The Toll Bridge Oversight Committee of the Metropolitan Transportation Commission decided on a $150 million plan to replace grout protecting underwater sleeves to protect hundreds of steel rods designed to stabilize the bridge in a major quake that could be damaged by exposure to water.
The committee also agreed to spend $1 million for increased monitoring of possible corrosion.
“Although this is money we would rather not spend, it’s money well-spent,” said Steve Heminger, the commission’s executive director, according to the San Francisco Chronicle newspaper.
The single-tower suspension span opened in 2013 after taking 10 years longer and costing $5 billion more than originally proposed.
But the new structure has seen a litany of problems, ranging from unexpected corrosion caused by water leaks and defective steel rods.
The steel rods that failed were part of the bridge’s seismic stabilization system and did not pose a threat to the bridge itself, but raised doubts about construction and caused widespread embarrassment to the state Department of Transportation, commonly known as Caltrans.
The rods failed after being left outside for years exposed to rainwater, and Caltrans also discovered saltwater leaking into the bridge’s lower foundation.
After crews had drained water several times, Caltrans said some of the sleeves containing the rods had not been sealed properly if at all, leading to the $150 million re-grouting plan.
Caltrans Chief Engineer Brian Maroney said the re-grouting should keep water from reaching the rods and causing further corrosion.
Maroney said the bridge still should be adequately protected in case of earthquake.
“Everything in the Bay Area will move in an earthquake, including this tower,” he said.
“I’m not worried . . . the bottom of this tower is not going anywhere,” he said.
The new span was proposed to replace the eastern span of the original bridge, which was badly damaged in the Loma Prieta earthquake of 1989.
The quake, which struck during the opening game of the World Series, was ultimately determined to have measured 6.9 on the Richter scale.