Initial reports blame a utility worker doing maintenance near Yuma, Ariz., for triggering the massive blackout that affected residents across a large swath of southern California and Mexico.
The precise reason for the 12-hour, full system blackout affecting 5 million people across a large swath of Southern California and Mexico Thursday is still being investigated. By 2:15 a.m. Pacific time Friday, all but 200 megawatts of the initial 4,300 lost megawatts had been restored according the North American Regulatory Commission (NERC).
Initial reports blame a utility worker doing maintenance near Yuma, Ariz., for triggering the massive blackout that affected residents across San Diego County, southern Orange County, western Arizona, northern Baja California and parts of Mexico.
“NERC and [the Federal Energy Regulatory Commission] are partnering to conduct a full inquiry into the cause of this event,” said Gerry Cauley, president and chief executive officer of NERC, in a statement.
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Until investigations are complete, energy and utilities experts are raising serious questions about safety and oversight procedures, backup plans, and the overall health of the electrical grid in the region.