The state’s Public Utilities Commission has launched an investigation into whether PG&E’s maintenance of its power infrastructure in Sonoma and Napa counties may have played a role in the deadly Wine Country fires.

The regulatory agency sent a letter to the utility ordering that it preserve all equipment possibly related to the string of fires, as well as internal communications discussing the disaster. The PUC president announced that his agency would focus on the energy company’s maintenance history.

“We are in contact with PG&E about their response, and we’ll be collecting information about maintenance history and vegetation management in these areas,” President Michael Picker said at the agency’s recent meeting (3 minute mark).

Related Articles Marin fire officials advocate more preemptive burns

Marines from Camp Pendleton quickly train to help with Creek Fire nearing Mammoth Lakes

Bobcat Fire grows to 91,000 acres as buildings burn

3 people arrested in Oregon accused of setting up illegal roadblocks near wildfire evacuation zones

California wildfires: Firefighter killed battling blaze sparked by gender-reveal party On Thursday, Elizaveta Malashenko, director of the PUC’s safety and enforcement division, sent a letter to PG&E ordering it to “preserve all evidence” regarding the string of devastating fires that have killed dozens of people and destroyed thousands of homes. A Bay Area News Group review of fire dispatch calls from the first 90 minutes of the firestorm indicate a number of downed wires and blown transformers simultaneous to multiple fires igniting. No official cause of the fires has been determined.

“All failed poles, conductors and associated equipment from each fire event” must be preserved, cataloged and tagged so that the PUC can properly review the evidence, Malashenko ordered in the letter.

The commission’s safety division went further.

“PG&E must inform all employees and contractors that they must preserve all electronic (including emails) and non-electronic documents related to potential causes of the fires, vegetation, maintenance and/or tree-trimming,” Malashenko stated in the letter.

Telecommunications companies also were ordered by the PUC to preserve an array of evidence.

“AT&T, AT&T Wireless, Frontier, Comcast Phone, Verizon Wireless, T-Mobile and Sprint have an obligation to preserve all evidence with respect to the Northern California wildfires,” Malashenko wrote in a letter to telecommunications firms Friday.

San Francisco-based PG&E said it has received the PUC’s letter.

“Since the wildfire began Sunday night, in the cases where we have found instances of wires down, broken poles and impacted infrastructure, we have reported those to the commission and continued to share that information with CalFire,” PG&E spokesman Donald Cutler said.

President Picker said PUC investigators have been working with Cal Fire inspectors to share findings as part of a Memorandum of Understanding signed in August.

“Cal Fire provides findings and immediate facts to us,” Picker said. “(PUC) follows after an event to conduct investigations if utility involvement is evidenced.”

That work has been slowed, however, by the ongoing firefight, he said, as the PUC and PG&E crews have been limited in accessing key areas.

Meanwhile,state Sen. Jerry Hill, D-Redwood City, a frequent PG&E and PUC critic, said he plans to hold a hearing on the fire and particularly explore whether there was any shirking of vegetation-maintenance requirements, as has been the case with the utility in the past.

“I’m hoping that’s not the case here,” Hill said by phone Saturday while vacationing in Europe. “If it is, that should signal the end of PG&E.”

Hill chairs a Senate Subcommittee on Gas, Electric and Transportation Safety, and has held previous hearings on power lines and wildfire safety and prevention.

Staff writer George Avalos contributed to this report.