Study Foresees More Deadly Quake Toll : Disasters: Researchers now say that a magnitude 7.0 temblor on the Newport-Inglewood Fault would cause up to 8,000 fatalities and $220 billion in losses.
Researchers have increased their estimates of losses from a prospective magnitude 7.0 earthquake on the Newport-Inglewood Fault in Los Angeles and Orange counties, substantially raising the predicted number of deaths and the amount of damages.
Instead of the previously estimated 2,000 to 5,000 deaths released last year, the researchers from Stanford University and the quake mitigation firm of Risk Management Solutions now see 3,000 to 8,000 fatalities. And instead of economic losses of $125 billion to $145 billion, they see $175 billion to $220 billion in losses.
The researchers say injuries would be as high as 20,000, up from the 15,000 cited in the preliminary version.
The numbers were revised in the wake of January’s Kobe earthquake in Japan, as well as the 1994 Northridge temblor and new estimates provided by the insurance industry of local building inventories, said Haresh Shah, Stanford professor of structural engineering.
The new uppermost damage figure is more than eight times that for the Northridge earthquake, which at magnitude 6.7 was less than half as strong as a magnitude 7.0, and was centered under a less densely populated area.
Although the researchers said 82% of the economic loss would be in Los Angeles County and 15% in Orange County (plus 3% in other counties), the Orange County losses alone could reach $33 billion, or about $6 billion more than Northridge.
The Newport-Inglewood Fault extends 33 miles from Newport Beach through North Long Beach to Culver City. Because it passes through such a heavily populated area, the researchers believe that a 7.0 earthquake would be the most damaging conceivable quake that could occur in Southern California.
Quake probabilities assigned by scientists last year for the next 30 years are about six times greater in the San Bernardino area than along the Newport-Inglewood Fault. But Shah said they designed their study to be a worst-case quake scenario, where the damage would be greatest.
The researchers estimate the recurrence interval for a magnitude 7.0 earthquake on the fault at 340 years. The last strong quake on the fault was the 1933 Long Beach temblor, seven times smaller at 6.3, which killed 120 people and caused several hundred million dollars in damage, according to current dollar values.
The new damage figures point out why the insurance industry and the U.S. government are increasingly fearful that a monumental disaster could stretch or exhaust public and private resources.
Since 1989, according to figures supplied by the federal Office of Management and Budget and the insurance industry, relief expenditures on hurricanes Hugo, Andrew and Iniki, the Loma Prieta and Northridge earthquakes and the Midwest floods have cost about $66 billion total. The breakdown is $33.7 billion for the federal government and $32.2 billion for the insurance industry.
Yet these figures would be dwarfed if the Newport-Inglewood quake foreseen in the new scenario were to occur. The researchers estimate that insurance industry payouts alone would be between $95 billion and $120 billion.
Yet, Shah said Wednesday in an interview, the damage figures could be cut substantially if Southern California pursued a much more aggressive program of retrofitting and other quake mitigation.
“What we need to do is to restrict building in certain areas with land-use controls or monetary penalties for building, and, second, we should retrofit everything, commercial buildings, residential buildings, our bridges, our water supply lines,” the Stanford engineer said.
“But none of this will work unless and until our society can come up with some kind of incentives to do this . . . maybe tax write-offs, a reduction of insurance rates or a reduction of mortgage rates, for those who do it, or a combination of all of these,” he said.
The 85-page research report said economic losses would be between $65 billion and $85 billion for commercial properties, inventories and equipment; between $60 billion and $75 billion for residential property and contents; between $30 billion and $35 billion for business interruption and additional living expenses; between $8 billion and $14 billion for freeways, power lines and other lifelines, and between $11.2 billion and $13.5 billion for other things, such as general liability, workers’ compensation, life insurance claims, medical expenses and toxic cleanup.