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 a dozen 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. And on Monday, Caltrans confirmed to NBC Bay Area, that there were actually 13 vulnerable spots on the bridge.
"It's an 80-year-old tunnel. It is an old structure," Caltrans spokesman Myeast McCauley said.
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.
Liz Gustin of Kansas City was the driver who told NBC Bay Area two weeks ago that she feared for her life when the concrete chunk fell.
"It was big enough to totally take up the windshield," Gustin said in an exclusive interview with NBC Bay Area. "I definitely thought it would be a head-on collision crash. We were screaming in the car."
NBC Bay Area's Cheryl Hurd and Bob Redell contributed to this report.