Transcript for New Images Reveal Moment Washington Bridge Collapsed
dramatic pictures from washington state, the bridge giving way under drivers traveling for the holiday weekend. Tonight david kerley with the images the moment that bridge collapsed and the new concerns growing tonight. Reporter: Surveillance video captured the moment of the collapse. The bridge falling away, two cars plummeting into the river. Investigators say an oversize truck struck the bridge's steel girders, possibly triggering the collapse. Today ntsb officials were interviewing the truck driver hoo determine what went wrong. This isn't the first time the truck hit the bridge but never before with catastrophic results. This week's collapses are renewing concerns about the nation's aging infrastructure. One out of every nine of this country's bridges is structurally deficient, meaning part of the bridge has been rated poor, nearly 67,000 bridges. Some of them get a lot of traffic. We make 200 million trips over a structurally deficient bridge every day. We visited one of those bridges. Washington d.C.'S key bridge with former ntsb investigate jim wildy. This is exactly what you are really worried about, right? When the concrete falls away the underlining steel can corrode. 20/20's deborah roberts looked at what one watch dog calls the most dangerous bridge in the country, tap an zee. That's creaky. That's scary. Deficient but inspectors say it's safe. The day they say it's not we're in for big trouble. Possible trouble in every state in the country. David kerley, abc news,
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