If a similar magnitude 7.9 earthquake hit San Francisco as it did in 1906, the damage would be on the magnitude of hurricanes Katrina and Rita.

"There will be mass casualties. There will be losses of businesses and institutions," Rich Eisner, coastal region chief for the California Office of Emergency Services, said in a briefing Thursday for East Bay emergency managers. "Nobody will be safe."

Eisner said damages from such a earthquake are estimated at $122 billion, close to the costs of hurricanes Katrina and Rita that his the U.S. Gulf Coast last year, the Oakland (Calif.) Tribune reported Friday.

A high magnitude earthquake would effectively make the Bay Area an island, since all highways and bridges would likely be impassable, its hospitals overwhelmed and outside help beyond reach because of fires, Eisner said.

"It is comparable to the worst natural disaster in American history," he said.

Copyright 2006 by United Press International