If the Big One hits, we're f—'d. You're saying, Yeah-yeah, tell me something I don't know.

But here's the thing: Experts say our only hope of getting power back 72 hours after a huge earthquake in Southern California is the San Onofre Nuclear Generating Station. As you might have heard, the San Onofre Nuclear Generating Station has been down for months.

No-nukes activists like this, of course. But consider what we'd face if the San Andreas Fault were to explode today:

Weeks if not months without power. No iPhones. No computers. No refrigeration. No stoplights. No lights, period — for days and days — in the middle of a natural disaster. Lucy Jones, seismologist with the U.S. Geological Survey and a foremost expert on the Big One, told the Weekly:

To restart the grid, to come up from a black start, you need a large source of power. San Onofre would be needed to start back up.

San Onofre officials have found alarming wear on steam-generator tubes. This has prompted them to shut down the whole plant until they can figure out how to prevent this from happening again.

Both of the plant's working units were taken offline in January.

This week California ISO is warning the public that hotter-than-normal temps in July and August paired with the temporary loss of San Onofre could mean rolling blackouts as the grid operator figures out how get us the juice we need.

It is asking consumers to cut back on electricity use as a precaution.

Now, the Big One might not happen in our lifetime, but it's going to happen, experts say. The working scenario is a 7.8 quake erupting on the San Andreas in the Mojave Desert.

Jones told us that such a quake could produce a 20-foot crack or offset near Palm Springs, and that would rip the main trunk lines providing Southern California with juice from the Colorado River.

Not only that, but this scenario predicts that much of the entire Western United States would be without power as key parts of the West Coast grid would subsequently fall like dominoes.

With San Onofre working, however, it would take 72 hours to do safety checks and get its reactors back online, Jones said. But that would be with San Onofre working.

Without San Onofre, we'd be in the dark for a long time. Jones:

It would take weeks to restart the grid.

So as you prepare for that 4th of July barbecue next week, consider saving some of that mesquite, charcoal and beer for a proverbial rainy day.

[Added at 2:18 p.m.]: An official with Southern California Edison, which runs San Onofre, got back to us today and sent us this fact sheet about the plant's ability to withstand earthquakes and tsunamis. Check it out:

SONGS13 Design and Emergency Response Capability

[@dennisjromero / djromero@laweekly.com / @LAWeeklyNews]

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