SAN MATEO (KCBS) — San Mateo Bridge commuters will have to wait a little longer for Caltrans to open one of its westbound lanes. Emergency repairs are now expected to stretch into Friday, possibly affecting the morning commute.

The west bound right lane has been closed since a 10-inch crack was discovered in a steel beam beneath the road-deck during a regularly scheduled inspection on Tuesday.

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Bob Haus of Caltrans assured the bridge is not in any imminent danger of collapse.

KCBS’ Rebecca Corral Reports:

“It took a little while longer to fabricate the plates that we’re using to fix the crack. Once we get out on sight we’ll have a better idea of how long a project is going to take.

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The beam, designed to help the bridge survive an earthquake, is part of a seismic retro-fit according to Haus. “It’s part of the mechanism that allows the bridge to move side to side up to three feet,” he added.

Engineers didn’t think it was a good idea to put off the fix until the weekend when the bridge has less traffic.

Haus said that leeway more or less allows the bridge to roll with the punches in the event of an earthquake.

Haus estimated the repairs should be completed by Friday, but did not specify if they’d be ready for the morning commute or not. While the repairs are an inconvenience to commuters, Haus said it’s all in the name of safety.

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