PG&E Reports Describe Falling Trees, Downed Power Lines on Night Deadly Fires Started

Updated 6:45 p.m. Tuesday

Pacific Gas and Electric has informed state regulators of at least eight instances in which trees or tree limbs brought down power lines in the hours when a series of devastating wildfires started in the North Bay earlier this month.

PG&E’s incident reports to the California Public Utilities Commission provide brief accounts of trees toppling in high winds in an area stretching from Potter Valley, in Mendocino County, to the outskirts of Napa late the night of Oct. 8 and early Oct. 9.

The exact location of the incidents is redacted from the documents, released Tuesday by the CPUC. But many of the incidents were located inside or near the perimeters of the wildfires. In most of the reports, PG&E said Cal Fire had taken possession of tree limbs and damaged electrical equipment as part of its investigation into how the wildfires started.

“This is definitely something the investigators will take a look at,” Cal Fire spokeswoman Lynne Tolmachoff said Tuesday. She said the agency will try to determine whether there’s a link between the fires — which Cal Fire is calling the October 2017 Fire Siege — and PG&E’s incident reports.

Cal Fire has yet to announce a cause for the fires across Northern California that killed 43 people, destroyed an estimated 8,900 structures, burned more than 245,000 acres and forced more than 100,000 residents from their homes.

“There’s a lot of leg work to do, there’s a lot of interviews to do, a lot of people to talk to … and a lot of things to rule out,” Tolmachoff said of the investigations.

The CPUC requires utilities to cooperate with investigations with any major incidents. If Cal Fire determines that PG&E power lines or equipment caused the fires, then the CPUC will open a formal investigation. Utilities are required to preserve evidence for up to five years.

According to the brief accounts PG&E submitted to the CPUC, trees took down or damaged power lines near Napa and Calistoga in Napa County; near Santa Rosa, Glen Ellen, Kenwood and Geyserville in Sonoma County; and Potter Valley in Mendocino County. Similar damage was reported at locations in Lake, Butte and Yuba counties, where fires also broke out.

In several instances, the PG&E reports note high wind speeds at the time a tree fell. For instance, the utility said, wind gusts reached 65 mph in the Geyserville incident, 58 mph in the Glen Ellen case and 50 mph in Potter Valley.

In addition to the tree-related equipment damage, the PG&E reports include several cases in which the utility says Cal Fire took possession of apparently undamaged power lines and other equipment as part of its probe into the fires.

Under CPUC rules, utilities are required to file safety incident reports like those the commission released Tuesday.

“They’re part of what we’re examining in our investigation,” said CPUC spokeswoman Constance Gordon. She said that the redactions — which include details of the location and type of power facilities involved in the Oct. 8-9 incidents — are temporary “pending completion by our staff and Cal Fire of the initial investigation review and the collection of evidence. Once there’s no longer a serious risk that the integrity of the evidence and data collection process will be compromised, the original versions of the incident reports will be posted in place of the redacted versions.”

In a statement later Tuesday, PG&E said it is “committed to being open and transparent throughout this process. … The information provided in these reports is preliminary and PG&E is fully cooperating with the investigations of Cal Fire and the CPUC. There has been no determination on the causes of the fires.”

You can read PG&E’s incident reports to the CPUC here: [doxPGECPUC]

This story was updated to include a PG&E statement on its incident reports.