An article by the NZ Herald reports that recommendations for slope monitoring and early warning made by a geotechnical consulting firm in a report 2 years before the initial failure were not adopted by Auckland Transport. The Birkenhead landslide initially took out 25 parking spaces in a retail area in October of 2017, and a larger landslide in November of the same year took out a micropile or other drill rig working to stabilize the site. Local officials defended the decision, indicating that they instead opted for regular site visits and visual observation of cracks noted in the report. The initial recommendations by GHD Engineers included the monitoring as a minimum, and also recommended several stabilization options in the range of $500k. The current estimates to repair the landslide are $14M to $24M.
In case you missed the background on the Kilbuck Landslide (or here or here), it happened in Kilbuck Township, PA back in in September of 2006. To deal with the political hot potato and media nightmare, Wal-Mart bought out the developer on the unfinished property and began handling remediation of the slide itself. Now, it appears as if they want their money back from the developer! Read on for more details.
Earlier this month, there was a massive slope failure on the "Sea to Sky" highway in British Columbia. It is interesting to note that this same area had a large rockslide in 1965, and a photo of this failure is featured on the cover of the classic text, Rock Slope Engineering by Hoek and Bray. The media played up the aspect that this highway is one of the only ways to access the site of the 2010 Winter Olympic games hosted by Vancouver.
The composite image above shows the book cover and the recent rockslide event (Photo credit: Erik Eberhardt of the University of British Columbia by way of Dave’s Landslide Blog). Dave has done a fabulous job collecting photos, facts and links from around the web. In a follow up post, he added some additional photos and discussion. I recently came across an article that described how the highway originally was slated to have a tunnel bypassing the slide, but that the price tag of $200 million (CAN?) for a 1-km stretch killed the project.