The Bay's Questionable Bridges



In light of last year's disasterous Minneapolis bridge collapse, which has just been linked to the steel gussets that hold the bridge's support beams together, the National Transportation Safety Board wants states to inspect similarly constructed bridges. Last year, MSNBC put together a state-by-state breakdown of so-called "structurally deficient" and "funtionally obsolete" bridges. So just how many are in the East Bay?

A lot. One hundred and seventy-nine to be exact - about 73 in Oakland alone (Berkeley has two). But is it cause for alarm? According to the article, "A structurally deficient bridge is closed or restricted to light vehicles because of its deteriorated structural components. While not necessarily unsafe, these bridges must have limits for speed and weight. A functionally obsolete bridge has older design features and, while it is not unsafe for all vehicles, it cannot safely accommodate current traffic volumes, and vehicle sizes and weights."

Immediately following last year's bridge disaster, local media turned its attention on local bridge safety, finding that while most had a 90 or above rating, some, like Alameda's High Street Bridge, had a low 46.4 rating. (The Minneapolis bridge had a 50 rating.) However, in an article in the San Francisco Chronicle, Lawrence Bank, a professor in the Department of Civil and Environmental Engineering at the University of Wisconsin at Madison, says because the rating is derived from a formula, it's difficult to convert the number into an understanding of the bridge's relative safety.

Proposition 1B gave $125 million as seed money to attract federal funds for bridge seismic retrofits, but Caltrans officials say they've only got half the funding needed. Caltrans currently performs structural maintenance inspections every two years.