30 November 2020

Developing problems at Rest and Be Thankful

Posted by Dave Petley

Developing problems at Rest and Be Thankful

In recent months I have posted on a number of occasions about the developing landslide problems at the now infamous Rest and Be Thankful in W Scotland. Unfortunately, the landslides there continue to develop, causing increasing levels of disruption.  Last night both the A83 itself and the Old Military Road diversion were closed once again as a precaution.  We are in a spell of repeated rainfall events in the area; with the material being so unstable on the slope the roads cannot be safely operated in the dark (and of course the nights are very long in Scotland at this time of the year).

There is an excellent stakeholder presentation about the problems at Rest and Be Thankful on the Transport Scotland website (it is a PDF).

BEAR NW Trunk Roads have been proactive in providing information as to why these road closures are needed.  They are aware that these problems are causing substantial disruption.  On 25 November they tweeted a drone video of the site above the road that is now causing so much concern:

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This video shows the range of landslide types now active at Rest and Be Thankful.  Of particular interest is the landslide in the centre of the video, which is clearly retrogressing and releasing a large volume of debris:-

Rest and Be Thankful

The state of the landslide at Rest and Be Thankful in Scotland. Still from a drone video tweeted by BEAR NW Trunk Roads.

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Note the shallow flow to the left as well, the source of which lies much further up the hillside.

The main landslide highlighted above involves a large volume of material, and it is actively destabilising more.  BEAR NW Trunk Roads has also tweeted these time lapse videos showing movement of material in the main landslide during heavy rainfall:-

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The second of these videos shows the full magnitude of the challenges faced by the geotechnical engineers and engineering geologists at this site, and the amount of material that could become involved.  Given the terrain, this is not a problem that is going to be fixed anytime soon, although works are underway to try to minimise the impacts.