Transcript for Bridge Collapse: Moments of Terror
And we begin tonight with that terrifying bridge collapse, just as millions of families travel america's bridges this holiday weekend. Tonight, the images of chaos in the moments after that bridge crumbled. Twisted steel. A human chain back to dry ground. Families traveling for the weekend plunging into the water below. Tonight, authorities believe they know the cause, amid new questions about how this could happen. That bridge, inspected twice last year, most recently just a few months ago. And look at this tonight. 1 out of every 9 bridges in this country, structurally deficient. And 200 million americans driving across them every day. Tonight, a list of the most troubling bridges in this country. But first, the pictures and the investigation, and here tonight, abc's nall karlinsky. Vernon, washington. Reporter: Tonight, the first video of the bridge collapse as it happened. Look closely in this surveillance video. The moment two cars were sent plummeting into the icy waters washington's skagit river. All of a sudden, there's no road to drive on anymore. Reporter:20-year-old bryce kenning, seen here sitting on top of his sinking car last night, spent today drying out his wet clothes after walking away from what seemed like certain death. He was headed northbound going 60 miles per hour when the bridge vanished in a plume of dust. I launched off that thing. Reporter: You launched? Oh yeah. Yeah. And straight nosedive into the water. Reporter: After surviving the impact, he was afraid he would drown. Car immediately starts filling with water, and that was the point where, you know, i kind of thought I might be a goner, you know, that might be it for me. Reporter: Dan sligh and his wife had been headed southbound at the same time. He dislocated his shoulder on impact -- I couldn't seat my wife in the passenger seat. I asked her ihe was okay. She wasn't responding. Popped my shoulder back in so i could unbuckle and get over to her. Reporter: This isn't the first bridge to fail with terrifying results. The 2008 collapse of the minneapolis i-35 bridge killed 13 people. And in 2009, cracks and corrosion on a boston bridge sent rocks raining down on a woman's windshield. Investigators here say a semi truck carrying an oversized load gashed through a steel beam and likely triggered this collapse. But the bridge is old, too, built in 1955 with a pile of mediocre infrastructure rankings and recent repairs. One thing investigators been looking at all day is that clean break over there. Almost as if that chunk of bridge just snapped right off. The investigation will take months to complete and in the meantime, going into this holiday weekend, traffic is already beginning to back up.
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