Professor Catherine Sandoval’s Blog
Santa Clara University School of Law
Associate Professor
Co-Director, Santa Clara University Law High Tech Law Institute
Former Commissioner, California Public Utilities Commission

Contact between PG&E’s uninsulated electric wires, trees, and other vegetation were the most common cause of the 2017 California wildfires, Northern District of California Federal Judge William Alsup tentatively found on January 17, 2019. Judge Alsup supervises PG&E’s five year probation after the company’s April 2016 felony conviction and January 2017 sentence for Pipeline Safety Act violations and obstruction of justice in connection with the 2010 San Bruno natural gas explosion and investigation. Judge Alsup proposes adding conditions to PG&E’s probation requiring electric infrastructure and record-keeping improvements to prevent fires.

Proper maintenance and operation of utility infrastructure is imperative to the safety and health of Californians, our communities, economy, and to mitigating climate change. My December 2018 article, Principles for Utility Regulation in the Face of Increased Wildfire Risk, published by Santa Clara University’s Markkulla Center for Applied Ethics, suggested that the CPUC should consider requiring insulated conductors (electric wires) and prohibit splices in areas of high wildfire risk. The CPUC has identified vegetation, conductors, splices and connectors between conductor segments, transformers, and utility pole failure as top causes of fires involving investor-owned electric facilities. The CPUC should submit this information to Judge Alsup, and initiate action to protect public safety. PG&E’s January 14 announcement that it intends to file for Federal bankruptcy by January 29 increases the imperative of ensuring that public safety is not compromised while PG&E seeks financing options.1

Judge Alsup’s January 17, 2019 Order tentatively finds that uninsulated wires, connected to utility poles in rural areas of California, played a major role in the 2017 fires:

“[T]he single most recurring cause of the large 2017 and 2018 wildfires attributable to PG&E’s equipment has been the susceptibility of PG&E’s distribution lines to trees or limbs falling onto them during high-wind events. This has most often occurred in rural areas where distribution lines use thirty-five to fifty-foot single poles and run through grass, brush, oak and pines. The power conductors are almost always uninsulated. When the conductors are pushed together by falling trees or limbs, electrical sparks drop into the vegetation below. During the wildfire season when the vegetation is dry, these electrical sparks pose an extreme danger of igniting a wildfire. By JANUARY 23, all parties shall comment on the accuracy of this tentative finding. The parties must also be prepared to discuss this tentative finding at the January 30 hearing.”2

Judge Alsup’s finding is consistent with the fourth principle my December 2018 article suggested: that the CPUC should consider requiring insulated conductors (electric wires) and prohibit splices in areas of high wildfire risk. My article suggested as a principle to reduce wildfire risk as climate change has increased swings between drought and extreme rain:

Fourth: Quickly learn from failures and near-misses. The CPUC and pole attachers should examine airline industry and hospital practices to learn from failures and adopt new rules as appropriate. We need to know not just that a utility pole failed in Lake County, causing a fire, but why it failed. The CPUC knows that vegetation management, conductors (electric wires), and spliced electric wires are top fire causes. The CPUC should consider prohibiting electric line splices and require insulated conductors in high-wildfire risk areas. The state of California must support the CPUC with necessary personnel, information technology, and databases to conduct and review safety inspections, enforce pole safety rules, and analyze safety incidents.3

PG&E’s probation and the CPUC’s actions to promote safety must take into account the CPUC’s studies of fires involving electric infrastructure. CPUC Safety and Enforcement Division (SED) Director Elizaveta Malashenko reported at the CPUC December 2018 Wildfire Safety En Banc, and in her blog that the “leading cause of fires ignited by utility infrastructure is a contact between electric equipment and an object, without equipment failure as a contributing factor.— She reported that “more than 50 percent of those incidents are due to vegetation (as opposed to vehicles, animals, balloons, etc.).”

The tables presented by Director Malashenko capture the role of vegetation and major components of electric infrastructure in causing fires:

CPUC Table 1, presented by Elizaveta Malashenko

Percentage of Reported Fires Suspected to be Caused by Object Contact - Listed by Object Type

Malashenko reported that “the second most common cause is “equipment/facilities failure”, with more than half of those incidents involving wire and splice failure.”

CPUC Table 2, presented by Elizaveta Malashenko

Percentage of Reported Fires Suspected to be Caused by Equipment Failure - Listed by Equipment Type

CPUC SED Director Malashenko highlighted this data as a good starting point for mitigation efforts. She added that weather conditions including humidity and wind are key factors in major wildfires and fire spread.

“Wildfires need three things to develop – fuel (vegetation), heat (ignition source), and air (weather),” Malashenko added. “Electric utility infrastructure can be a source of ignition, vegetation serves as the fuel and weather creates conditions for wildfires to spread,” she observed. Malashenko proposed considering “policy actions in three broad categories following the fire triangle model – fuel management, ignition control, and weather preparedness policies.”5

CPUC Table 3, presented by Elizaveta Malashenko

Chart with Fuel Management Policies, Ignition Control Policies, and Weather Preparedness Policies

Cal Fire’s reports6 on the 2017 wildfires that devastated many parts of California’s Wine Country found that vegetation including tree limbs coming into contact with PG&E power lines caused 14 of the 18 Wine Country fires in 20177. Cal Fire is still investigating the cause of the Tubbs fire that burned large portions of Napa and Sonoma counties in 2017. The cause of the 2018 Camp Fire in Butte County which killed 86 people and destroyed most of the town of Paradise, California, remains under Cal Fire investigation. In addition to vegetation contact with conductors, Cal Fire reported on several other causes of fires ignited on October 8 and 9, 2017.

Failure of a PG&E power pole caused wires and equipment to come in contact with the ground, igniting the Sulfur Fire in Lake County. For the Blue Fire in Humboldt County, Cal Fire found that a conductor (wire carrying electric power) disconnected from a connector, causing a power line to fall to the ground and ignite a fire On October 8, 2017. The Sonoma County “37 fire” was caused by an electrical issue associated with PG&E’s distribution lines, Cal Fire found. Cal Fire reported that the Phythian Fire, part of a complex of fires in Sonoma and Napa County that merged, was caused by a downed power line after PG&E attempted to reenergize the line. Cal Fire announced that the Cascade fire ignited after PG&E’s sagging electrical lines made contact in high winds, causing an arc which deposited burning or molten material on vegetation below.8

Neither Cal Fire nor the CPUC’s reports to date have explained why the utility pole failed in Lake County. Neither have they explained the cause of the electric distribution issue in the Sonoma County “37fire.” The CPUC should announce its process to examine the cause of these failures and take immediate steps to make sure they are not replicated.

Cal Fire’s report that a conductor (wire carrying electric power) disconnected from a connector, causing a power line to fall to the ground igniting the Blue Fire in Humboldt County, is consistent with CPUC SED Director Malashenko’s report that splices and connectors are the second leading cause of electric utility fires. Together with conductor failures, splices and connector problems accounted for 54.2% of the fires Malashenko studied for the CPUC.

The CPUC is undoubtedly investigating these issues as part of proceedings to determine whether PG&E violated CPUC rules and any penalty is merited. Such an Order Instituting Investigation (OII) is a lengthy proceeding, often taking a year to prepare for Commission consideration, and eighteen months or more to decide from the OII’s adoption. The CPUC in 2017 initiated an OII to determine whether to require a census of utility poles (CPUC I.17-06-027), a proceeding that aims to promote twin objectives of increasing safety and competitive access to utility poles.

The CPUC will also consider other proposals to reduce fire danger through the Wildfire Mitigation Plans due on February 6, 2019 as a result of SB 901 passed by the California legislature in 2018. Comments and reply comments on the plans are due in March 2019. SB 901 requires prompt CPUC action to initiate appropriate wildfire mitigation measures.

The CPUC needs to move quickly to take the lessons it has learned from analysis of previous fires, the utility pole proceedings, its fire hazard risk proceedings, and the mitigation plans and comments to order prompt steps to improve safety and forestall devastating fires. Judge Alsup has invited both the CPUC and Cal Fire to comment on his proposed ruling and attend the January 30 hearing to consider safety proposals. The PG&E federal probation and the CPUC’s regulatory process present important opportunities to improve the safety of the electric infrastructure which serves nearly 16 million Californians. Replacing uninsulated wires with insulated conductors, avoiding spliced wires in high-wildfire danger areas, and addressing the causes of transformer and utility pole failures are imperative to protect our state.

1 My January 17, 2019 blog argued that the federal government shutdown curtails PG&E’s options to use federal bankruptcy to raise funding and reorganize as bankruptcy filers will likely face delays in securing a hearing date and federal participation during the shutdown. My blog recommended that PG&E immediately file an advice letter with the CPUC to sell its headquarters building to raise cash, increasing creditor confidence, the loss of which led to the downgrade of its credit to junk status.




5 Id.


7 My previous blog stated that CalFire found PG&E caused 17 fires, but further review of CalFire reports confirmed that CalFire found PG&E’s infrastructure caused 18 fires including the October 8, 2017 Cherokee Fire.