Federal officials alerted states Thursday to immediately inspect all bridges similar to the Minneapolis bridge that collapsed into the Mississippi River.
Transportation Secretary Mary Peters signed off on an advisory that was sent by the Federal Highway Administration urging state transportation departments to conduct inspections of bridges similar to the .
There are approximately 700 such spans, according to department spokesman Brian Turmail. He did not have a list of bridge locations.
"We don't know what caused this span to collapse, but the secretary wants to make sure that states are taking every possible precaution," said Turmail.
During the 1990s, inspections found fatigue cracks and corrosion in the steel around the Minneapolis bridge’s joints. Those problems were repaired. Starting in 1993, the state said, the bridge was inspected annually instead of every other year.
Earlier in the day, governors around the nation scrambled to conduct bridge inspections on their own, ordering engineers to review the safety of thousands of structures.
States such as Missouri and Massachusetts had already identified bridges similar to the one that collapsed in Minnesota. Missouri, for instance, has 11 so-called truss bridges and planned to examine them first.
New Jersey Gov. Jon Corzine said officials planned to evaluate all 6,400 of the state's bridges, regardless of whether the structures are maintained by state, local or federal governments.
University of Missouri-Columbia civil engineer Glenn Washer said Wednesday's catastrophe may spur states to revise how they fund bridge inspection and repair.
"There are almost 600,000 bridges in this country, with an average age of 42 years," Washer said. "There is a massive effort by state departments of transportation to inspect, monitor and maintain bridges, but implementing some of the new technology and getting the work done is a significant challenge."
Problem areas identified in 2004
Nationwide, nearly 13 percent of the nation's bridges were classified as "structurally deficient" in 2004, meaning they are deteriorating, according to a report issued by the Federal Highway Administration.
Another 13 percent of bridges were classified as "functionally obsolete," meaning they are structurally sound but no longer meet transportation standards and demands.
And in 2006, 75,422 of the approximately 600,000 bridges nationwide carried a “structurally deficient” classification, with 1,160 in Minnesota alone.
In Missouri, state Department of Transportation spokesman Jeff Briggs said more than 1,600 of the 10,240 bridges in the state's highway system have been deemed structurally deficient. That figure does not include thousands of bridges under the watch of cities and counties.
Massachusetts Gov. Deval Patrick said none of his state's 27 steel truss bridges are considered at risk of collapsing, but he still asked transportation officials to review inspection records.
States such as Texas and Georgia said they were not doing anything out of the ordinary in the wake of the Minnesota collapse because officials are confident with the routine inspections of their bridges.
Texas Department of Transportation spokesman Mark Cross said every bridge on a public road is inspected at least every two years.
In North Carolina, the state transportation department inspected the only bridge that officials identified as being similiar in design to Minnesota's.
The results of the inspection of the bridge in Gaston County, which carries N.C. Highway 273 over a Duke Power canal, were not yet available Thursday evening, said department spokesman Ernie Seneca.
"That's the only one that we've identified so far as being comparable to the one in Minnesota," he said.
No other new inspections were planned, but Transportation Department Secretary Lyndo Tippett asked Thursday that work begin on a report detailing the safety of substandard bridges across the state. Tippett wants the report completed before the September meeting of the state Board of Transportation.