A toolkit of actions that roads authorities could take when rain gauges suggest a risk that a landslide might occur is to be produced.
Consultants led by TRL Scotland are examining the link between rainfall levels and the likelihood of a landslide hitting the trunk road network as part of research for the Scottish Executive.
The project to develop understanding of where the greatest hazards and risks are on the trunk road network, and to develop a system for managing them.
‘We want to be able to be more proactive, to be able to say, “We have the conditions which mean there may be a landslide”, and to act on that,’ said Mike Winter, researcher at TRL.
The toolkit would outline actions which roads authorities could take, including switching on a variable-message sign to warn drivers, sending out patrol teams on to the network or, in extreme circumstances, closing a road likely to be affected.
The problem is that knowledge of the relationship between landslide occurrence and particular rainfall levels in certain locations ‘will take time to develop’, according to Winter.
To gather new information on the link, rain gauges will be installed on the A83, a route where landslides occur frequently. And while past information on the rainfall that led to previous landslides is imperfect, the consultants are exploring the possibility of undertaking a back analysis of available rainfall data and correlating this with known landslide events. The work is due for completion by spring 2007.