California officials say they have a plan to stabilize bolts that failed earlier this year on the eastern span of the Bay Bridge.
The new span, which connects San Francisco to Oakland, is already four years behind schedule and billions over budget. And it was dealt another blow two months ago, when it was discovered that dozens of bolts failed because they were made brittle by exposure to hydrogen. Moreoever, the bolts are made from a galvanized steel that is not recommended for bridge use -–it’s too hard and prone to cracking. Those bolts, which are supposed to play a key role in the seismic integrity of the bridge, can’t be replaced.
On Wednesday, officials from the California Department of Transportation (Caltrans) met with the Bay Area Toll Authority and the regional Metropolitan Transportation Commission (MTC) to unveil its retrofit plan.
Caltrans will manufacture a steel “saddle” to fit over the bolts and hold the earthquake protection mechanisms in place. The “saddle” will cost Caltrans an extra $5 to $10 million. That’s on top of the bridge’s estimated cost of $6.4 billion– more than four times the original price tag of $1.3 billion.
Besides those broken bolts, there’s a separate set of bolts under review. These were built into the new span of the bridge in 2010, and while they're not yet showing signs of damage, they’re made from that same galvanized steel as the problematic bolts. Caltrans officials haven't reached a decision about what to do with the suspect bolts, but said they would be putting extra bolts from the same shipment through rigorous testing. Caltrans will announce whether these bolts need to be replaced at a special meeting with the Bay Area Toll Authority on May 29th.
The agency has also asked the Federal Highway Administration to conduct an independent study on the safety of the galvanized steel bolts used in the bridge.
Now, the opening date for the bridge –- originally planned for Labor Day weekend -- remains unclear. Caltrans officials said they would not fully commit to a September deadline, and MTC board members urged Caltrans to prioritize safety over finishing “on time.” One person in the MTC meeting Wednesday joked that if the bridge can’t be finished by Labor Day, they should aim for Thanksgiving because a completed bridge is certainly something to be thankful for.
Caltrans officials said they hope to decide on a date for the bridge opening by May 29th.