Cause of Largest Northern CA Blaze Undetermined

June 09 -- When state fire officials on Friday released the causes of a dozen wildfires that ravaged Northern California last fall, they didn’t include the most destructive blaze in state history: the Tubbs Fire.

The cause of that inferno, which swept west from Calistoga to Santa Rosa and leveled whole neighborhoods, has been the most anticipated from the October siege, due to its immense damage. The fire killed 24 people and ruined more than 5,600 homes, businesses and other structures.

Cal Fire investigators determined that 12 other blazes were sparked by Pacific Gas & Electric Co.’s power lines or electrical equipment, a finding that many had anticipated due to early reports of problems with the lines amid a fierce windstorm. But the precise trigger for the Tubbs Fire has been more of a mystery.

In the days after the fire sparked on the night of Oct. 8, Cal Fire investigators were focused on a small property off Highway 128 on North Bennett Lane near Calistoga. At least one home was destroyed on the property.

PG&E has said the fire may have started with privately owned electrical equipment on the property. One month after the fire began, the utility wrote in a court filing that “preliminary investigations suggest that this fire might have been caused by electrical equipment that was owned, installed and maintained by a third party.”

The owner of the home told The Chronicle that it was unoccupied when the fire started. Reached by phone at her Riverside County home this week, Ann Zink, 90, said she didn’t know how the fire started but had heard that “a tree fell on some wires and the wires came down.”

PG&E could face billions of dollars in potential liability if its equipment is blamed for the Tubbs Fire.

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