Rain easing up but slide danger continues

Having trouble viewing this email? View it as a Web page.

Rain creates slide threats, other concerns around Oregon

Jan. 13, 2021

Contacts:

Don Hamilton, Portland area, 503-704-7452

Lou Torres, Coast and Willamette Valley, 503-559-7118

Heavy winds and rain have produced a variety of road hazards including standing water, flooding, downed trees and powerlines. But another major threat in the days ahead will come from rain-soaked hillsides that threaten to slide onto Oregon roads.

Even as rains let up, saturated, unstable soils remain, aggravating the potential for slides. On Wednesday we started assessments, including aerial observations, to study the extent and nature of the threat.

The slides have been taking place in areas of the state accustomed to slides in heavy rain, including the Columbia River Gorge, rivers along the Coast Range and in the Cascades.

Visit TripCheck.com for the latest road conditions and closures.

The slide threat will be greatest on roads with steep hillsides. Here are some tips for drivers:

  • Be especially alert. Bridges may be washed out, culverts overtopped and boulders may be dislodged.
  • Don’t drive through high water. You may not know if it’s dangerously deep.
  • Watch for sunken and cracked roads and leaning utility poles, trees or fences.
  • Listen for unusual sounds that might indicate moving debris, such as trees cracking or boulders knocking together. A trickle flow may precede a much larger event and slides can develop quickly.
  • If near a river or creek, be alert for sudden changes in water levels or if the water changes from clear to muddy. Such changes indicate activity upstream and you should be prepared to move quickly.
  • Be especially alert in areas burned by the September 2020 wildfire, where the threat of slides is increased.
  • Get away from a slide. More may be coming.

Remember, slides vary widely in size and can move at slow or very high speed depending on slope angle, water content, and type of earth and debris flow.

I-84 Wednesday morning