Landslide and Debris Statement from Oregon Geology

Landslide WarningCOOS COUNTY, Ore. – The National Weather Service has issued a Flood Watch for the Coquille River at Coquille and the South Fork Coquille River at Myrtle Point.
The Flood Watch is in effect February 13 through February 17 for the Coquille River and February 15 through 16 for the South Fork Coquille River.
Landslides and debris flows are possible during this flood event. People, structures, and roads located below steep slopes, in canyons, and near the mouths of canyons may be at serious risk from rapidly moving landslides.
According to the Oregon Department of Geology and Mineral Industries (DOGAMI), caution should be used when traveling over the mountains during this time. The most dangerous places include:
* Canyon bottoms, stream channels, and areas of rock and soil accumulation at the outlets of canyons.
* Bases of steep hillsides.
* Road cuts or other areas where slopes of hills have been excavated or over steepened.
* Places where slides or debris flows have occurred in the past.
Debris flows are rapidly moving, extremely destructive landslides. They can easily travel a mile or more, depending on the terrain. They will contain boulders and logs and transport those in a fast-moving soil and water slurry.
Some areas are more hazardous than others when the danger of landslides is high. If there is a flood warning, stay away from the river. Stay away from steep slopes during intense rainstorms. Knowing ahead of time where the danger areas around your home for potential landslides might be is the first step in being prepared.
Follow these steps:
* Stay alert. Listen to the radio, TV, or a weather radio for flood watches, which include the potential for debris flows and if told to evacuate, do so immediately.
* Listen for unusual sounds that might indicate moving debris, such as trees cracking or boulders knocking together. A trickle of falling mud or debris may precede larger landslides.
* If you think there is danger of a landslide, leave immediately.
* If water in a stream or creek suddenly turns muddy or the amount of water flowing suddenly decreases or increases, this is a warning that the flow has been affected upstream. You should immediately leave the area because a debris flow may soon be coming downstream.
* Assume highways are not safe. Be alert when driving, especially at night. Don’t overdrive your headlights. Embankments along roadsides may fail, sending rock and debris onto the road.
* Landowners and road managers should check road drainage systems and conduct needed maintenance in case the predicted heavy precipitation does occur.
Cleaning up after landslides can also be hazardous. When it is wet outside, be careful when cleaning up the mess. A small mudslide can actually be part of a larger landslide. Cleanup should not be done until after the storm.

This entry was posted on Tuesday, February 11th, 2014 and is filed under Local News, Press Releases, Weather Warnings.