Power Outages Roll Through Southland

A disruption along a major transmission line and higher than predicted temperatures prompted utility officials to order rolling blackouts throughout Southern California on Thursday, leaving between 250,000 and 500,000 homes and businesses without electricity for 30 minutes or more, utility officials said.

The California Independent System Operator, the not-for-profit entity that oversees the state’s power grid, declared a Stage 3 transmission emergency just before 4 p.m., after a long-distance transmission line connecting southern Oregon and Southern California “tripped off line,” power authorities said.

The blackout affected a wide swath of the Southland, including Ventura, Thousand Oaks, Camarillo, Long Beach, Torrance, Huntington Beach, Irvine, San Bernardino, Ontario, Fontana, La Puente, Cathedral City, Chino Hills and Palm Desert, said Southern California Edison. Though it was initially planned to last until 7 p.m., the emergency was canceled at 4:35 p.m.

Despite lasting only a brief period, the event was one of the largest electrical shortages to hit the region since the power crisis of 2000-01 and prompted Gov. Arnold Schwarzenegger to make an emergency stop at Cal-ISO’s headquarters in Folsom for a briefing. Eager to stem fears of a renewed energy shortage, officials stressed that Thursday’s outage involved power transmission and not supply.

“The key thing is, going forward, we should have enough power,” said Jim Detmers, an operations executive at the ISO. “We don’t expect this to reoccur.”

What prompted the outage was a disruption along the 500,000-volt Pacific DC Interline at a time of heavy power consumption. The disruption caused the sudden loss of 2,800 megawatts, the ISO said. A megawatt is enough energy to power 650 homes.

“The loss of that resource, coupled with temperatures that were 10 to 14 degrees above forecast, required us to take immediate action to reduce demand on the system,” said ISO spokesman Gregg Fishman. Though utility officials will usually warn customers of upcoming blackouts and call for power conservation or voluntary cuts, there was not enough time to do so Thursday.

The downed transmission line is operated by the Los Angeles Department of Water and Power. Both the DWP and the ISO said it was unclear what caused the disruption.

“We really don’t know yet,” Fishman said. “Events that can cause something like this include a tree branch falling onto the line or a lightning strike.”

The blackouts had little apparent effect on residents, as most customers were businesses, a Southern California Edison spokesman said. Officials in affected cities said there appeared to be little outcry about the outage.

“We took a few calls regarding intersections being out, but nothing special,” said Lt. Hans Strand, a spokesman for the Orange County Sheriff’s Department. One intersection in Huntington Beach was the scene of a minor collision, but it was unclear whether the collision was related to the power outage, said Lt. John Cottriel of the Huntington Beach Police Department.

Rozanne Adanto, community services director in La Puente, said the city received an e-mail notifying it of possible power outages at 4:10 p.m. “I did notify staff to keep saving their documents on the computer,” she said. “Maybe we’ll all get to go home early.”

Often referred to as “rolling blackouts,” the controlled outages generally last up to one hour in an area before they are moved to another. Utilities scatter the outages to lessen their impact.

Schwarzenegger compared Thursday’s crisis with an automotive problem.

“I think it’s the same as when you have a car,” he said. “You can have the best car in the world, but a car can break down. The key thing is you have an organization that responds quickly.”

In an odd coincidence, Thursday also was the day that legislators rejected a plan by the governor to regulate state energy agencies. Schwarzenegger, who said he inherited an “outdated” system, will meet with lawmakers today to discuss the matter.

At least one Democratic legislator, however, was quick to criticize the Republican governor for the lights going out Thursday.

Lloyd Levine, chairman of the Assembly Utilities and Commerce Committee, said Schwarzenegger had broken a promise he made in December that Californians would have affordable and reliable energy.

“Since taking office, the governor is spending time trying to rearrange the deck chairs of California’s energy agencies and trying to push us back to the failed model of deregulation,” Levine said in a press release.

Thursday’s outage, however, was a far cry from the crisis that gripped California in 2000 and 2001, when high demand, high wholesale energy costs, transmission glitches and a tight supply caused rolling blackouts throughout the state. California officials also accused several major power producers of manipulating the electricity market through false plant shutdowns and trading schemes.

Times staff writers David Haldane, Robert Salladay and Catherine Saillant and the Associated Press contributed to this report.