SAN DIEGO —— They have no formalized plan to handle it. But law enforcement, county emergency services and state transportation officials said Friday that they could conduct a mass evacuation of San Diego County's 3.1 million residents —— efficiently turning incoming Interstates 5, 15 and 8 into outbound pathways from the county "in a matter of hours."

"It doesn't require a lot of preparation for that," said Officer Tom Kerns of the California Highway Patrol. "It only takes one officer to block off an entire freeway. Think about it, traffic cones, Caltrans (California Department of Transportation) crews."

Officials said they have evacuation plans for various San Diego County communities and those surrounding, dams and the San Onofre Nuclear Generating Station. And 10 of an estimated 40 evacuation plans for unincorporated communities have already been created, with another 10 expected to be finished by the end of the year.

But they said there is no overarching written plan to handle an evacuation of the entire county, such as the one unfolding in Houston and other parts of the Gulf Coast —— because San Diego County doesn't have the kinds of disasters that would require or allow such an evacuation.

Quakes, fires, tsunamis

"The sorts of things that frighten us are wildfires, earthquakes and the potential for tsunamis," said Capt. Glenn Revelle of the San Diego County Sheriff's Department —— the agency along with city police departments that would call for any evacuations.

Revelle and others said Friday that earthquakes, wildfires and tsunamis would not require the all-county evacuations that people are watching on television in Texas because they either occur without advanced warning, or are "limited in scope."

Unlike hurricanes, which often take days to reach populated areas and give people the chance to flee, there no warnings for earthquakes.

When a quake —— such as the devastating 1994 Northridge earthquake which caused $29 billion in damage in California —— hits, people and law enforcement officials respond. Instead of evacuating, victims are most often advised to "hunker down" and stay put. And emergency responders end up trying to work their way into communities to find and treat people.

Tsunamis, or tidal waves, and wildfires, meanwhile, typically would never be large enough to require the entire county to flee, officials said.

The 2003 wildfires that killed 16 people and destroyed 2,400 homes forced tens of thousands of San Diego County residents to evacuate —— as opposed to the millions that have been sent packing by hurricanes Katrina and Rita in New Orleans and Texas.

Asked about terrorist attacks, which could include nuclear or "dirty" radiation bombs, Revelle said even those attacks would likely be limited in the size of their devastation, and not require a massive evacuation.

"We plan for worst case (situations)," Revelle said. "But it's difficult to fathom something like Texas is seeing now."

Smaller plans

However, Revelle said that the Sheriff's Department, which serves the unincorporated county and nine cities, does have plans that divide the county's 4,261 square miles into several sections, and there are individual evacuation plans for the sections.

County of San Diego officials said a full-scale evacuation of the county could be conducted by staggering evacuations of the county's sections.

Meanwhile, Susan Asturias, a senior emergency services coordinator with the county's Office of Emergency Services, said there are specific evacuation plans for areas surrounding all the dams and reservoirs in the county. They come with flooding pathways, lists of institutions in the flood areas, identified evacuation routes and lists of confidential phone numbers of people the county would notify.

County officials have also been working with unincorporated communities since the 2003 fires to create individual evacuation plans. County spokesman Mike Workman said the county expects to have 20 of roughly 40 community plans finished by the end of the year.

Officials from the San Onofre Nuclear Generating Station have had detailed evacuation plans for many years. However, they said that evacuation in the event of a problem at the plant would still be limited. A radiation leak, accidental or caused by an attack, would only affect residents living within a 10-mile radius, officials say. Oceanside, the closest North County community, is 14 miles away. Plant officials have said it would be "impossible" for the plant to explode like an atomic bomb, although some critics worry about reactor meltdowns or spent-fuel piles.

Exit quickly?

Revelle said that unlike in Houston, where it took officials an entire day to convert inbound freeway lanes into additional outbound lanes, Interstates 5, 15 and 8 could quickly be turned into one-way escape routes.

"That could be done in a matter of hours," Revelle said. "That's our plan. All they (Highway Patrol) would have to do is stop traffic, and all our agencies would come together to block off (some) freeway entrances."

California Department of Transportation officials said they have 400 maintenance employees in the county, 80 of whom are emergency "first responders" who could also help with freeway traffic management.

Highway Patrol officials said they would work with the media, the state transportation department, and through aerial surveillance to coordinate a mass exodus.

Single lanes to allow traffic coming into San Diego County would likely be left open so that medical support and supplies could be brought from outside the county to help those trying to get out.

However, there is no guarantee as to just how smoothly any massive evacuation would work, and whether it would be any more effective than in Texas, where panicky evacuees jumped on freeways at the same time, jamming roads.

"We haven't ever done a study," Asturias said. "I think it's doable. But who knows how long it would take?"

Herman Reddick, assistant director for the county's Office of Emergency Services, said it depends upon the public.

"As long as citizens follow the directions given by public safety personnel, it should be able to be accomplished efficiently," he said. "If they don't follow the directions provided, then you get into situations where it would not be as efficient as it could be."

Contact staff writer Gig Conaughton at (760) 739-6696 or gconaughton@nctimes.com.