Bay Bridge closed

The San Francisco-Oakland Bay Bridge will be closed today after a metal rod snapped on a section of the span that required emergency repairs over the Labor Day weekend.

Transportation officials braced for a traffic nightmare this morning that could spill over into the North Bay as commuters look for alternative routes to San Francisco and the East Bay.

The Bay Bridge will likely remain closed to all travel for at least 24 hours, the California Highway Patrol warned Tuesday night as engineers evaluated the damage.

In the North Bay, officials prepared for heavy traffic on the Golden Gate Bridge and Richmond-San Rafael Bridge during the morning and evening commutes.

“We will see a lot of cars tomorrow (Wednesday),” Golden Gate Bridge spokeswoman Mary Currie predicted Tuesday night.

All lanes will open at the Golden Gate Bridge’s toll plaza by 4 a.m., up to two hours early. And the bridge will have four lanes, one more than usual, available for northbound traffic this afternoon.

As well, an extra 715-passenger ferry will stand by at Larkspur to transport extra commuters, if needed, after 7 a.m. today.

Even so, spokeswoman Currie urged commuters to car pool, telecommute or take mass transit. And she warned bus passengers of the possibility of scheduling delays due to the extra traffic.

The rod, part of the emergency repair performed on Labor Day, was holding in place a saddle-like cap that was installed over a cracked steel link. On Tuesday, the rod apparently snapped, bringing down with it a steel brace roughly 3 feet long at about 5:30 p.m., said California Highway Patrol Officer Peter Van Eckhardt.

The debris plunged onto the bridge’s westbound lanes during the middle of rush hour, damaging one truck and two cars crossing the upper deck. One driver was shaken up but refused medical attention, the CHP said.

“If you look at the totality of the circumstances — you’ve got the 5:30 commute, you have a 5,000-pound piece of steel falling out of the sky. We are so fortunate that no one was seriously injured or killed," CHP Sgt. Trent Cross said.

The parts that fell were installed during emergency repairs that delayed the reopening of the bridge on Labor Day weekend.

“It is in fact the piece that was repaired,” Van Eckhardt said.

The 73-year-old bridge, which carries about 260,000 vehicles a day between San Francisco and heavily populated cities to its east, was closed over the Labor Day weekend so a football-field-sized, 3,300-ton section of the eastern span could be cut out and replaced with a new double-deck section.

While the bridge was closed for the Labor Day project, part of a long-planned seismic upgrade, crews inspected the bridge and discovered a 2-inch crack in the span. To fix it, they installed a system of braces and rods that shifted tension away from the damaged section.

Five weeks later, a big rig crashed near the same spot on the bridge that underwent the emergency repairs. The Oct. 14 accident jammed traffic for hours during the evening commute.

The California Department of Transportation, or Caltrans, had nothing to say Tuesday about what might have caused the repair job to fail. The department issued a brief statement saying only that “structural engineers and inspectors are onsite to assess the damage and will make a determination as to how long repairs will take.

“At this time, the bridge is closed until further notice,” the statement said.

Abolhassan Astaneh-Asl, a civil engineering professor at the University of California, Berkeley who has spent 20 years studying the Bay Bridge, called the initial crack a “warning sign” of potentially bigger safety issues with the bridge.

“The repair they were doing was really a Band-Aid,” said Astaneh-Asl, who criticized Caltrans at the time for rushing to reopen the bridge. “The Band-Aid broke, in essence.”

Astaneh-Asl said the failure of the repair job demonstrates the need for a longer-term solution. The span’s age and design make it susceptible to collapse, especially if commercial tractor-trailers are allowed to continue using it, he said.

“I think Caltrans is putting public relations ahead of public safety,” he said.

On Tuesday night, westbound traffic soon backed up to the foot of the MacArthur Maze, the intersection of three main highways that feed onto the bridge. It took more than three hours for the CHP to clear all the vehicles already on the bridge and close the span for repair work.

Bay Area Rapid Transit called in extra train operators for duty today to accommodate an anticipated rush of commuters.

“We will use every available extra train car we have,” said spokesman Linton Johnson.

In the North Bay, Golden Gate Bridge officials also prepared for a busy day. About 110,000 vehicles cross the Golden Gate Bridge on a typical weekday, Currie said. She called it difficult to predict how many extra cars and trucks might use the bridge today.

Over the Labor Day weekend, when Bay Area residents had advance warning of the Bay Bridge closure, the Golden Gate Bridge saw its vehicle counts increase by more than 20,000 a day. Even so, she cautioned, the two situations may be “apples and oranges.”