Southern California Braces for the Big One During Earthquake Drill

ShakeOut prepares residents for biggest quake in 100 years.

by / November 14, 2008

At 10 a.m. on Nov. 13, 2008, Southern California experiences a shaking unlike anything felt in the region in more than 100 years. A magnitude 7.8 earthquake has hit the southern San Andreas Fault near Salton Sea and impacted Imperial, Kern, Los Angeles, Orange, Riverside, San Bernardino, San Diego and Ventura counties.

The quake and its aftershocks produce between 10,000 and 100,000 landslides. Fires erupt across the region. Five high-rise buildings in Los Angeles collapse. Roads, railroads and utilities that cross the fault are ruptured. The worst damage is where the shaking is the strongest and longest, in the Riverside and San Bernardino areas. Emergency responders have to cope with chemical spills and the potential of dam ruptures. Overall, the region suffers 1,800 deaths and more than $200 billion in economic losses.

How ready are the public, first responders and emergency management officials to deal with such a scenario? That's one of the questions regional officials hoped to answer with drills it ran earlier this week. Based on this scenario, both the Golden Guardian emergency response exercise and the Great Southern California ShakeOut -- a drill for members of the public -- were designed to test California's capability to respond and recover during a catastrophic earthquake.

The first thing emergency management officials should realize about a quake of that magnitude is that initially they will be dramatically overwhelmed, said Dennis Mileti, a member of the California Seismic Safety Commission.

"This quake [would] be unlike any drastic emergency anyone has experienced or can remember," said Mileti, professor emeritus in sociology at the University of Colorado and an expert on the societal aspects of hazards and disasters. "It is a class apart. That has ramifications for public information, sheltering, food and water, fire suppression --everything flows from that."

Mileti pointed out that because it is so well practiced, California's emergency response community is among the best in the country. When they are overwhelmed in a normal emergency response, such as during huge fires, unaffected neighboring communities help in mutual aid pacts. However, in this quake scenario, that didn't happen right away, he said. For Riverside and San Bernardino counties, for instance, there wouldn't be any way for other responders to get there.

"Riverside County will be ripped in half," he said. The I-10 freeway sits on top of the fault in many places, and it would be torn in half. Airports would not be functioning initially. So local emergency response teams in towns and villages, such as Rancho Mirage, where Mileti lives, would be on their own. "That doesn't mean they won't work tremendously hard," he said, "but the demand will be way beyond their capacity."

What that means is that non-emergency response individuals will play an important role. "The real first responders are victims," he said. Studies of previous large earthquakes have found that 95 percent of people rescued were saved by other victims, not by search-and-rescue teams or firefighters.

Emergency responders would get some things up and running in about a week, but until then, the citizenry is on its own for basics like food and water.


Creating the Scenario

The ShakeOut scenario was the first public product of the U.S. Geological Survey (USGS) Multi-Hazards Demonstration Project. ShakeOut brought together 300 seismologists, engineers, social scientists and computer experts from around the world to make projections to help Southern California improve its resiliency to natural disasters through improved planning, mitigation and response.

Why did they pick the southern part of the San Andreas? That section

of the fault has had a quake on average every 150 years, yet it hasn't moved for 300 years. "Many seismologists think it is 10 months pregnant," said the USGS's Dale Alan Cox, the project's manager.

One goal of the demonstration project was to help emergency management officials prepare to respond.

"We asked emergency management officials what tools they need," said Cox. "They asked us what it would mean to have an earthquake of this magnitude, because all they have to go on is earthquakes of the past, such as the Northridge earthquake of 1994, which was much smaller [6.7 magnitude]. It lasted only 18 seconds. This quake is projected to last three minutes."

For emergency managers and fire departments, goals of the Golden Guardian exercise included getting the drill into muscle memory and uncovering some previously unknown vulnerabilities, Cox said. The first question they must address is how to get to people needing assistance, because traffic wouldn't be moving and many bridges would be out.

"We are dealing with a large population that is transportation-challenged," explained Henry Renteria, director of the California Governor's Office of Emergency Services. "It's too dependent on autos, with not enough public transit. So part of the scenario is how to move supplies and emergency personnel if the freeways are impassable; how to get first responders in and out. This will give us a scenario to test other systems for doing that, moving people by waterways and by helicopter if airport runways are damaged."


Fire Worries

The secondary hazard that most immediately concerns emergency managers is fire. Extrapolating from previous earthquakes, experts predict that 1,600 fires would start, of which 1,200 would be too large to be controlled by one fire engine company. It's estimated that 133,000 homes would be lost.

"In areas of dense wood-frame construction, these fires if not controlled will grow quickly to involve tens or hundreds of city blocks," the scenario predicts.

For the Los Angeles area, in particular, there would be so many fires that there'd be no way to put them out before they merge into a major conflagration.

According to Mileti, the scenario projects that almost every water pipe in the Los Angeles area would break. "The damage is going to be so extensive that the water companies are going to determine that it is cheaper and easier to replace the entire system rather than fix it," he added. "It will be six months before you will be able to turn the tap back on."

"Fire chiefs tell us that water is to firemen what bullets are to police," Cox said. "Well, with so many pipes breaking during the quake, there isn't going to be water to fight the fires."

Renteria, who worked in emergency management in Oakland during the 7.1 Loma Prieta quake in 1989, noted that in the 1906 San Francisco earthquake, it was fire - and the lack of water to fight the fire - that destroyed so much of the city. That's why San Francisco is the only U.S. city with an underground cistern system to store water, he said.

He said fire departments are adding tools to get water to where it is needed, including above-ground hydrant systems on trucks that can pump water out of a lake, river or even the ocean.

"What keeps me awake at night is the weather after a quake," Renteria said. "If it comes in September or October, the time of strong Santa Ana winds, that would be the worst-case scenario."

Mileti said the Shakeout scenario poses difficult questions about fire response. "How do you manage in a situation like that? There may not be an answer."


David Raths contributing writer