Permanent repairs to the Richmond-San Rafael Bridge after falling concrete closed the key North Bay commuter artery for hours Thursday were postponed until next week due to rain in the weather forecast.
Caltrans engineers made emergency fixes to an expandable joint on the bridge’s upper westbound deck to reopen all lanes Thursday evening. They decided overnight Saturday to swap out a temporary metal plate acting as a patch with a larger one to make for a smoother ride over the tolled east-west connector.
Replacement of the joint — which expands or contracts from varying temperatures and weight loads — to ensure more chunks of concrete don’t break off and drop onto the lower eastbound deck was set to begin early this week. With heavy rain and strong winds expected, that work won’t start until at least Feb. 18.
The failing of the expansion joint in the middle of the bridge disrupted tens of thousands of motorists across the region. The repair, however, is considered part of routine upkeep for a steel bridge like the 5.5-mile span over the San Francisco Bay, which opened in September 1956.
“There’s never a good time for this to happen,” said John Goodwin, spokesman for the Bay Area Toll Authority, which oversees collections over the Bay Area’s seven state-owned bridges. “This is the kind of thing, though, that you absolutely expect to pop up periodically. There’s really nothing unusual about it.”
During the revamp job, which Caltrans expects will take 10 overnight shifts over two weeks to complete, traffic will be affected between 9 p.m. and 4 a.m., though the bridge will remain open to allow vehicles to cross in one lane in each direction.
The 62-year-old bridge has a history of similar problems, when concrete has broken off and fallen onto the lower deck, Goodwin said. What made the latest incident different, he said, was that it happened toward the center of the bridge — with a chunk hitting and damaging the car of a Sonoma resident — rather than at its edges where it’s happened in the past.
The anomaly was not cause for additional concern, he said, nor should there be worries among its daily 82,000 motorists about the bridge’s structural safety. The critical link between Marin and Contra Costa counties had an almost $800 million seismic retrofit in 2005, as well as a $74 million expansion to add a third lane on the lower deck that opened last year.
In addition, the Bay Area Toll Authority spent $46 million on maintenance, including repair or replacement of some of the other hundreds of expandable joints, over the past five years. In the next decade, another $80 million is budgeted for similar work, Goodwin said.
Based on 2017 Federal Highway Administration data, a Washington, D.C.-based transportation infrastructure policy group found the Richmond-San Rafael Bridge to be structurally sufficient.
The American Road & Transportation Builders Association showed a deck condition score of 7 on a 9-point scale, while the superstructure and substructure were both rated a 5, or fair condition, which is just a point above what the highway administration deems deficient.
While Caltrans awaits the permanent bridge repair, the state road agency considers the temporary metal patch safe.
“The Richmond-San Rafael Bridge remains safe and open to the public,” Tony Tavares, a Caltrans district director, said in a statement. “Out of an abundance of caution, Caltrans engineers will continue to regularly monitor the bridge until the permanent repair is made.”