If a massive earthquake ever hits the city of San Francisco, the resulting disaster could be even worse than the devastation wrought by Hurricane Katrina on the city of New Orleans.
The picturesque California city could be faced with the task of evacuating as many as 2 million people by sea if an earthquake buckled roads and brought down buildings and bridges.
"If I don't have a Bay Bridge and a Golden Gate Bridge, we're in essence an island," said the city's mayor, Gavin Newsom.
A serious earthquake could break gas lines, leading to massive fires. There might be no way to fight the fires if water lines were also broken.
Even worse, most of the city's police and firefighters live outside the city and would not be able to get in over broken bridges. Emergency communications would have to come from a system of quake-proof World War II sirens situated around the city.
Newsom says Katrina radically changed his approach to disaster preparedness. "I'm not thinking just outside the box. We're blowing up the box," he said.
Newsom's car can function as a mobile command center, complete with all emergency communication equipment. City Hall sits on rollers designed to withstand an earthquake. And in the event of a quake, Newsom says, civil servants would be pressed into a dual role.
"We have 30,000 city employees, all of them can be conscripted in the context of an emergency," he said. "We've reminded all our employees they have an obligation -- a real obligation -- to participate in disaster scenario plans and to participate in evacuation plans."
In October 1989, San Francisco received a hint of what could come when a magnitude 7.1 tremor hit 60 miles south of the city, leaving 4,000 injured and 63 dead. Part of a freeway collapsed, and property damage totaled $6 billion.
Mary Lou Zoback, a seismologist with the U.S. Geological Survey, says some of the problems that existed in 1989 still exist today.
"Most of the building stock in San Francisco, particularly the residential housing, was built prior to ... 1960," she said. "Something like 75 percent of it."
Those buildings are less resilient than newer structures and likely to be severely damaged or destroyed in the event of a major earthquake.
If the buildings are destroyed, their gas and water lines could also be ruptured, making the likelihood of a fire "very substantial," Zoback said.
Experts say many critical structures in the city may also not have been adequately upgraded to withstand earthquakes, including:
• the city's biggest hospital, San Francisco General, where many of the injured would be taken;
• the Bay Bridge connecting Oakland and San Francisco;
• and nearly a third of the city's schools.
Newsom concedes: "Everything needs to be reviewed." He noted that when the city suffered an electrical explosion in August, one of the city's mobile command centers was working with maps from 1985.
"Frankly, a lot of us have gotten our eye off the ball and focused almost exclusively on man-made disasters, and the lexicon of homeland security," Newsom said
"We've got a lot of work to do in this country on that but we've also got to get back to the basics ... that means looking at Mother Nature -- be it tornadoes and hurricanes, [and] obviously to the issues of earthquakes," Newsom said.
A major earthquake in the Bay Area should not just concern San Francisco residents. The effects of such a disaster could extend throughout California.
A system of levees keeps San Francisco Bay's salt water from farmland and vital fresh water supplies -- which provide drinking water for some 20 million Californians all the way down to Los Angeles and San Diego. Many of the levees are already in serious disrepair, and in the event of a large earthquake, many could be expected to break.
A major quake on the Hayward fault in the East Bay could affect a 1,000-mile levee system and cause Katrina-level flooding for hundreds of miles, experts warn. Last year, one levee broke and 12,000 acres flooded.
However, a major earthquake researcher says California and the federal government are woefully unprepared for such an event.
"The state of California does not have one person in the Office of Emergency Services who is a full-time earthquake person, studying earthquakes, preparing responses," said Susan Tubbesing, director of the Earthquake Engineering Research Institute.
She said the staff at the Federal Emergency Management Agency has also been drastically downsized. "There used to be 30 or 40 people on that part of FEMA, and today I think maybe there's five or six. And that's for the whole country," she said.
Despite all the warnings, a third of all Californians say they are not prepared for an earthquake. There are hopes those numbers will fall, in light of what Newsom says is a sad reality.
"I don't think I should be the one saying it, because I don't feel comfortable saying it," he said. "But you're on your own."
"The federal government's not going to come in and save the day within 24 minutes, let alone 24 hours," he said. "If we have an 8.2, 8.3 earthquake in San Francisco, people are going to need to be prepared for a minimum of 72 hours on their own."
The people of San Francisco are now just months away from an ominous 100-year anniversary. In April 1906, a magnitude-8.0 quake shook the city for one minute and left some 3,000 people dead and more than a quarter million others homeless.
Now more than ever, San Franciscans are looking back, and wondering what comes next.