Southern California stages biggest U.S. quake drill

LOS ANGELES (Reuters) - Millions of Southern Californians simultaneously dropped to the floor and huddled under tables and desks for two minutes of imagined seismic turmoil on Thursday in the biggest U.S. earthquake drill.

The Great Southern California ShakeOut was organized by scientists and emergency officials as part of a campaign to prepare the region's 22 million inhabitants for a catastrophic quake that experts say is inevitable and long overdue.

The drill was based on the premise of a magnitude 7.8 quake striking the southern portion of the famed San Andreas Fault, a subterranean chasm between two massive plates of the Earth's crust that extends hundreds of miles (km) across the state.

The hypothetical quake, similar in strength to the devastating tremor that hit China in May, also is the basis for this year's Golden Guardian exercise -- a days-long annual disaster simulation for emergency-response agencies statewide.

"This helps us hone our skills," said Patricia Aidem, a spokeswoman for Providence Holy Cross Medical Center in suburban Los Angeles, whose trauma center took part in a mass-casualty drill.

"We live in earthquake country, so being prepared to help the public is just an amazing advantage for the community."

Teaching quake survival skills to often-complacent Southern Californians also "means fewer patients for us," she added.

At the Nestle USA headquarters in Glendale, just north of Los Angeles, all 1,600 employees in the 21-floor office tower took part in the ShakeOut.

Sales associate Jared Bogda, 25, admitted afterward he felt "a little silly" but insisted the exercise was worthwhile.

"Being from the East Coast, it was a change for me," he said. "At first I thought 'Oh, this is really ridiculous' ... But you know what? You've got to do what you've got to do."

MILLIONS REGISTER

More than 5.3 million people -- about a quarter of Southern California's population -- signed up for the drill, including entire school districts and college campuses. Organizers said many more joined in without registering.

Organizers said they were aware of only one such exercise on a bigger scale -- a drill for 8 million school children in South Korea about six months ago. Japan also holds large-scale quake drills every year.

Thursday's event began at precisely 10 a.m. PST (1800 GMT), with people in classrooms, offices and homes asked to perform the "drop, cover and hold-on" exercise for two minutes.

In a variation of the "duck and cover" nuclear drills of the Cold War era, participants were told to hit the floor and crawl under a sturdy piece of furniture, folding their arms over their heads and necks until the shaking stops.

Some were guided by a pre-recorded public service message, accompanied by sounds of a rumbling quake, distributed in advance and played over the airwaves by radio and TV stations.

The quake scenario devised by geophysicists and engineers envisioned a calamity that would leave 1,800 people dead, 50,000 injured and 250,000 homeless.

It would topple 1,500 buildings, badly damage another 300,000 and sever highways, power lines, pipelines, railroads, communications networks and aqueducts. Property losses of over $200 billion were projected.

The quake also would ignite about 1,600 fires, some turning into blazes engulfing hundreds of city blocks. Experts predicted the biggest long-term economic disruption would come from damage to water-distribution systems that would leave some homes and business without running water for months.

A rupture of the San Andreas Fault in Northern California caused the massive 8.3-magnitude quake that laid waste to San Francisco in 1906.

The last "big one" to strike south of the San Gabriel Mountains, near Los Angeles, was 300 years ago. The average interval between such quakes in that region is 150 years.

The biggest Southern California temblor in recent years, the 6.7-magnitude Northridge quake in 1994, killed 57 people and caused about $40 billion in damage.

(Editing by Dan Whitcomb and John O'Callaghan)