Wet weather holds Oregon fires in check, but increases landslide risk
by Erin Ross, Oregon Public Broadcasting | posted: September 26, 2020
Crews have made more progress toward containment on the Riverside and Beachie Creek fires, aided by wet weather, according to the latest official updates Thursday. Fires were burning strongest in dry debris under tree canopies.
Strong winds pushed the Lionshead Fire toward the east, and started spot fires along the fire’s perimeter. Although it grew slightly, it remains 15 percent contained. Most containment lines were around the communities of Detroit, Idanha, and Breitenbush, where crews are continuing to mop up hotspots. Crews are preparing for potential future fire activity by working with teams from the Riverside Fire to connect forest service roads that could ultimately be used as containment lines.
Winds stoked the flames on the Holiday Farm Fire, but most of the areas burning were towards the fire’s interior, and the fire did not grow. Air crews were instead diverted to other fires in the area.
Doug Grafe, the chief of fire protection for the Oregon Department of Forestry, told reporters Wednesday that the combined Slater and Devil fires burning in Northern California and Southern Oregon are the state’s biggest concern. The fires started in Northern California, and have slowly moved towards communities in Oregon’s Illinois Valley to the north, and Oregon Caves National Monument to the east.
No rain fell on the burned area yesterday, but heavy winds invigorated the fire and caused it to jump containment lines on Wednesday and Thursday. Crews were able to catch the new spot fire quickly. The fire was 24 percent contained and over 152,000 acres. Portions of Highway 46, which approaches the Oregon Caves National Monument, were closed.
Burned areas in the Willamette Valley received 1 to 2 inches of rain over a 24 hour period starting Wednesday. While that aided in suppression efforts, it has posed problems for crews working to restore utilities and road access to the area.
Officials working the Riverside Fire said debris continued to fall onto Highway 224, spurred by ongoing rains.
“One of our concerns right now is the 224 road,†said Ralph Lucas, who works on the Riverside Fire incident management team, “We have a lot of infrastructure in there that’s damaged, as far as electrical infrastructure. And then the road system in there continues to receive debris and rockslides.â€
A hydrologist out of Medford has been working with the incident meteorologist on the Holiday Farm Fire, and surveyed the area. While he found no immediate risks for large landslides, the fire destroyed undergrowth and weakened tree roots, and loosened debris continues to fall. The areas around Gates Creek and Quartz Creek areas sustained the most damage, and small landslides are expected to impact roads in the area through the winter.
Highway 138 through the Archie Creek fire opened Thursday. However, officials caution that the region is still hazardous, and downed trees, rockfall, and debris flow remain potential hazards. Motorists are asked to drive carefully, be prepared to encounter hazards, and to avoid stopping or pulling over to the sides of the road.
Cool, wet weather is expected to continue for the weekend, but next week, that might change. A series of fronts are expected to move over the area tonight through Saturday, and temperatures will remain cool. But come Sunday, a high-pressure ridge is expected to bring unseasonably warm temperatures back into the area. Light, easterly winds will also bring smoke back into western parts of the state.
Temperatures in the Willamette Valley are expected to reach the low 80s, while parts of Southern Oregon will see the return of temperatures in the mid- to high 90s. In the southern coastal range, winds could be stronger, especially along the peaks of the mountains. That, combined with “Chetco-effect†or “Brookings effect†heat headed towards the coast, could increase activity in the Slater-Devil Fire. In previous years, such weather drove the Biscuit Fire and Chetco Bar Fire to grow rapidly.