Is the Bay Bridge Cracking Up?

I was driving over the San Francisco-Oakland Bay Bridge recently when the local public radio's news program came on, with a report on the safety of the bridge. The state transportation agency, Caltrans, closed the bridge for four days to do a big part of the replacement of half of the bridge to make it safe for earthquakes. While it was closed, Caltrans found a big crack in one of the beams, which meant they had to rush to get a replacement part machined and installed before the bridge was scheduled to reopen. They ended up extending the closure for two hours, which was a relief for commuters like myself, since they were warning people that it may have to be closed an extra day. Caltrans was all over the news, with its spokesman bragging that the bridge was safer than it was before the closure.

As I was crossing the bridge the afternoon that it was reopened, I was feeling rather positive about Caltrans, and the bang-up job they did during the closure, and I was happy not to have to drive 20+ miles out of my way to use another bridge. It was a nice evening, the traffic was light, and I had the radio on to the local public radio's news program. So when the reporter announced his guest, a professor of civil engineering from UC Berkeley who is an expert on steel bridges, I anticipated another laudatory report on Caltrans' feat. As it turns out, the profesor was not so bullish on the bridge's safety. He practically accused Caltrans of white-washing the safety situation with the bridge. He explained that the crack that they fixed was a fatigue crack, and if there was one that big, there are almost certainly others that may only be hairline cracks at this point, invisible to the naked eye. If one of those cracks were to result in a beam breaking on the bridge, there is a risk that the bridge could be damaged with catastrohpic results. He compared the situation from an engineering perspective to a bridge that collapsed in Ohio where 46 people were killed.

The solution, according to the professor, would be to conduct a full inspection of the bridge using one of the several high-tech methods for detecting hairline cracks that are available. If the load on the bridge could be reduced, the inspection could be done with the bridge in use. The professor suggested that the bridge be closed to loaded trucks, which cause the most stress on a bridge, but open to regular commute traffic. It was only a five minute report, and did not even mention what might be the consequence of a major earthquake on the Bay Bridge, if it does have hairline cracks.

Our state, controlled by the two capitalist political parties, chose not to do what was necessary to make the bridge as safe as possible. It makes me wonder what choices were made prior to the interstate collapse in Minnesota a couple of years ago. What with the cost of a closed bridge to the trucking industry, and business in general, I guess it's just too expensive to worry about safety too much.