Sacramento, Oct. 9 2018 – After a thorough investigation, CAL FIRE has determined the Cascade Fire which occurred during the October 2017 Fire Siege was started by sagging power lines coming into contact during heavy winds.
No violations of the Public Resources Code were found by CAL FIRE.
The Cascade Fire in Yuba County, started on the evening of October 8 and burned a total of 9,989 acres, destroying 264 structures and resulted in four civilian fatalities and one firefighter injury.
A high wind event in conjunction with the power line sag on two conductors caused the lines to come into contact, which created an electrical arc. The electrical arc deposited hot burning or molten material onto the ground in a receptive fuel bed causing the fire. The common term for this situation is called “line slap” and the power line in question was owned by the Pacific Gas and Electric Company.
The investigative report has been forwarded to the Yuba County District Attorney.
In total, the October 2017 Fire Siege involved more than 170 fires and burned at least 245,000 acres in Northern California. Approximately 11,000 firefighters from 17 states and Australia helped battle the blazes.
CAL FIRE investigators were dispatched to the fires last year and immediately began working to determine their origin and cause. CAL FIRE investigators continue to investigate the Tubbs Fire and will release the report once it is completed.
Californians are encouraged to remain vigilant and prepared for wildfire. For more information on how to be prepared, visit or