Cal Fire points to PG&E equipment as cause of Sonoma Valley fires
“Based on my origin and cause investigation, I determined the Nuns Fire ignited as a result of a section of an alder tree detaching from the stem and contacting an energized power line conductor causing the conductor to fall to the ground contacting a receptive fuel bed and ignited the Nuns fire.”
Those are the technical, clinical words of a Cal Fire investigator as to the cause of the fire that started the evening of Oct. 8 in a field at the intersection of Nuns Canyon and Nelligan roads. Fueled by high winds combined with low humidity, that particular firestorm caused catastrophic damage to Glen Ellen and the Trinity/Cavedale roads area, burning 231 homes in total.
Cal Fire’s report on the Nuns Fire was part of an announcement on June 8 stating that 12 of the Northern California wildfires last October were caused by electric power and distribution lines, conductors and the failure of power poles.
A number of other fires, including the major fire of October, the Tubbs Fire, which started in Calistoga and tore into Santa Rosa destroying 3,000 homes, are still under investigation by Cal Fire as to the cause.
The Nuns Fire investigation report was publicly released because it was determined that, even though PG&E operated the power equipment involved, there was no evidence that state regulations – having to do with the clearing of brush around power lines and the proper maintenance of power equipment – were violated.
Investigations into three other fires of the 12 in Cal Fire’s June 8 announcement also found no sign of state rules violations:
• The Redwood Fire in Mendocino County, caused by trees or parts of trees falling onto PG&E power lines. 36,523 acres and 543 structures lost.
• The Cherokee Fire, in Butte County, caused by tree limbs coming in contact with power lines. 8,417 acres and six structures destroyed.
• The 37 Fire, a vegetation fire in the area of Lakeville Highway and Highway 37, caused by an electrical source associated with PG&E distribution lines. 1,600 acres and six structures.
The eight other fires referred to in Cal Fire’s June 8 announcement did show evidence of alleged rule violations by the utility, so the investigations were forwarded to the appropriate county District Attorney’s office for further review. They include:
• The Adobe Fire, started on the west side of the Chateau St. Jean tasting room in Kenwood near Goff Road, caused by a eucalyptus tree falling into a PG&E power line. The fire destroyed homes in the Adobe Canyon Road area, the Treehaven area, and Lawndale/Bristol/Schultz roads area, eventually moving to the Bennett Ridge neighborhood. Over 200 homes destroyed.
• The Norrbom Fire, started near the end of Norrbom Road in Sonoma, caused by a tree falling into power lines.
• The Partrick Fire, started in Napa County, caused by an oak tree falling into power lines.
• The Pythian Fire, which began later on Oct. 14, caused by a downed power line after PG&E attempted to re-energize the line.
• The Atlas Fire, in Napa County, 51,624 acres and 783 structures, and six people killed. Limbs and a tree came down on a power line.
The Norrbom, Adobe, Partrick, Pythian and Nuns fires all merged into what is commonly referred to now as just the Nuns Fire. In total, these particular fires burned 56,556 acres, and destroyed 1,355 structures, with three civilian fatalities.
In response to Cal Fire’s recent actions, PG&E released a press release, stating in part, “We look forward to the opportunity to carefully review the Cal Fire reports to understand the agency’s perspectives. Based on the information we have so far, we continue to believe our overall programs met our state’s high standards.”
The press release listed a number of wildfire safety programs they have in place, and in the face of increasing extreme weather events, emphasized the need for utilities, the state, and first responders, to work together to prevent wildfires and enhance the state’s infrastructure.
PG&E touted its Vegetation Management Program, where they said they inspect and monitor every PG&E overhead electric transmission and distribution line each year, with some locations patrolled multiple times. The utility also stated it prunes or removes approximately 1.4 million trees annually.
The Northern California wildfires of last October have exposed PG&E to potentially billions of dollars in damages, with multiple of lawsuits already filed by over 1,000 fire victims, and attorneys signing up more and more clients. Sonoma County has also sued PG&E, in part seeking to recover millions of dollars in damage to county infrastructure.
While it is not surprising that a number of Cal Fire investigations so far have pointed the finger at PG&E equipment as the source of many blazes, Cal Fire’s official findings are sure to help bolster cases charging that the utility is ultimately responsible and should be held accountable.