10 Years After Minneapolis Bridge Collapse, 'Fracture-Critical' Bridges Abound

The nation mourned the ten-year anniversary of the tragic collapse of the I-35W Bridge in Minneapolis this week. ... Grass takes the 10th anniversary of the tragedy as an occasion to evaluate the lessons from that "major wake up call" on the state of the nation's infrastructure. The obvious conclusion: that the nation has done little to improve the safety of its roads and bridges.1

Visiting for the first time in a decade, Bennett found the city’s riverfront almost unrecognizable. When he last departed Minneapolis, after two weeks spent aiding recovery efforts following the collapse of the Interstate 35W bridge over the Mississippi River, the fallen, the crumpled span was still partially submerged in 15 feet of water. It took Bennett a moment to recognize its gleaming white replacement. ... The collapse drew not just local first responders from the city, county and surrounding jurisdictions but also state and federal agencies — all of them focusing their efforts on a complex disaster site. When the about half of the 1,907-foot span fell at around 6:05 p.m., 111 vehicles, including a school bus with 63 students and driver, went with it. Seventeen vehicles landed in the water.

Less than 90 minutes later, the last survivor was rescued. A report issued after an investigation by the U.S. Fire Administration lauded the cooperative response. ... The National Transportation and Safety Board later determined the gusset plates connecting the 40-year-old bridge’s steel beams were too thin, a design flaw that had been overlooked for decades, and that years of stress and corrosion led up to the structure’s sudden collapse under the weight of rush-hour traffic.