Will Quake Warning Leave Californians Shaking? : Safety: Alarm system could be in place within 10 years. It would give people perhaps 30 seconds to prepare. But some experts say panic could cause more deaths and injuries.

Dec. 9, 2004, at 10:37 a.m., a section of the San Andreas Fault in central California gives way under decades of built-up stress, sending deadly shock waves toward Los Angeles and San Francisco.

The destructive S-wave will hit the urban centers in 25 seconds--but thanks to a recently completed early-warning system, the cities won’t be caught by surprise.

In the first second, the four newly installed U.S. Geological Survey sensors closest to the epicenter pick up the first waves and beam warning signals at the speed of light to receivers in the two cities.

Two seconds: Emergency Broadcasting Systems receive the signal and cut into radio and television programming with: “Your area is about to be hit by a strong earthquake. . . .”

Three seconds: An earthquake alarm rings in Los Angeles schools, sending 700,000 children under desks, away from windows or onto designated sections of the schoolyard.

Four seconds: San Francisco Fire Department doors automatically open and firefighters rush to get equipment outside before it can be crushed or blocked.

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Five seconds: Elevators at Southern California Edison Co. headquarters in Los Angeles automatically stop at the nearest floor and their doors open.

Six seconds: Bay Area Rapid Transit trains reroute for the nearest station and glide to a stop.

Seven seconds: An alarm ringing at Stanford Medical Center warns doctors to protect and stabilize surgery patients, nurses to place weak patients in a lying or sitting position.

Eight seconds: Red warning lights flash on the Golden Gate and San Francisco-Oakland Bay bridges, alerting approaching motorists to stay off . . .

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This is how an earthquake alarm system should work.

And to some degree, such a system is now in place for Mexico City, where it was triggered by a powerful quake on Sept. 14.

But setting up a seismic warning system in fault-riddled California is far more complex, experts say, and fraught with risks, especially in the case of false alarms. But most expect some sort of quake-alert plan to become a reality in the state within a decade.

“Clearly, a system that does provide even a few seconds of warning would be useful,” says Richard Andrews, head of the state Office of Emergency Services. “And it will be potentially the most valuable in the largest and most destructive events.”

Andrews cautions, however, that the alarm system will only work for communities that lie some distance from the epicenter.

A city right over the rupture--such as Oakland in the case of a Hayward Fault quake or many parts of Los Angeles--would have no effective warning.

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Caltech seismologist Thomas Heaton noted that the last great Southern California quake, the magnitude-8.3 Ft. Tejon temblor of 1857, apparently started near the tiny town of Parkfield, about halfway between Los Angeles and San Francisco on the San Andreas Fault.

“There would have been over a minute between when it struck and when L.A. got its maximum shaking, so in that kind of situation, you could give a warning,” Heaton said. Compare that to the Jan. 17, 1994, Northridge quake, where “the epicenter was closer to the city. You couldn’t get more than a couple of seconds at best.”

Scientists see an advance warning system as the natural outgrowth of high-speed seismic sensor networks now being established around the state to provide instant data during a quake for use by emergency workers.

“You can do it with the same sensors and same computer equipment,” said Michael Reichle, supervising geologist with the California Division of Mines and Geology.

The state Office of Emergency Services has a $20-million proposal before the Federal Emergency Management Agency to install 600 upgraded sensors in Southern California with some of the Northridge quake recovery funds.

The U.S. Geological Survey says that with $10 million to $15 million, it could do the same in Northern California.

The UC Berkeley Seismographic Station has just received $85,000 from Pacific Bell to upgrade its sensor communication lines for an instant quake analysis system.

State geologist Jim Davis says both instant analysis and advance warning systems push “the technological envelope” of a seismic monitoring network.

The challenge would be processing and interpreting data fast enough to issue a warning signal while the ground is still shaking.

This would get electrical impulses moving out ahead of the slower destructive seismic waves to trigger warnings in distant populated areas.

“It might say something like, ‘Light shaking in five seconds; enjoy it,’ ” Heaton quipped. “Most times, it would come on and say, ‘Don’t have a cow.’ ”

Special alarm systems might also be installed in schools, offices and other locations, but this could be costly.

Los Angeles Unified School District spokesman Patrick Spencer says the schools want the system--if they can afford it.

“It would be a life-saver,” he says. “There are emergency plans for every school, but we have no capacity now for advance warning.”

The Los Angeles district alone has 10,000 classrooms, Spencer notes, and all districts are suffering through an era of tight budgets and cost reductions.

Fire departments and hospitals are among the strongest supporters of the early alarm system.

“For our units, that 20 or 30 seconds could be real critical,” says San Francisco Fire Department disaster coordinator Frank Lucier. “When the earthquake hits, we open the doors and pull out all our apparatus.”

Dave Johns, engineering supervisor for Southern California Edison Co., which serves 4.1 million customers, says protecting employees would be the biggest benefit for the utility.

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But there are no plans, he says, to turn off electricity in advance of the quake. The utility fears it would create more problems than it would solve--and turning off power for false alarms could generate a flurry of lawsuits.

Pacific Gas & Electric Co.’s senior seismologist, Woody Savage, has worked closely with the U.S. Geological Survey on the new sensor system and agrees that shutting down gas or electricity isn’t an option.

“We’d be probably better off keeping everything running,” he says. “The process of relighting the pilot lights is a big problem. Customers may very well be more at risk.”

Perhaps most skeptical of the early warning plan is CalTrans, the state department of transportation. Spokesman Jim Drago rejects automatic warning lights or barriers to keep drivers off the Golden Gate Bridge or elevated highways, in part because they send the wrong message.

“What you are saying is that this bridge would not be able to withstand the maximum credible earthquake,” Drago said.

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And the Office of Emergency Services acknowledges that a warning to the general public might create panic that could cause more deaths and injuries than the quake itself.

Andrews, head of the state agency, says whatever alarm system is eventually built, it will only work if the public is educated on what to do--and what not to do--when that alarm goes off.

“It has a very strong endorsement from OES,” he says. “But there are a number of issues that would really have to be thought through.”