Allegations: Oregon Not Forthcoming With Landslide Hazard Information
Geologic Hazards
GeoGirl – Fighting Geohazards Since 2016!
The comic book superhero GeoGirl fights to protect the public from geohazard villains such as Dick Clay and Lance Lied! These entertaining geotechnical comic books are developed by San Francisco Bay Area geotechnical engineering firm […]
Project Related
Devil’s Slide Tunnel Update and First Attempts to Tame the Landslide
The Devil’s Slide Tunnel project is on schedule and on budget according to a news story at ABC7News.com from earlier in June. The video (shown after the break) has a few nice shots showing rock bolting, soil nailing at the portals, and the geologic mapping and laser scanning that happens at the tunnel face.
I also came across a very neat article about how the Ocean Shore Railroad Company was the first to try to cut into the slope along what is now PCH 1 at the Devil’s Slide back in the early 1900s. They were trying to connect the then rural farming community of Half-Moon Bay with San Francisco. The railroad fought the reoccurring landslide and serious rockfalls. Ocean Shore Railroad went bankrupt in 1922 and pulled up its rails, making room for the current highway. (Photo at left from halfmoonbaymemories.com)
Geologic Hazards
US 89 Bitter Springs Landslide near Page, Arizona
Sometime before 5am on February 20, a landslide occurred on US 89, about 25 miles south of Page, Arizona near the town of Bitter Springs. The area is known as the Echo Cliffs, and is […]
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Clatskanie Landslide
Dear geo blogger,
My take on this slide is that the old railroad crossing or road crossing that held up the water for the Clatskanie Event on or about Jan 11, was not “put to bed”. The crossing should have been destroyed and the abutments pulled out of the channel. The slide volume and extent of travel of the subsequent debris flows would have been much smaller and shorter.
I served for a year as an ERFO Hydrologist at the Detroit Ranger Station, up the Santiam Canyon from Salem in 1997 and 1998. An about-to-retire civil engineer, Bill Day, used the “put to bed” term and practice. He also said something else that was useful, “it takes trees to be twenty years old or more before their root systems hold back natural landslides. The trees on the reforested property above the Clatskanie debris flow section were not that old.
I agree with Bill Burns and, to reinforce his statements, I like what he said about the recent spate of landslides.
John Rehm
Registered Geologist G1137
Salem, Oregon
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Note: This is a Opinion based on literature (Dryness, c. 1964), my MS Thesis published on the Rutgers University Geosciences website, and professional experience under registered engineer supervision by Bill Day (1997-1998 (just in case OSBGE is reading this)
Put to bed
Thanks for your insights John. I’ve never heard the term “put to bed” before, but I couldn’t agree with you more. And the factoid about tree root systems seems like a very useful rule of thumb. — Randy Post (aka Rockman)