Is Colorado prepared for the next big wildfire? A look at the role of power companies

DENVER — Last month, the Palisades and Eaton Fires in California ravaged the city of Los Angeles, killing 29 people, destroying more than 16,000 structures, and creating what will likely be the costliest wildfire event in modern U.S. history.  

California has the most wildfires in the U.S., but when it comes to homes at risk from wildfires, Colorado ranks number two, according to the Insurance Information Institute and Core Logic, a property data and analytics company.

That’s because just under half of Colorado’s population, about 2.5 million people, live in what’s called the wildland-urban interface, an area of homes close to or within natural terrain and flammable vegetation. 

While the cause of the Eaton Fire is still under investigation and no conclusive findings have been made, sensor data and witness videos point to faults in the power lines run by Southern California Edison. The event has re-raised concerns over the role electric utilities play in igniting fires.

Only about 10 percent of wildfires are started by electrical utility equipment, but they were responsible for 8 of the 20 most destructive wildfires in California history.

 

The Boulder County Marshall Fire in December 2021, Colorado’s most destructive in terms of number of homes lost, ignited in part from a faulty ignition line. 

Investigators found that a sagging power line managed by Xcel Energy became disconnected amid fierce winds, sending sparks into the surrounding vegetation that were highly flammable following six months of drought. 

The fire ultimately consumed more than 1,000 homes and killed two people.

 

Over the past few years, electric utilities have ramped up wildfire mitigation efforts to prevent their equipment and infrastructure from becoming the source of an ignition.

 

“For over 100 years, the motto has been: reliability first, no matter what. Keep the lights on,” said Anne Sherwood, area vice president of wildfire mitigation policy at Xcel Energy. The company is the state’s largest electric utility providing gas and electric power to approximately 230 communities.

 

“Now because of the way things have evolved and the way that risk has increased, there are times when the conditions are to a certain threshold that public safety outweighs reliability. This new normal has been one of our biggest challenges,” Sherwood said.

 

To understand the role that electric utilities play in our growing wildfire-prone landscape, Rocky Mountain PBS spoke with Sherwood; Curtis Hartenstine, wildfire mitigation program manager at Tri-State Generation and Transmission (G&T); Kyri Baker, associate professor of engineering at UC Boulder; and Rebecca Samulski, executive director of Fire Adapted Colorado.

 

 

Sagging or downed lines from high winds can cause the energy in the line to hit surrounding vegetation and spark a wildfire. That’s what caused the deadly Lahaina fire in Maui in August 2023 that killed more than 100 people.

 

A tree or branch that falls or grows into a line can also cause a fire, which is why utility companies invest heavily in trimming trees and clearing nearby vegetation. As the power line’s electric current completes its circuit, it can heat up the tree. Officials determined the Dixie Fire in Northern California in 2018 started that way.

“The sparks are created because the power is flowing in places it shouldn't be flowing,” said Baker.

 

“It happens a lot. Most of the time it doesn't cause a fire. But that 1% of the time that it does, it's really, really bad,” she said.

Aged wires and transformers can also cause fires, as can worn-out insulation. “You might notice it’s hot in areas it shouldn’t be hot. The power’s flowing in an inefficient way and into places it shouldn’t be,” Baker said.

These issues can be mitigated with routine maintenance, repairs and upgrades. 

Hartenstine, who manages fire mitigation efforts at Tri-State G&T, said the task at hand is a challenge. The company, which generates and serves power to rural areas across four states including Colorado, has 36,000 structures across 200,000 square miles.

 

“With all these structures, all these distances, and the level of sensory equipment out there for our level of distribution, we're doing what we can, which I think is a great deal, but it doesn't allow us the precision that we'd always like.”

One of the most critical new technologies some utility companies are deploying to prevent a catastrophic wildfire is called enhanced powerline safety settings or EPSS, which Pacific Gas & Electric (PG&E) piloted in 2021 in California.

 

If something comes into contact with a power line, the system automatically turns off power and de-energizes within one-tenth of a second. When this happens, electricity doesn’t return to consumers until the utility company is done investigating the fault.

 

Xcel Energy began deploying EPSS in March of 2024 after a California utility advised them to prioritize the technology, said Sherwood.

 

The company says it places powerlines into the EPSS sensitive setting whenever certain weather conditions are forecast.

 

Xcel Energy has also invested in drones to identify defects in its equipment; artificial intellgience cameras to detect wildfires; underground utility lines in certain high-risk areas; and regular vegetation management to ensure brush is cleared away from their structures.

 

These technologies are costly and require significant resources and manpower, so the company prioritizes the most at-risk communities first.

 

Hartenstine said Tristate G&T utilizes immense amounts of data to assess risk and prioritize where to perform repairs and maintenance.

“We’re as data driven as we can be,” he said. “If we have the data, then we can act on it.”