Remote slope stability infrastructure monitoring

In the spring of 2005, a landslide damaged or destroyed parts of 12 miles of the Beartooth Highway, a federally recognized National Scenic Byways All-American Road. Since then, the Montana Department of Transportation (MDT) conducted significant repairs to the affected areas. However, these efforts did not fully address the underlying stability issues, and slope movement continued to threaten the scenic highway.

The same environmental conditions that create the tremendous natural beauty that entices people to use the highway also pose significant challenges to maintaining stable ground conditions and conducting repairs. The Beartooth Highway passes through three national forests, the Absaroka-Beartooth Wilderness, and provides the only access to the northeast entrance of Yellowstone National Park. With a maximum elevation of just under 11,000 feet (3,353 meters), it is the highest highway in both Montana and Wyoming. Due to ice and snowfall, the road is normally open only four to five months out of the year, and it is during this short period that all repair work must be completed with an eye to maximizing access to Yellowstone.

These factors led the MDT to take a proactive approach and implement a program to collect ground stability data around the road in order to prevent landslides before they happened rather than wait to repair damage after the fact. They contracted Shannon and Wilson to design and install the system, which would include six high-precision GPS sensors to monitor surface movement and a Measurand ShapeArray SAAV to measure subsurface movement. The sensors were connected to a sensemetrics’ Thread to collect and remotely stream near real-time data to the MDT. The system’s simplicity made it cost-effective to put in place, and the data it produces provides savings by allowing them to intervene before trouble strikes.