Southern California Edison (SCE) is investigating whether a decommissioned electrical circuit may have been temporarily energized by high winds before the Eaton Fire ignited in Altadena. In a regulatory filing with the California Public Utilities Commission (CPUC), SCE acknowledged the possibility that the idle Mesa-Sylmar transmission line could have played a role in the fire. This revelation has raised concerns, as the company faces multiple lawsuits from fire victims.
Investigating the Role of the Mesa-Sylmar Transmission Line
The Mesa-Sylmar transmission line, which stretches through the Angeles National Forest, was decommissioned and is no longer in active use. However, new findings suggest that under certain conditions, such as strong winds, the line might have become momentarily energized through a process called electromagnetic induction.
How Could an Idle Power Line Become Electrified?
Electrical engineer Ken Buske, who has investigated over 1,000 fires, explained that a non-energized line can still conduct electricity if it is not properly grounded. If grounding connections weaken over time, induced current can cause sparks or arcing, which could potentially ignite a fire.
SCE acknowledged this possibility in its filing, stating that it is analyzing “the extent to which that line or its grounding could be related to the cause of the fire.”
Cellphone Video Provides Clues
A recently obtained cellphone video, recorded at 6:14 p.m. on January 7, provides new insight into the fire’s origin. The footage appears to show flames beneath the decommissioned tower rather than the active high-voltage transmission lines. Fire investigators have identified this area as the point where the Eaton Fire started.
Inspections and Findings
SCE stated that it had inspected the Mesa-Sylmar line annually between 2020 and 2024. Before and after the fire, photographs of the tower labeled “M16T1” did not show any clear signs of sparking or arcing. However, at the other end of the transmission line, another tower displayed potential arcing damage on grounding equipment for two of the three idle conductors.
The company is still investigating when this damage occurred and whether it could have played a role in the fire.
SCE’s Statement and Legal Challenges
SCE has maintained that no faults or anomalies were detected on its active high-voltage transmission lines in Eaton Canyon in the 12 hours leading up to the fire. Despite this, the company is facing dozens of lawsuits from fire victims who claim Edison is responsible for the blaze.
SCE has pledged to continue examining the equipment closely, including conducting laboratory testing on the decommissioned tower to determine if its grounding system failed.
The ongoing investigation into the Eaton Fire raises serious concerns about electrical safety, particularly regarding decommissioned power lines. If the idle Mesa-Sylmar transmission line was momentarily energized and sparked the fire, it could have significant implications for how old infrastructure is managed. As SCE continues its analysis, fire victims are seeking accountability through legal action. The final findings will be crucial in determining whether the utility company bears responsibility for the devastating fire.
