The San Francisco-Oakland Bay Bridge will likely stay closed through the weekend, state transportation officials said Friday, and they are unsure if it will open in time for Monday's morning commute.
Construction crews on Friday continued a third full day of emergency repairs but had to stop work while waiting for more materials to be ordered.
State Transportation Department spokesman Bart Ney said the goal for reopening is Monday, but he could not ensure that will happen.
Crews are furiously working to fix a section of the bridge where two rods and a crossbar broke and fell onto westbound lanes Tuesday. The pieces were part of major repairs done over Labor Day weekend.
Repair crews have been trying to install four new steel rods. The rods will then undergo strenuous testing, which likely will involve inspectors waiting for windy conditions to determine how the repairs will hold up.
Meanwhile, Bay Area commuters struggled a third day Friday without arguably the region's most important traffic artery.
Ridership on the Bay Area Rapid Transit system has risen dramatically since Tuesday's accident. More than 437,000 people rode the system Wednesday, a single-day record in BART's 37-year history.
Officials say strong winds likely played a role in the bridge failure, heightening concerns by some experts about the integrity of the repair and the bridge's safety in an earthquake. The 1989 Loma Prieta earthquake caused a 50-foot section of the bridge's upper deck to collapse onto the deck below.
Scientists in 2008 said there is a 63 percent probability of a quake similar to the 1989 temblor in the Bay Area over the next 30 years.
The main contractor on the repairs that failed, C.C. Meyers Inc., stood by its work, but deferred to Caltrans to determine why the pieces failed, spokeswoman Beth Ruyak said.
Bonner said commuters shouldn't be worried about the bridge's overall structure.
"There's no significant risk of catastrophic failure of the bridge itself," he said.