Safeguards Failed in Massive Power Outage in Western U.S., Mexico
Routine work on a substation apparently led to a power outage that left more than 1.4 million customers – about 5 million people – without power for 12 hours Sept. 8 and 9 in Southern California, Arizona and Mexico.
According to the Arizona Public Service, the outage began about 3:30 p.m. PDT Thursday when a major 500-kV line from Arizona to Southern California tripped off. The outage forced the automatic shut down of the San Onofre Generating Station, a nuclear powerplant. The powerplant and power imported from Arizona on the 500-kV line are the region’s primary sources of power. Without that electricity, San Diego Gas and Electric, and other utilities in the region, did not have enough power to keep the lights on.