Oregon’s Wildfire-Damaged Forests Vulnerable to Landslides

Another week of rain and snow could heighten landslide risk for eastern Oregon’s fire-damaged forests.

Wildfires have stripped away water-soaking vegetation in areas like Canyon Creek, leaving hillsides particularly vulnerable to landslides, reported the East Oregonian.

“You guys do have steep slopes and places where the ground has moved in the past,” said Ali Ryan Hansen, earth science information officer for the Oregon Department of Geology and Mineral Industries. “Whatever people are doing on a day-to-day basis, they need to be thinking about the landslide hazard.”

Staying alert for landslides means listening for telltale sounds like cracking trees or boulders knocking together, said Hansen. She said water that suddenly turns muddy or suddenly changes flow could also indicate a landslide upstream.

Intense rainfall is a common landslide trigger. The National Weather Service in Pendleton is forecasting a chance of rain or snow every day this week and as much as 2 inches of precipitation in the mountains.

Snow could accumulate at higher elevations and lower elevations could see an additional half-inch to inch of rain, according to Hydrologist Marilyn Lohmann.

Treatments to stabilize the ground after the Canyon Creek Complex fire appear to be holding up in recent storms, according to Malheur National Forest fire staff officer Roy Walker. Helicopters dumped wood mulch on the hillsides and placed log jams over portions of creeks in the area.

Walker said staff will continue to monitor the treatments into the spring.

“It might take a little warmer weather and little more rain to really have an effect,” he said. “Those early thunderstorms are a big concern, too.”