Over the past week there has been devastating flooding and landslides in the Gansu Province of China, particularly in Zhouqu county. According to BBC, the latest death toll numbers are at 1,239. Here are some […]
Devil’s Slide is an infamous landslide along California’s Highway 1 or Pacific Coast Highway near Pacifica, just south of the San Francisco Bay area. Caltrans’ Devil’s Slide Tunnel project is an effort to bypass that slide and make the heavily traveled roadway safe for drivers and to eliminate the maintenance and traffic hassles caused by slope failures blocking the road. We first covered the project back in September of 2007 when the tunnel portion of the project commenced. In that post, you can find a Google Earth KML File showing the location of the tunnels and the new bridges associated with the project. In this post, I’ll provide you with some updated progress information as well as some background on the geotechnical and other aspects of the project. More links and videos are at the end of the post. (Photo by Kim Komenich, San Francisco Chronicle). […]
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)
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