California fire safety officials have announced that they have warned Southern California Edison to improve weather tracking to help prevent wind-driven fire, but the utility maintained before the Eaton Fire that its effort met world standards.
State officials first told the utility back in 2022 that more frequent weather tracking was critical to boost Edison’s “situational awareness” in deciding whether to shut off power to prevent fires.
That warning may have been prescient, as in the hours before the Eaton fire, according to company officials, the weather tracking system did not detect severe enough winds to merit shutting off the transmission system where the fire started.
While the cause of the fire remains under investigation, authorities suspect that extreme Santa Ana winds drove a live power line close enough to energize a nearby, long-idled line. Surveillance video captured two flashes atop a tower at the end of Edison’s idled Mesa-Sylmar line, where other video shows the fire started at the base of the tower.
Ken Buske, a veteran Electrical Engineer and Fire Investigator shared: “In high winds, another power line could have gotten too close to this dead line.”
A sudden power surge into the dead line, he said, could lead to overheating and sparks at a faulty ground connection at a tower at the end of that idled line.
One fire expert says that Edison’s practice of checking wind conditions every ten minutes could have left it vulnerable to such a disaster.
Scott Stephens, a Fire Science Professor at UC Berkeley added: “The Santa Anas and the fire environment in Southern California — it’s one of the most difficult fire environments in the world.”
He says wind monitoring is becoming more important with research showing Santa Ana winds blowing stronger and later into the fire season.
In the hours leading up to the fire, Stephens said: “Those winds were very, very high.”
Stephens says in such extreme conditions, 10-minute weather monitoring may not have been enough to understand the threat.
“A lot of times you’re just going to miss the gusts – the gust’s going to be there and gone when they take another measurement.”
Three years before the fire, documents show, the State Office of Energy Infrastructure Safety began warning Edison about that 10-minute tracking rate. Officials told the utility that the 10-minute rate was “well below” the twice a minute frequency used by utilities to its north and south, which tracked winds twice a minute.
A PG&E Weather Expert said: “This center here, allows us to monitor weather at an unprecedented level. Discussing when its 30-second weather tracking system was rolled out back in 2021. San Diego Gas & Electric adopted a similar system at the time.
In their most recent assessment of Edison’s wildfire plan, state officials reiterated concerns that the 10-minute tracking frequency could limit its “situational awareness” to extreme conditions from climate change.
While pledging ongoing improvements to its weather monitoring system, Edison told state fire safety officials in October of last year that for now, it would continue using the 10-minute standard, which captured gusts lasting three seconds, in line with guidance from the World Meteorological Organization.
In a statement, Edison said that it sought to “mitigate” weather tracking issues flagged by authorities in 2022. It says the state was “satisfied” with its efforts when it ratified its most recent wildfire plan. While records show they signed off on Edison’s plan, state regulators listed the utility’s weather tracking level as needing “continued improvement.”
Southern California Edison has been warned by California fire safety officials to improve weather tracking to help prevent wind-driven fire.
One fire expert says that Edison’s practice of checking wind conditions every ten minutes could have left it vulnerable to such a disaster.
