Southern California Edison told the state Public Utilities Commission on Tuesday that one of its power lines might have started the Silverado Fire, an explosive blaze that critically injured two firefighters and caused tens of thousands of residents to flee their homes this week.

“It appears that a lashing wire that was attached to an underbuilt telecommunication line may have contact[ed] SCE’s overhead primary conductor, which may have resulted in the ignition of the fire,” SCE told the CPUC in an incident report. On a transmission tower or pole, an “underbuilt” line is one strung under electric power lines in a space reserved for telecommunication infrastructure.

“Preliminary information reflects SCE overhead electrical facilities are located in the origin area of the Silverado Fire,” the utility said. “We have no indication of any circuit activity prior to the report time of the fire, nor downed overhead primary conductors in the origin area.”

The 13,350-acre fire, which ignited and spread quickly during powerful Santa Ana winds on Monday, was 25% contained as of Wednesday afternoon, according to the California Department of Forestry and Fire Protection. It threatened thousands of structures northeast of the densely populated city of Irvine in Orange County.

Another blaze, the 14,334-acre Blue Ridge Fire, also started in the hills of Orange County on Monday. Firefighters brought it under control Wednesday as winds subsided and many residents in both fire areas were allowed to return to their homes.

2nd Incident

SCE’s report to the CPUC marks the second time this fire season that the state’s second largest utility has fallen under suspicion for starting a major wildfire.

In September, SCE filed a report with the CPUC saying the Bobcat Fire, burning in the mountains near Los Angeles, started in the same area and around the same time as the utility experienced a line fault. However, SCE said a fire camera had recorded smoke from the blaze shortly before its relay tripped, suggesting the fire preceded the line problem.

“The Bobcat Fire was reported in the vicinity of Cogswell Reservoir/Dam in the Angeles National Forest on Sunday, Sept. 6, 2020, at 12:21 p.m.,” SCE told the CPUC. “The Jarvis 12-kV circuit out of Dalton Substation experienced a relay operation at 12:16 p.m. on Sept. 6, 2020. The Mount Wilson East camera captured the initial stages of the fire, with the first observed smoke as early as approximately 12:10 p.m., prior to the relay operation.”

Both fires remain under investigation. The investigation of the Bobcat Fire is being conducted by the U.S. Forest Service, which on Sept. 15 “requested that SCE remove a specific section of SCE overhead conductor in the vicinity of Cogswell Dam,” the utility reported. (See Calif. IOUs Escape Blame for Fires So Far.)

SCE and Pacific Gas and Electric have been trying to avoid starting wildfires this season after three years of cataclysmic blazes in 2017-2019 that hammered the companies’ finances.

PG&E, which entered bankruptcy in January 2019 because of an estimated $30 billion in wildfire liabilities, has turned off power to hundreds of thousands of residents on multiple occasions this summer and fall in public safety power shutoffs (PSPS) meant to prevent utility equipment from sparking fires.

Nevertheless, a PG&E distribution line fell under scrutiny in the Zogg Fire, which killed four residents in a rural area near Redding, Calif. (See related story, PG&E Line Was Active when Zogg Fire Started.)

After emerging from bankruptcy in June, PG&E’s stock price, which exceeded $70/share before its equipment started the wine country fires of October 2017, has generally hovered around $9 to $10/share. It stood at $9.70/share at close of trading Wednesday.

SCE has been more conservative in its power shutoffs, partly because it lacks the PG&E’s vast territory in fire-prone areas and has had longer experience using PSPS.

As news spread of SCE’s possible involvement in the Silverado Fire spread, the already lagging stock price of its parent company Edison International fell further on Wednesday, from a high of $58.64/share at 10 a.m. ET to $56.56/share at the close of trading.