The Mercury News

News on opening plan out next week

Announceme­nt Monday will reveal if there will be a delay

- By Lisa Vorderbrue­ggen lvorderbru­eggen@bayareanew­sgroup.com

OAKLAND — Bay Area legislator­s will be the first to know Monday if the new Bay Bridge will open as planned on Sept. 3 or if the constructi­on snafus that led to broken bolts and safety concerns will force a delay.

The Bay Area Caucus will be briefed by the Toll Bridge Program Oversight Committee during a closed- door meeting in Sacramento on Monday morning and release by noon its recommenda­tions and reports to the media and the public.

The bridge team is also scheduled to outline its recommenda­tions on July 10 to the Bay Area Toll Authority, a governing board of county and city elected offi cials from the regions’ nine counties.

The opening date is the latest cliffhange­r in a saga that began 24 years ago when the Loma Prieta earthquake shook loose a piece of the Bay Bridge’s upper deck and killed a motorist.

Residents demanded a safer and prettier bridge, and after years of political intrigue, bickering over the design and cost overruns, the $ 6.4 billion span is now on the verge of opening.

Whether or not it does depends largely on the answers to two questions: Will the contractor finish in time the retrofit of two seismic stabilizer­s where 32 steel anchor bolts snapped in March? And do test data suffi-ciently reassure engineers and officials that the span’s other 2,210 high- strength steel bolts are sound?

The answer appears to be maybe.

Bridge engineers say early test results from hundreds of bolts show no evidence of further hydrogen embrittlem­ent, the phenomenon metallurgi­sts blame for the failure of 32 out of 96 rods embedded in shear

keys on the large pier east of the tower.

The team will test most of the types of fasteners for long- term corrosion in the coming months but the bridge opening doesn’t depend on the outcome. Instead, these findings will be used as the basis of a longterm bolt maintenanc­e and replacemen­t schedule.

The retrofit timeline, however, remains an open question.

To carry the loads the faulty bolts were supposed to handle, engineers propose to install on each shear key a steel saddle and hang across it superstron­g cables. The ends of the strands will be anchored on the outside of the shear key and the entire assembly will be encased in concrete.

The bridge contractor, American Bridge/ Fluor Enterprise­s, and Mare Island XKT Engineerin­g have started fabricatio­n but “in terms of an installati­on schedule, I don’t believe it has been completed yet,” said bridge spokesman Andrew Gordon.

Although Caltrans Director Malcolm Dougherty has stated publicly that the new bridge will not open until the retrofit is completed, outside experts disagree.

The Toll Bridge Seismic Safety Peer Review Panel says the existing span’s extraordin­ary earthquake vulnerabil­ity outweighs the “minuscule” risk that the new span would weaken or fail without fully functionin­g shear keys.

“The likelihood that a big earthquake will come between now and the time a recent interview. “It is a risk worth taking compared to keeping traffic on the old bridge.”

Nearly every engineer who has studied the existing 77- year- old bridge predicts and motorists will not see during Monday’s briefi ng is a written seismic safety assessment from the Federal Highway Administra­tion or the independen­t panel convened by the Legislativ­e

“The likelihood that a big earthquake will come between now and the time that the bolts are fixed is a very small exposure window when compared to the 150- year life span of the bridge. It is a risk worth taking compared to keeping traffic on the old bridge.”

that the bolts are fi xed is a very small exposure window when compared to the 150- year life span of the bridge,” said panel Chairman Frieder Seible during it will suffer a catastroph­ic failure when the next big temblor strikes the adjacent Hayward or San Andreas faults.

What elected offi cials Analyst’s Offi ce to review the bridge foundation and the bolts. Those will come later, perhaps in August.

The Toll Bridge Oversight Committee — the executive directors of Caltrans, Metropolit­an Transporta­tion Commission and California Transporta­tion Commission — requested in May a federal review of its approach to the bolt failure.

An agency representa­tive may deliver a verbal status report next week, but the full reports won’t be ready until after the team submits the long- term corrosion testing results and a maintenanc­e plan, Caltrans Deputy Director Rick Land said. Contact Lisa Vorderbrue­ggen at 925- 9454773, lvorderbru­eggen@bayareanew­sgroup.com, politicswi­thlisav. blogspot. com or Twitter.com/ lvorderbru­eggen.

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