Tilt meters installed on an unstable section of the A83 Rest and Be Thankful route triggered an alarm and led to closure of the road ahead of a landslide event yesterday.
Following closure of the route Transport Scotland’s trunk road operator Scotland TranServ investigated the cause of the alarm and confirmed that a slip had occurred on the hillside above the road. Transport Scotland said that the slip, involving 20 to 30t of material, had not reached the carriageway but TranServ observed tension cracks above the slip suggesting further movement is likely.
Transport Scotland said that the road would remain closed until at least Friday morning and the decision to reopen the route will be based on whether an inspection of the hillside shows continued instability or not. Equipment to clear any slipped material from the road has been placed on standby.
The tilt meters that activated the road closure were installed at the site after landslides in 2007 and 2009 and were part of a £700,000 package of work that also included installation of flexible flow netting, a new culvert and drainage systems.
The new landslide comes less than two weeks after Transport Minister Keith Brown announced plans to invest £1M to develop additional contingencies and mitigation work to help deal with future landslips. This is in addition to the recently commissioned study which is investigating the feasibility of longer term options.