California's Department of Forestry and Fire Protection has determined that 12 wildfires that burned in Northern California last year were caused by electric power and distribution lines, conductors and power poles.
Several of the fires investigated make the list of the top 20 most destructive wildfires in state history.
The findings are a blow for California’s investor-owned utilities, which could owe billions of dollars in damages if their equipment is found to have caused the devastating fires that swept through the state last year.
Utilities are pushing state lawmakers for changes to laws that hold them liable for any damage their equipment creates without letting them automatically pass on the cost to ratepayers.
The state report released Friday found that the Redwood Fire, which torched more than 36,000 acres, destroyed 543 structures and killed nine people in Mendocino County, was caused by trees or parts of trees falling onto Pacific Gas & Electric power lines.
The Nuns Fire and four other fires in Sonoma and Napa counties that merged to burn over 56,000 acres, destroy over 1,000 structures and kill three people were caused by trees falling onto Pacific Gas & Electric power lines and by a downed power line.
And the Atlas Fire, which burned more than 51,000 acres, destroyed over 780 structures and killed six people in Napa County began when trees touched Pacific Gas & Electric power lines, the report said. Five other, less destructive wildfires were also found to be caused by utility equipment.
State investigators found evidence of possible violations of state law in their assessment of eight of the twelve fires, including the Atlas Fire and four of the fires that merged with the Nuns Fire.
"We look forward to the opportunity to carefully review the CAL FIRE reports to understand the agency's perspectives," Pacific Gas & Electric said in a statement published online. "Based on the information we have so far, we continue to believe our overall programs met our state's high standards."