RICHMOND, Calif. (KGO) -- The ABC7 I-Team was first yesterday to report the cause of the falling concrete-- an expansion joint, worn down by heavy traffic. And on Friday, officials who oversee the bridge confirmed our account and revealed plans to address the problems.
Concrete falling off the Richmond-San Rafael Bridge has been a problem over the years, but it never caused a traffic jam as bad as Thursday.
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Before Thursday's car-maggedon, Caltrans had identified several expansion joints on the bridge that needed repairs-- but not the one that failed on the upper deck, an original from 1956, and it caught them by surprise.
"In the bridge industry, the joints kind of like your gutters on your house, are really important but also hard to maintain."
Andrew Fremier, a civil engineer for the Metropolitan Transportation Commission, told a board meeting Friday that the issue is simple-- cars and trucks bumping over the expansion joint, shaking concrete loose from the steel, allowing water to seep in.
And the fix is simple, "It's just concrete and steel," said Fremier. "They'll replace the joint, they'll probably upgrade the joint a little bit because there are more modern joints then were developed in the 50's, but all of that is pretty simple and will be done off hours over probably the course of several weeks or more depending on what kind of material they use to replace the joint."
County supervisors from either end of the bridge tell us, they're pushing Caltrans to step up inspections of the entire span.
Damon Connolly, Marin County MTC Member, told the I-Team, "They are inspecting it from one end to the other, to make sure that what happened here, and how do we prevent it in the future."
Amy Worth, Contra Costa County MTC Member, added, "During the course of yesterday, today, over the weekend, they will be continuing to examine the bridge and also do the repairs."
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Caltrans says the bridge is structurally safe, but they have to keep the concrete from what they call "spalling" or flaking off. Another complicating factor-- the original concrete on the top deck is lighter, less sturdy, not up to today's standards. The MTC's Legislative Affairs Director tells us that when the bridge was built in the '50's, they cut corners, even ignoring design plans, to use less steel.
"You can see the bridge has that weird hump to it, "Randy Rentschler said. "The idea was to save money by having less steel on the bridge, that's why that hump is there, it was not a design feature, so there's always indications of this bridge probably not being built to the standard that it needed to be built back in those days."
There's a consensus-- everyone the I-Team talked to said we need a new bridge there. That's the idea, but funding is years away, so crews will do their best to keep track of the problems, and patch the bridge when it needs it.
See more stories about the Richmond-San Rafael Bridge closure.
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Officials reveal plans to address problems on Richmond-San Rafael Bridge
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