Skagit River bridge collapse: Not the only one waiting to happen (+video)(Read article summary)
The collapse of the I-5 bridge over the Skagit River is a reminder that thousands of bridges in the US are in serious need of repair or replacement. President Obama proposed a "Fix it First" program, but the budget 'sequester' may have squelched that.
The bridge that collapsed into the Skagit River north of Seattle will get a short-term patch within weeks, officials say, keeping this busy portion of the I-5 interstate open while the crunched original is replaced.
"We will install a temporary span on the bridge that will restore traffic while we build a safe and durable permanent span adjacent to it," Gov. Jay Inslee said in a statement Sunday. That permanent replacement should be ready by early autumn.
That’s good news for commuters and travelers along this busy highway through the Pacific Northwest into Canada now poking their way along other river crossings. But it’s also a reminder that many older bridges around the country are at risk, in serious need of repair or replacement.
“Thousands of bridges around the US may be one freak accident or mistake away from collapse, even if the spans are deemed structurally sound,” reports The Associated Press.
“The crossings are kept standing by engineering design, not supported with brute strength or redundant protections like their more modern counterparts,” the AP reports. “Bridge regulators call the more risky spans ‘fracture critical,’ meaning that if a single, vital component of the bridge is compromised, it can crumple.”
Which is exactly what happened when a tractor-trailer carrying a legal oversized load clipped a girder on the I-5 bridge, sending one span and two vehicles plunging into the river below. No one was killed or seriously injured, and the truck driver (who made it across the bridge and immediately stopped) has not been charged.
Vulnerable bridges carry millions of passengers a day. Some examples: In Boston, a six-lane highway near Logan Airport includes a "fracture critical" bridge over Bennington Street. In northern Chicago, an I-90 pass that goes over Ashland Avenue is in the same category. An I-880 bridge over Fifth Avenue in Oakland, Calif., is also on the list.