Responders prepare for big quake in Calif.

LOS ANGELES But that's not all. Federal and state emergency management agencies have put together their biggest plan yet to deal with a catastrophic quake.

Elementary steps for earthquake preparation are on the way to becoming more complex and more widespread.

For the last two years geologists and responders have examined past quakes and what could happen in a catastrophic /*Southern California*/ temblor 7.8 or larger.

It would mean more than a few communities impacted. Instead, a whole region could be paralyzed.

"The roads being down, the rails being down, the airports being closed. It's harder to get to the people that need our help," said Justin Dombrowski of FEMA.

Emergency planners and responders from throughout Southern California are now joined with /*FEMA*/ to prepare for a worst case scenario. Collapsed buildings may be the least of it.

"The real shocker to me was the impact on infrastructure. What I mean is your water system. We are talking, not a couple of hours or a day, we're talking, in some places, days and maybe even weeks before we could get those systems back in place," said Steven Sellers of California Emergency Management Agency.

The problem with bottled water is that it's heavy and bulky and you're going to need a lot of it. After an earthquake, roads may be impassable, making it hard for responders to get bottled water to residents.

The recent contamination emergency in Barstow gives a glimpse of what could happen. There was also the Baja quake which inflicted critical damage 35 miles away in the Imperial Valley.

"In Imperial, we had water clarifiers for the water district that were knocked out. We had to bring in temporary water clarifiers, which run semi-trailers from /*New York*/," said Sellers.

Not only that, emergency managers now estimate 1,600 fires after a catastrophic quake.

Planners now look for mutual aid agreements with other states, not just other counties. And more stress than ever is on households to prepare for themselves.

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