Quake Most Costly U.S. Disaster

Roughly one in every three dollars of damage from the Northridge earthquake went unreimbursed, according to new, sharply higher official estimates of the quake’s cost that would rank the temblor as the most expensive natural disaster in U.S. history.

Previously, officials have estimated the cost of the quake at $30 billion, but the new estimate, released Wednesday by the state’s top disaster official, puts the damage at $40 billion to $42 billion.

That estimate easily moves the 1994 earthquake past Hurricane Andrew in 1992, where damage ran about $30 billion. Japan’s Kobe earthquake of 1995 holds the world damage record--about $100 billion using 1995 exchange rates.

Insurance payouts for Northridge have been put by industry sources at $12.5 billion, and government aid came to more than $13 billion, according to White House estimates. So the new estimate of the total cost of the quake would indicate that private and public assistance covered about two-thirds of the cost of the disaster.

Richard Andrews, director of the governor’s Office of Emergency Services, told a Pasadena conference that his updated figures on Northridge damage rely on new insurance industry studies and include such “indirect” quake losses as unemployment and worker’s compensation payments.

The main subject of the conference, sponsored by the quake modeling firm EQE International, was new technology, including a more comprehensive network of seismographic stations that would provide very quick estimates of what has been damaged and where.

The new technologies should allow preliminary damage estimates within minutes. By contrast, the state’s new estimate of Northridge damage has taken three years.

Andrews noted that the first official damage estimate for Northridge was reached by his agency about 12 hours after the earthquake. It put costs at $15 billion to $18 billion.

However, he said, engineers who were sent out to make assessments in the days after the quake soon reported back to the emergency services office that “we’re seeing a lot of damage we didn’t expect.”

Accordingly, he said, when the Wilson administration wrote to President Clinton asking for federal assistance, the state estimated the damage at $30 billion or more.

Estimates of injuries from the quake have also moved upward. State officials had put the toll at 57 deaths and 9,000 injuries, but a well-researched estimate done by a Woodland Hills public health expert in 1995 put deaths at 72 and injuries at 11,846.

Other speakers at the conference said that when the new Tri-Net seismic network of 600 stations is fully computerized and the Global Positioning System is further developed, perhaps in about five years, quake information will be much quicker in coming than it has been.

Jim Mori, scientist-in-charge of the Pasadena field office of the U.S. Geological Survey, said the goal is to provide a notification of strong shaking within 15 seconds of the onset of a big quake.

The goals also are to give a location and preliminary magnitude of a quake within 30 seconds. Within 50 seconds of the quake onset, the first information about ground motion should be available.

Within three minutes, there should be a definite quake magnitude and the first preliminary maps of the shaking intensities at various spots, Mori said.

Fault rupture parameters and a complex map of the shaking intensities would be ready, according to the goals, 30 minutes after the shaking began.

In the 1995 Kobe earthquake, authorities did not announce final shaking intensities for three days, Mori said.

In a keynote luncheon speech, Caltech engineering seismology professor Thomas H. Heaton struck a cautionary note. He observed that the planned seismic network of 600 stations is not yet fully funded.

A highlight of the conference was a demonstration by EQE Vice President Ronald Eguchi of a new system the firm has developed called EPEDAT, or Early Post Earthquake Damage Assessment Tool.

Although Eguchi gave no precise time estimate, the system would very quickly provide authorities with maps showing shaking intensities, probable damage to key facilities and other information.

He said, however, that the system will not be fully operational until the seismic network is complete.