The geotechnical investigations and report are complete for the US 89 Bitter Springs Landslide south of Page, Arizona. ADOT published a news release with the results of Kleinfelder’s geotechnical investigation and a link to their geotechnical report. The recommended mitigation for the 1,200 foot long, 135 foot deep landslide is to cut into the uphill slope and move the road approximately 60 feet and to use the resulting material to construct a gravity buttress at the toe of the slide. Other options considered but rejected were rerouting the road, some form of active stabilization using a retaining wall, and simply closing the road. The repairs are estimated to cost $40M and take approximately 2 years to complete. The video below shows an interview with Steve Boschen, Deputy State Engineer for Arizona describing the alternatives that were considered. [Source: Check out the full ADOT Press Release and download the report via Arizona Geology Blog. Image: ADOT]
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