Nearly 1.5 million San Diego Gas & Electric (SDGE) customers are reported without power after a major problem occurred with the transmission line from Arizona into California at 3:57 pm Thursday.
San Diego County Supervisor Dianne Jacob said the county qhas activated its Emergency Operations Center.
Power is out throughout the county, as far east as Phoenix, as far north as Orange County, and Coachella Valley and into Mexico.
The region will be without power overnight and into tomorrow, SDGE said.
"We have no idea when power will be restored," said Jacob. "This sure makes a good argument for in-basin generation so we don't have to rely on a large transmission line"
Jacob advises people to shut off their air conditioners. Do not turn them on until the lights come on, says SDGE.
The FBI said the outage is not related to a terrorist threat.
Update - 8:00pm. Dennis Cushman of the San Diego County Water Authority says "Ramona is one of four districts that need to conserve water.". No outside watering. Essential use only. Tune into 600 AM radio for the latest updates.