WASHOUGAL — In the late spring heat, Bonneville Power Administration maintenance crews balanced on transmission towers in Washougal’s forested hills, waiting for a helicopter to hand off tools.
The team was tasked with replacing the tower’s insulators and various components, a routine job for BPA’s asset management that should not be overlooked, BPA District Manager Rob Robertson said.
“It’s critical in preventing wildfires,” he added.
Power lines are a wildfire risk if not properly tended. Live wire can ignite surrounding vegetation, a downed tree or branch can cause hot electrical arcs and failing equipment can shoot out sparks. BPA is one of the largest public utilities in the country, operating more than 15,000 circuit miles that cut through forest and high desert throughout Washington, Idaho, Montana and Oregon.
Wildfire seasons are becoming drier and hotter, a trend climatologists predict will continue as climate change intensifies. The National Interagency Fire Center’s latest summer forecast shows above-normal potential for wildfire conditions in Washington and Oregon, particularly in July and August.
BPA’s vast service area, coupled with hazardous weather trends, requires the agency to remain vigilant of potential faults in its system.
In case of a fire
BPA published its Wildfire Mitigation Plan in spring 2020, outlining protocols for preventive and responsive wildfire work. Actions are made months in advance of wildfire season and can be more intensive in high-risk areas, such as in Central and Eastern Washington.
“The plan, itself, is built on a simple, mathematical premise: Fire equals fuel plus ignition,” BPA spokesperson Kevin Wingert wrote in an email. “If we can mitigate the two legs of that equation, then we significantly reduce the chances of BPA equipment being associated with wildfire activity.”
Fuel is found in natural vegetation: pine needles, shrubs, fallen branches and trees. This material becomes more flammable as it dries in the summer heat. To prevent this, BPA removes tall trees and fast-growing, dense vegetation that could grow within 25 feet of the height of transmission lines.
Alongside routine maintenance checks and replacements, transmission infrastructure can automatically shut off if it detects smoke or if tree limbs have fallen onto lines. Bases of wood poles are coated with fire retardant in case of a low-level brush fire. Water trailers are strategically placed in vulnerable locations in case fire suppression is needed.
Workers often conduct ground and aerial patrols to monitor potential ignition, while on-staff weather forecasters compile daily reports tracking heat, wind and thunderstorms. BPA also maintains a live map of wildfires in its service areas that is available to the public on its website.
If all these approaches aren’t enough to compete with fire, there is an alternative that BPA can employ to prevent injury and damage as a last resort.
A last resort
In summer 2021, BPA incorporated a public safety power shutoff policy into its wildfire mitigation plan.
It’s a decision that carries weight, as some communities rely on a single source of power, Wingert said. Sometimes power outages can last for days and cost tens of thousands of dollars.
Deciding when to shut off power depends on a variety of factors: neighboring communities, the probability of a spark and system health. If wind blows faster than 60 mph and is coupled with a red flag warning from the National Weather Service, BPA will de-energize parts of its system, according to its mitigation plan.
In these cases, BPA should give at least 24 hours’ notice before conducting a public safety power shutoff.
Public safety power shutoffs are used by utilities in the Western Interconnection, one of the nation’s energy grids spanning 1.8 million miles through 14 states, Canadian provinces and a northern segment of Mexico.
Proponents of this tactic say it is necessary for public safety.
On Labor Day in 2020, a stretch of Whitman County in Eastern Washington blazed — eventually destroying 85 percent of buildings in Malden and Pine City, displacing many of their residents. The Seattle Times reported that this fire was one of at least 47 in early September that were ignited by power lines. Spokane-based Avista Utilities, the utility operating the lines responsible for the Malden fire, did not have a power shutdown plan.
The Whitman County conflagration, paired with fires in September 2020 throughout Washington and Oregon, led to the creation of BPA’s first wildfire mitigation plan.
