Updated at the bottom: The California Independent System Operator will join the party, er we mean, investigations. First posted at 7:09 a.m.

When the power went out yesterday for a large swath of Southern California only days before the anniversary of 9/11, our thoughts naturally took us to a possible act of terrorism.

After all, the San Onofre nuclear power plant seemed to go off line about the same time people from Ensenada to South Orange County saw their lights go out. Was there an attack on SoCal's main radiation station? But Al-Qaeda ain't got nothing on human error.

No, the punchline to a night without a/c during one of the hottest weeks of the year:

It only took one employee to set the whole thing off.

APS, the Arizona company that owns the 500 kV transmission line near Yuma that feeds San Diego and environs said in a statement:

The outage appears to be related to a procedure an APS employee was carrying out in the North Gila substation … Operating and protection protocols typically would have isolated the resulting outage to the Yuma area. The reason that did not occur in this case will be the focal point of the investigation into the event, which already is under way.

Hope so.

We can just see the guy, plump like Homer Simpson, wearing a hardhat, and flipping the wrong switch. Do'h. As many as 5 million people were effected.

Here's the thing. Dude (and you know women don't make mistakes like this) probably made an honest uh-oh. But how in the hell is it possible for one person to take one of America's largest metropolitan areas — a major city, parts of a different country, parts of a different state, too — off-line in almost an instant?

If a hapless American worker can do this, just imagine what a terror-minded MacGruber could do with some chewing gum and a paper clip.

Should we — oh, maybe — design a fail-safe here?

And, for criminy, why, as SDG&E officials explained, are there only two lines feeding all of San Diego and its neighbors, from South O.C. to Ensenada? Snip-snip and you're a caveman again. Really?

The outage knocked out SoCal's only nuclear power plant and could have put air traffic in jeopardy, as the FAA's airspace controllers for L.A. and Southern California are based in San Diego.

Let's not just point fingers here. Let's fix this. We have some electrical tape we can donate to the effort.

Update: Look out, Homer, because the feds are getting involved in this.

Today the Federal Energy Regulatory Commission (FERC) said it's joining hands with the North American Electric Reliability Corporation (NERC) for a joint inquiry into the Great SoCal Blackout of 2011.

Gerry Cauley, president and chief executive officer of NERC:

NERC and FERC are partnering to conduct a full inquiry into the cause of this event. Partnering brings together the expertise of both organizations, and emphasizes the importance placed on reliability of the bulk power system.

Somebody's going to get FERC'd.

Update No. 2: The California Independent System Operator stated this afternoon it would launch its own joint task force ” … in close coordination with the Western Electricity Coordinating Council (WECC)” to look into the blackout. According to a Cal ISO statement:

The task force will conduct a full investigation in a thoughtful, collaborative and transparent fashion to guard against it happening again.

Cal ISO CEO Steve Berberich:

We now turn our focus to root-cause analysis to investigate the reason for the series of events that triggered the widespread power outage.

[@dennisjromero/djromero@laweekly.com]

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