The state Public Utilities Commission said Wednesday it was investigating Southern California Edison to determine why thousands of the utility's customers were left without power for days after last week's windstorm.
Paul Clanon, the agency's executive director, said it would look into the cause of the outages, staffing levels and the length of time Edison has taken to respond to safety-related calls from its customers.
"We will determine whether SCE met all safety requirements and did all it could to prevent outages, and that it is now doing all it can to restore power and communicate with its customers," Clanon said. "If we determine that SCE has violated safety rules, it may face fines and penalties."
The utility issued a statement saying it would fully cooperate with the investigation.
"Some of our customers are upset, and we aren't happy either," SoCal Edison President Ron Litzinger said in the statement. "I'm committed to thoroughly examining what happened every step of the way and creating ways to improve our response in the future," Litzinger said.
The agency expects to issue a preliminary report in January.
About 1,000 Southern California Edison customers remained without service Wednesday, a week after the Nov. 30 storm that brought winds approaching 100 mph. That number was down from a high of more than 430,000 customers who experienced outages in the aftermath of the storm, nearly twice the number that Edison reported last week.
Edison's repeated promises to have power restored within 24 to 48 hours immediately after the storm angered and frustrated customers, tens of thousands of whom remained without electricity six days later. Edison on Wednesday estimated that power would be restored to the remaining 1,003 customers by Thursday afternoon.
Litzinger issued an apology to Edison customers earlier Wednesday.
"In some cases in the hardest-hit areas, we were not able to achieve our restoration targets or provide accurate information about their service. On behalf of the entire company. I apologize," Litzinger wrote in a letter posted on the company's website. "We understand that a number of our customers are frustrated, particularly those who have been without power for more than five days, and we thank them for their patience."
With workers still struggling to restore power, critics questioned whether local utilities are prepared for more serious disasters such as earthquakes.
"It tells me we have a long way to go in our emergency preparedness," said Democratic Rep. Adam Schiff, who represents one of the areas hardest hit by the recent windstorm.
Schiff said he wants to convene a panel to assess how the aftermath of the disaster was handled. And a day earlier, Los Angeles County supervisors sharply criticized Southern California Edison's response to the windstorm.
California Assemblyman Anthony Portantino, a Democrat from La Canada Flintridge, who asked Gov. Jerry Brown to declare a state of emergency, said he "wholeheartedly supports any investigation."
"If a windstorm can wreak this much havoc and have such a lasting impact, I want to be prepared for the next big disaster, and I think this windstorm showed us we're not prepared," he said.
The outages, caused mostly when downed trees hit power lines, were centered in the San Gabriel Valley northeast of Los Angeles. The tangled lines made it especially slow going for the estimated 276 restoration crews and 1,000 support crews that came from other parts of the state to help restore power.
Edison spokesman Steve Conroy said all the main power lines were repaired by midday Wednesday. Workers then went from home to home, repairing secondary lines that connect individual customers to power poles, he said.
Edison is doing "everything we can to get those lights on to those customers," he said.
On Tuesday, county Supervisor Michael D. Antonovich slammed Edison for its response to the windstorm.
He was particularly critical of Edison spokeswoman Veronica Gutierrez's explanation that the company was relying on media to get the word out about the status of repairs when hundreds of thousands of people were without electricity and had no access to radio, TV or the Internet.
"You really need direct contact with those neighbors. The media only works if you have electricity. They need to turn on the television. So that's stupid," Antonovich said.
People have become increasingly angry as the outrages wore on and overnight temperatures fell into the freezing range.
Frustration may have reached its limit for a 72-year-old man who police said was arrested Tuesday after he made death threats against Pasadena city workers over restoration of his power.
Geoffrey Commons was arrested on suspicion of making criminal threats and released after posting $50,000 bond, Pasadena police Lt. Pete Hettema said. Commons did not immediately return a call seeking comment Wednesday.
A preliminary estimate put damage and cleanup costs from last week's winds at $3.8 million in areas serviced by the county Department of Public Works. Department spokesman Bob Spencer said it could take weeks to clean up all the mess left by the winds.