The California Geologic Survey has published a new map of landslide susceptibility for the entire state of California. It addresses only deep-seated landslides, not shallow slides such as debris flows. The criteria used for developing […]
A section of Route 30 in East Pittsburgh, Pennsylvania has been destroyed by a landslide, and the road could remain closed for several months. An apartment building down-slope has also been destroyed, although all residents were […]
The City of Pittsburgh Pennsylvania has recently started a nearly $1M landslide remediation project on the City’s north side, but it is only one of nearly 20 landslide sites affecting public rights of way being monitored […]
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
___________
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)
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
___________
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)