Gusty winds pushed a wildfire in western Montana into Bonneville Power Administration transmission lines late Wednesday, shutting down a major line to the West Coast and forcing officials to pull firefighters off the lines, officials said.
There were no power outages and none expected because the BPA said it could reroute the flow of electricity without major difficulty.
“We believe the fire passed underneath, but couldn’t confirm that,” Lolo National Forest spokeswoman Sharon Sweeney said. “There was nobody standing there and then it got dark.”
Sweeney said Tarkio fire along the Interstate 90 corridor west of Missoula burned intensely during the afternoon and evening, gobbling miles of forests, but she didn’t know how much additional acreage was involved. Before the blowout, officials said the leading edge of the fire was two miles from the BPA lines.
“When fires blow up like that…well, we won’t know until tomorrow,” she said.
I-90 fire information officer Tom Rhode said dense smoke made it impossible to determine whether the flames reached the lines or they tripped shortly after 7 p.m. MDT because of the smoke and heat.
The fire jumped containment lines on its north and east flanks and was expanding, Rhode said. “At this point, we’ve moved all crews off the lines and making sure everyone is accounted for,” he said.
Protecting the transmission line was a priority Wednesday for hundreds of firefighters battling both the Tarkio and West Mountain fire near Alberton. Before the blowout on the Tarkio fire, the two blazes had burned an estimated 4,700 acres, officials said. had burned about 4,700 acres.
The West Mountain fire was 85 percent contained, but Rhode said crews had to be pulled off lines there because of the intense smoke from the Tarkio fire, to the west.
BPA spokesman Bill Murlin said there would be “little if any interruption” in power supply if the transmission line went out of service. It actually is two 500-kilovolt power lines carrying electricity from the Colstrip power plants in eastern Montana to suppliers on the West Coast.
The lines are not running at full capacity, Murlin said Wednesday from Portland, Ore., where BPA is based. He said the agency was monitoring the fires closely and could cut electricity to the lines voluntarily.
“If the fire itself was to cause an outage, then we would have a situation where we would have to reroute the power, and we can do that,” he said hours before the lines tripped.
I-90 was open to two-way traffic after several days of restrictions imposed to protect firefighters from the hazard of passing vehicles, but only one lane for traffic moving each direction was open Wednesday, the Montana Highway Patrol said.
An order closing about 20 miles of the Clark Fork River was relaxed slightly to allow access to an unrestricted area of the river. For the most part, however, that stretch remained off-limits to the public, a safety precaution as buckets attached to helicopters scooped river water for the fires.
Also burning was the Prospect fire, estimated at 1,500 acres and described by Sweeney as “very spotty.” It burned in the Superior area. Sweeney said the burned land was broken up by large unburned areas “and we’re figuring over the next couple of days those will slowly creep together.”
Managers of a wildfire near Eureka planned to lift an evacuation order, giving the go-ahead for occupants of nine vacated houses to return home.
Occupants of at least a couple of the dwellings returned to them even as the evacuation order issued soon after the fire’s start on Sunday remained in place, said Terry Knupp, information officer for the 868-acre Camp 32 fire. It was only 30 percent contained but conditions were deemed safe for the residents who had left, Knupp said.
In the Bitterroot Valley south of Missoula, the Rockin Complex of fires in a wilderness area west of Darby had burned about 4,300 acres.
About half a dozen new fires, the smallest half an acre and the largest 50-100 acres, started Tuesday night in the Bitterroot Valley, said Dixie Dies, spokeswoman for the Bitterroot National Forest. The largest, the Signal Rock fire about 20 miles southeast of Hamilton, was visible Wednesday from U.S. 93.
On the Flathead National Forest, three fires burned in the Bob Marshall Wilderness Complex, including the 3,200-acre Kelly Point fire near the South Fork of the Flathead River. A portion of the river was closed as a safety precaution.
In eastern Montana, a 423-acre fire burned 16 miles south of Ashland in the Custer National Forest.