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Skyway may not be best bridge fix; Studies find tower plan might still be easiest solution; audit due Wednesday


December 20, 2004 Reposted from the Oakland Tribune
  By Sean Holstege

Caltrans says it wants to finish the new Bay Bridge with a plain concrete skyway, but neither its own technical report nor any panel of consultants backs up that finding.

An independent industry panel concluded with scant support that a cable-stayed tower should be built. A federal peer review team found that the currently planned self-anchored suspension, or SAS span, presented the least risk, as did Bechtel Corp. earlier this year.

And a panel of seismic experts warned that any design change could lead to catastrophe or expensive, cumbersome re-engineering.

On Dec. 8, Caltrans concluded: "The SAS has less risk of impacting the primary value, getting a seismically safe (eastern Bay Bridge span) in place as soon as possible, while at the same time giving the best value to the public and providing an aesthetically acceptable structure."

Caltrans called it a tie between the skyway or the currently planned tower.

"That's why the Bay Area delegation will have to ask some tough questions when we review the state audit," said Assemblywoman Loni Hancock, D-Berkeley.

The state auditor is due to report Wednesday how the Bay Bridge ballooned from a $1.3 billion project to one with a $5.1 billion price tag. Those familiar with the work say it will tread familiar ground to reach some conclusions about how California should manage future mega-projects.Skyway plan

for bridge fix

draws new

criticisms

Auditors got no better case for reform than it got in southern France last week, when President Jacques Chirac opened a 1.6-mile bridge featuring seven steel cable-stay towers, some taller than the Eiffel Tower. The whole bridge cost $523 million, one-tenth the cost of the single-towered Bay Bridge. Caltrans pointed out that the Millau Bridge is four lanes, not 10, spans a narrow river gorge instead of open water and is not in a seismic area.

Cost is the main reason California's transportation secretary Sunne Wright McPeak decided to revert to the plain, elevated causeway design to get from Oakland to Yerba Buena Island.

But a careful examination of four supporting technical reports shows her expected savings are limited at best and may be overly optimistic.

A series of technical panels   convened by the state in the last two months placed the cost of a skyway at anywhere between $800 million to $1.7 billion. McPeak has said her recommendation could save up to $400 million over the cost of forging ahead with the tower design picked in 1998. That tower could now cost up to $2.1 billion, the panels suggested.

But an average of all the estimates places the skyway at $1.25 billion, only $150 million less than the bid Caltrans got in May for the tower. Caltrans' own report said the state has already invested $200 million on the tower, and significant changes will be needed on other parts of the bridge to accommodate a changed design.

Caltrans' report noted that over the years the beauty, safety and cost of the new bridge have traded places in the hearts of decision makers.

A knowledgeable capitol source said McPeak's Dec. 10 call for a skyway marks "the starting move in a game of political chess."

In the Legislature's first counter-gambit, Senate and Assembly leaders Don Perata and Fabian Nuez jointly announced their appointments to a Bay Bridge task force. The panel consists of two lawmakers in each chamber, two from the Bay Area and two from Southern California. The Bay Area duo are Sen. Tom Torlakson, D-Antioch, and Assemblyman Leland Yee, D-San Francisco.

"There will be laser scrutiny on all these reports that have come out," Torlakson said. "With the fact that the administration is still stuck on making the Bay Area pay 80 percent of the cost, we're hoping the audit will show its not all the fault of the design."

He added: "It doesn't appear the skyway will save any time."

All of Caltrans' technical reports peg the earliest opening date at 2011, meaning the Bay Bridge is still only at the half-way point from the original 1997 plan for a skyway. Seven years have elapsed since then and at least seven more remain.

For almost a year, the Bay Area will be looking at a $1.5 billion fishing pier, between the time the existing skyway work ends and new work can commence on the gap between it and the island. Already Caltrans has suspended two contracts on other parts of the bridge.

"You would think that the burden of evidence would be very strongly   in favor of abandoning the current bridge construction." Hancock concluded. "The prudent thing is to move ahead with the design we've got and the construction we've started."

San Francisco engineer Joseph Nicoletti agreed, and not just because of cost. He chaired the panel in 1997 and 1998 that picked the tower, as well as the state seismic panel that evaluated the six new options last month.

"The bridge was designed as a system from Yerba Buena Island to Oakland. Now they are going to award a contract for that missing part in the middle. You have to be very careful to look at the response to an earthquake," he said.

Last month, his seismic panel warned that changing designs from the self-anchored suspension tower, carried risks.

"It is completely unrealistic to expect that a seismic design and evaluation of an alternate bridge to the SAS can be completed in a two-week time frame without the potential danger of a technical disconnect, namely an evaluation of a structure that will be different in seismic performance and reliability than the current SAS design," Nicoletti wrote.

  Caltrans has no idea yet how well a reworked bridge would hold up in a quake or what it will cost to redo other features, including two massive finished columns on Yerba Buena Island, silently awaiting a bridge to prop up.

"They're saying that among all the engineering and design considerations, the seismic safety is still an open question," said Ken Gosting, who wrote earthquake safety laws for Gov. Jerry Brown. "This whole bridge is playing out with all the elements of a classic disaster movie."

Hancock seemed to agree, saying: "With all the changes, it's getting to be like a

slapstick comedy."

Contact Sean Holstege at [email protected]

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