(AP) - Corrosion in the Oakland-San Francisco Bay Bridge's Yerba Buena Island tunnel that caused a concrete chunk to break loose last month and narrowly miss a motorist is more widespread than the state first believed.
The San Francisco Chronicle reports Monday that Caltrans has found 12 spots in the tunnel where concrete was in danger of breaking away from the wall since a Jan. 30 incident in which a tire-size piece fell into traffic on the lower deck.
Ken Brown, a Caltrans engineer who oversees bridge maintenance, says tests found that corrosion-caused damage ranged in size and were found on both sides of the tunnel. It's possible the problem is still more extensive.
A Caltrans official says the immediate issue of falling concrete has been resolved by removing loose material from the tunnel walls.