After I-35W bridge collapse, Minnesota leads nation in bridge inspections and maintenance

ROCHESTER, Minn. (KTTC) – It’s one of those moments you remember in detail, where were you when the I-35W bridge in Minneapolis collapsed?

15 years ago on Aug. 1, 2007, the interstate bridge, carrying rush hour traffic, crumbled beneath itself. After investigation, we would later learn 111 vehicles were on the bridge during the collapse. The tragedy took 13 lives and hurt 145 people.

According to the National Transportation Safety Board, the cause of the collapse “was the inadequate load capacity, due to a design error . . . of the gusset plates at the U10 nodes, which failed under a combination of (1) substantial increases in the weight of the bridge, which resulted from previous bridge modifications, and (2) the traffic and concentrated construction loads on the bridge on the day of the collapse.”

“It’s quite amazing that the bridge stood as long as it did with the gusset plate being half as large as they should have been,” MnDot Asst. District 6 Engineer Program Support Nick Haltvick said.

The disaster changed so many lives that day - including Halvick’s.

“That’s when I knew I wanted to be a bridge engineer,” he said.

The tragedy prompted special funding to state infrastructure. More than 170 bridges were rehabbed or replaced, including 33 in southeastern Minnesota.

“We have a much more robust inspection program than we did 15 years ago,” Haltvick said.

According to Haltvick, majority of bridges in the state are inspected every two years, in some cases, every year.

“Unfortunately the disaster was a tragedy and I don’t want to minimize that at all. But the little bit of light we did get is that Minnesota is truly a leader in bridge inspection, keeping everyone safe, but also maintenance and construction practices,” Haltvick said.

In southeastern Minnesota alone, MnDot has three teams solely dedicated to bridge inspection.

“It’s amazing going to different parts of the country and learning about the challenges that they are still dealing with 15 years later,” Haltvick said. “We’re very fortunate to have the funding that we’ve had to get rid of some of the bridges in our inventory. Big thing moving into the future is we gotta have the funding to keep that practice going.”

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