The cause of San Diego blackout could be related to a procedure their employee was carrying out, according to the latest update from Arizona Public Service (APS).
Traffic condition during San Diego blackoutImage Credit: Getty Images
As announced by APS via their official website on Thursday, September 8, 2011, the massive power outage in San Diego started in a Hassayampa 500 kV transmission line near Yuma, Arizona.
“the outage appears to be related to a procedure an APS employee was carrying out in the North Gila substation, which is located northeast of Yuma.” APS said on its press release.
“Operating and protection protocols typically would have isolated the resulting outage to the Yuma area.” APS added, noting that a thorough investigation is under way on why the isolation did not occur.
“We are working hard to restore our customers as quickly and safely as possible,” APS President and Chief Operating Officer Don Robinson said in the report.
As reported earlier, the San Diego blackout started at around 4 p.m. PST on Thursday, and San Diego Gas and Electric (SDGE) have already restored power to 18,000 customers in Orange County.
SDGE then said that around 1.4 million customers could be affected and could extend through the night and until Friday.