Officials concerned about rod corrosion on Bay Bridge

SAN FRANCISCO — State transportation officials are trying to determine if giant steel rods on the Bay Bridge's new eastern span have been damaged by exposure to water.

Transportation officials said Thursday that inspectors last week discovered that several of the galvanized steel rods that anchor the 525-foot tower to its base had been sitting in water that could cause corrosion, according to the San Francisco Chronicle (http://bit.ly/1CtJ7jC ).

Caltrans has drained the water, but officials don't know how long the rods were exposed to water and whether they were compromised. To check, they would need to remove and cut them into pieces.

A similar issue emerged last year when rainwater was found surrounding many of the 32 rods that snapped after being tensioned on the new bridge. Caltrans spent $25 million on a replacement system for the rods, which were used to anchor seismic stabilizers.

It appears the water, most likely from rain, became trapped under caulking before the tower was lowered into position starting in 2010, said Andrew Fremier, deputy executive director of the Metropolitan Transportation Commission, which oversees the bridge project.

"We have more work to do so we understand the problem as best we can," Fremier said.

To help determine if the rods were compromised, officials plan to test the water for zinc, which is left behind when hydrogen attacks galvanized steel, Fremier said.

Steve Heminger, the commission's executive director, expects a full report on the bridge's latest rod problems at a meeting of the bridge oversight panel Tuesday, said agency spokesman Randy Rentschler.

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Information from: San Francisco Chronicle, http://www.sfgate.com