt. Gov. Carol Molnau as transportation commissioner. He said the senate would take action if the governor does not comply with the request.
"Let's just say her confirmation is going to be voted on this year and I doubt that she will survive the process."
The governor says he stands by Molnau. He also said he hopes that he and DFL legislative leaders can work out an agreement on a broader transportation package when lawmakers return in February for the 2008 legislative session. Pawlenty offered no specifics on how they get that done.