New Bay Bridge fights war against water

OAKLAND -- When water leaks sprung in the decks of the unbelievably expensive replacement Bay Bridge during a recent storm, people asked a logical question: Is that bridge really going to last 150 years?

After all, the steel and reinforced concrete span is outdoors where rain, fog and the salty bay water could ultimately transform the gleaming structure into a rusted hulk. Just look at the old eastern span now under demolition.

Caltrans insists the new span is here for the duration but concedes that water -- or at least, water in the wrong places -- will be an ongoing threat.

"The bridge is literally a battle zone between steel and water," veteran Caltrans engineer Brian Maroney said. "It's a war that we will eventually lose. But we have taken a number of extra measures to fight corrosion, and if we do a good job maintaining the bridge, we can stay ahead of it for 150 years or more."

Not everyone is so sure, given Caltrans' series of water-related setbacks on the span since construction started 10 years ago.

First, water seeped into ducts that held steel tendons used to strengthen the reinforced concrete in the skyway segment of the span.

In March 2013, a third of 96 very large high-strength steel bolts -- 3 inches in diameter and up to 24 feet long -- inside key seismic stabilizers snapped. Experts say pooled water in the bottom of the bolt casings may have contributed to the failures.

Then the rains came in mid-January, and water leaked into places beneath the travel deck where water isn't supposed to go.

"It looks like incompetence," said Charles McMahon Jr., an engineer and retired chairman and professor emeritus of the Department of Materials Science and Engineering at the University of Pennsylvania.

Water's destructive effect on steel is well-known and preventable, he said.

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New Bay Bridge fights war against water