San Francisco Bay Bridge to Close for Replacement

The San Francisco-Oakland Bay Bridge, since 1936 the main artery between San Francisco and the rest of the country, will close tonight as crews ready the $6.4 billion replacement of its earthquake-damaged eastern span.

From 8 p.m. tonight until 5 a.m. on Sept. 3, the bridge carrying about 280,000 vehicles a day along Interstate 80 over San Francisco Bay will be closed, the California Transportation Department said in a statement. When the 2.2-mile (3.5-kilometer) span reopens next week, drivers will travel across a replacement designed to withstand the type of earthquake that occurs once every 1,500 years.

Since 1997, when officials decided to replace the eastern span of the bridge that partially collapsed in the 1989 Loma Prieta earthquake, the cost has swelled to about $6.4 billion from $1.3 billion, while the opening was delayed six years.

“Most people would agree with the criticism that it shouldn’t have taken as long as it did or cost as much as it did,” Andrew Gordon, a spokesman for the agencies overseeing the project, said by telephone. “That said, they’re getting a beautiful new bridge that rivals anything in the Bay Area. More importantly, they’re also getting one of the most seismically safe bridges in the world.”

Unfinished Work

Even after the span opens to traffic, it won’t be done. In December, Caltrans crews plan to remove plates installed in the undercarriage as a temporary seismic fix after steel rods snapped during testing this year, Gordon said. The plates are designed to move during an earthquake. After they’re removed, the bridge will be reinforced with steel saddles, Gordon said.

Meanwhile, Caltrans will test hundreds of bolts similar to 32 that snapped in March during testing after they became brittle on exposure to hydrogen, he said. There’s no reason to believe the other bolts are vulnerable, he said, though some may degrade over time due to corrosion.

The bridge is California’s most traveled. The eastern and western sections meet at Yerba Buena Island, site of the former Treasure Island U.S. Navy base. The new section will have two parallel spans, each with five traffic lanes, 10-foot shoulders and a bicycle path on the eastbound side.

When construction began in 2002, planners forecast completion in five years. In 2005, lawmakers passed a $1 toll increase to cover overruns.

During the Labor Day weekend closing, Bay Area Rapid Transit, the regional subway and rail network, will expand service to 24 hours a day, according to a press release.

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