Coachella Valley after the "Big One": Be prepared for isolation
Keith Matheny • The Desert Sun • May 22, 2008
The findings of a new scientific study looking at the effects of a major earthquake in the region should send a clear message to Coachella Valley residents, local officials said -- being self-prepared and helping your neighbor would be a necessity.
"We very definitely will be cut off," said John Hardcastle, the city of Palm Springs' emergency services director.
"We're going to have to rely on each other. People will have to be self-reliant. We can't wait around on somebody else."
Added Desert Water Agency general manager Dave Luker, "I think the Coachella Valley would be on its own for a while. We need to look at it that way and approach it in a fashion where we can exist -- maybe not as we would like, but at least exist."
In a terrifying but all-too-real scenario that scientists unveiled today, "The Big One," a magnitude 7.8 earthquake on the dangerous San Andreas Fault, rips from the Salton Sea through the Coachella Valley, devastating much of Southern California.
Hundreds die. Buildings crumble. Fires rage. Highways are unnavigatable. Rail lines and water and sewer pipes are broken. Hospitals are swamped with 50,000 injured people.
All told, such a quake would create a regional disaster on par with Hurricane Katrina - $200 billion in damage to the economy and 1,800 dead, experts said.
About 700 of the dead are victims of building collapses. Many die in the 1,600 fires burning across the region - too many for firefighters to tackle at once.
The major quake called for in the scenario is about 150 years overdue on the portion of the San Andreas that runs through the Coachella Valley, based on historic intervals.
Though the effects of such a quake, starting near the Salton Sea, could be significant as far away as Bakersfield, the Coachella Valley would be among the hardest-hit areas, officials said.
"The shaking in the Coachella Valley is especially intense, even prolonged because of the deep basin that is there," said U.S. Geological Survey geophysicist Ken Hudnut.
The valley would experience more than 30 seconds of "damaging shaking," he said.
"That really is the start of the severe damage to Southern California," he said.
In addition to fallen buildings from the shaking, areas around the Salton Sea and northward toward southern Indio are expected to experience liquefaction, a loosening and collapse of the ground, said Dan Ponti of U.S. Geological Survey, who helped develop the earthquake scenario.
"The southern part of the Coachella Valley is probably the one place in Southern California that will suffer the most damage from liquefaction effects," he said.
"That whole area is subject to ground-sinking." It would have a significant impact on buildings in the area, Ponti added, though noting that much of the area is agricultural.
Researchers caution that the report is not a prediction, but that the possibility of a major California quake in the next few decades is very real.
"It will happen eventually; you can count on it. We just don't know when," said Rancho Mirage resident Dennis Mileti, who participated in the study.
Mileti is a professor emeritus from the University of Colorado, a member of the California Seismic Safety Commission and one of the nation's leading scientists on the social science and policy aspects of disasters.
A team of 300 scientists, governments, first responders and industries worked for more than a year to create a realistic scenario that can be used for preparedness, including a statewide drill planned later this year.
Published by U.S. Geological Survey and California Geological Survey, the report will be released today in Washington, D.C., before a House subcommittee.
Rancho Mirage resident Carol Granger was aware the earthquake scenario was on its way and said it's a good thing to have.
"(Experts are) actually going to know what could happen in the area, and that's a huge advantage," she said following Wednesday's city Emergency Preparedness Commission meeting.
Commission Chairman Dick Perry called the scenario "very plausible," and said he was impressed with the level of details it provided. "None of it seemed outlandish to me; it was very realistic," he said.
"I think one of the great values of an exercise like this is that it points out all the areas that are going to be major concerns, and all of the things that aren't so obvious."
Starts at Salton Sea
The envisioned earthquake would last three minutes - 15 times longer than the disastrous 1994 Northridge quake, which was much smaller at 6.7.
"We cannot keep planning for Northridge," USGS seismologist Lucy Jones said. "The science tells us it's not the worst we're going to face."
Starting near the Salton Sea, the quake in the scenario would send shock waves moving at 2 miles per second.
Though Mileti was well-versed in disaster and major earthquake scenarios going into the project, some of its findings surprised him, he said.
"Fire is probably going to cause more damage than the earthquake," he said.
The scenario projects 1,600 fires destroying 200 million square feet of housing, with damage at $40 billion to $100 billion.
"There would be firestorms that we call conflagrations," Mileti said. "There aren't that many fire engines."
The damage to water infrastructure will be catastrophic.
"So many water pipes will break, there aren't enough water pipes in the country to replace them," Mileti said.
From the Coachella Valley to Los Angeles, entire water delivery systems may need replaced, he said.
The Coachella Valley's recovery time on water delivery would likely be shorter because of its use of well water, Mileti said.
Some of the surprising news to Mileti was good, he said.
"Parts of the Coachella Valley, even though we're going to shake quite a bit for a long time, will still be functional," he said. Much of Eisenhower Medical Center will survive without significant damage, Mileti cited as an example.
Staff writer Colin Atagi contributed to this report.
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