The attack began just before 1 a.m. on April 16 last year, when someone slipped into an underground vault not far from a busy freeway and cut telephone cables.
Within half an hour, snipers opened fire on a nearby electrical substation. Shooting for 19 minutes, they surgically knocked out 17 giant transformers that funnel power to Silicon Valley. A minute before a police car arrived, the shooters disappeared into the night.
To avoid a blackout, electric-grid officials rerouted power around the site and asked power plants in Silicon Valley to produce more electricity. But it took utility workers 27 days to make repairs and bring the substation back to life.
Nobody has been arrested or charged in the attack at PG&E Corp.'s Metcalf transmission substation. It is an incident of which few Americans are aware. But one former federal regulator is calling it a terrorist act that, if it were widely replicated across the country, could take down the U.S. electric grid and black out much of the country.
The attack was "the most significant incident of domestic terrorism involving the grid that has ever occurred" in the U.S., said Jon Wellinghoff, who was chairman of the Federal Energy Regulatory Commission at the time.
The Wall Street Journal assembled a chronology of the Metcalf attack from filings PG&E made to state and federal regulators; from other documents including a video released by the Santa Clara County Sheriff's Department; and from interviews, including with Mr. Wellinghoff.
Comment: Isn't it a little weird we're only hearing about this now, almost a full year after the fact? Also worth noting - that this happened one day after the Boston Marathon bombings.
There's also one other strange power-station-incident from last year: Arkansas man charged in connection with power grid sabotage