(TNS) — LOS ANGELES — In a sweeping effort to reduce the wildfire risk from electric power lines, Southern California Edison said Monday it wants to spend $582 million for a series of improvements to its grid that likely would mean higher bills for ratepayers.

Edison’s action comes while another huge California utility, Pacific Gas & Electric, faces up to $15 billion in losses from last year’s wine country fires, which destroyed more than 8,000 homes and killed more than 40 people. Residents have blamed downed power lines for the fires, though officials have not completed their investigation of the causes.

Many of California’s most destructive fires have been fueled by powerful winds, which in some cases have caused power lines to snap off and spark blazes. Utility companies are already on the hook for hundreds of millions of dollar in losses, but officials have warned that the losses will grow much steeper if the agencies can’t find ways to reduce the risks.

Edison is asking the state for permission to spend the $582 million on improvements, including strengthening poles and using better technology to determine when winds put the power grid at risk.

Over the next two years, an estimated 600 miles of exposed power lines would be replaced with insulated ones immune to sparking if they came in contact with a fallen branch or a Mylar balloon.

Officials said ratepayers would see their bills increase between 81 cents and $1.20 a month, but far less than if Edison becomes liable for a catastrophic fire like the one that hit Sonoma, Napa, Lake and Mendocino counties last October. Edison is estimated to face up to $4 billion in losses from the Thomas fire, which hit Ventura and Santa Barbara counties in December, and the Montecito mudslide that occurred a month later.

PG&E’s potential losses there were so vast that the utility said it faced possible bankruptcy if it did not get some relief from the state. Those concerns prompted the state Legislature last month to approve a bill that would allow PG&E to borrow money for its 2017 wildfire costs while using funds collected from ratepayers to pay back the loan. PG&E lobbied lawmakers heavily for help, warning that Wall Street investors could downgrade the company’s credit rating without relief from the Legislature. The bill was controversial, with some calling it a bailout for a utility that should have been better prepared to deal with the wildfire danger.

Wildfire liability has been a growing problem for California’s utilities. San Diego Gas & Electric has spent more than a decade seeking permission to pass along to ratepayers $379 million in costs from the deadly 2007 fires in San Diego County, which destroyed hundreds of homes. SDG&E spent $2.4 billion to resolve more than 2,000 lawsuits related to those fires, but the utility insists the blazes were ignited by factors beyond its control — including extreme Santa Ana winds and a tree limb that fell onto an SDG&E line due to high winds.

The upgrades Edison is proposing would reduce those risks, said Bill Chiu, the director of Edison’s Grid Resiliency and Wildfire Safety program.

“In the state of the ‘new normal,’ there’s this tremendous urgency to act quickly. Eight of the 20 most destructive fires in California happened since 2015,” Chiu said. “Even though wildfires start for many reasons, utility power lines is almost 10 percent. We feel it’s necessary we do our part.”

©2018 Los Angeles Times Distributed by Tribune Content Agency, LLC.