Landslide threat to trunk roads

The landslide at Lochearnhead saw 57 people airlifted to safety

One fifth of Scotland's main road network is at risk of landslides, according to a report.

Transport Scotland has identified 67 high-risk sites, with the A82 between Glasgow to Inverness seen as the worst.

The Scottish Government agency is looking at a better system to predict when and where landslides will occur as well as how to protect drivers.

A spate of landslides in August 2004 prompted the Scottish Road Network Climate Change Study.

What we certainly can't do is build our way out of every possible opportunity for a landslip across Scotland Stuart Stevenson Transport minister

The 2004 landslides caused major problems on the A83 near Cairndow, the A9 to the north of Dunkeld and the A85 at Glen Ogle, where 57 people had to be airlifted to safety.

Transport minister, Stuart Stevenson said: "What we've got to do is to plan what we do when landslides occur.

"We're going to be making some investments on the A87, we're likely to look at the A83, the A9 is a major route with three identified areas of risk.

"What we certainly can't do is build our way out of every possible opportunity for a landslip across Scotland.

"What we've got to do is to prepare for when it happens, make sure we've got contingency plans in place, make sure that we enable Scotland to continue running and our businesses to be supported.

'Getting wetter'

Transport Scotland said relatively few of the high-risk locations would justify the cost of major engineering.

But there could be more road protection, from straightforward drain clearing to barriers, fences and basins to collect debris.

The agency is also developing a system for better landslide prediction.

Dr Richard Dixon, of WWF Scotland, said: "It's going to get worse of course - but the real problem with the rain is that we are getting more days of heavy rain and more periods where there is consistent rain over a number of days and that builds up just the right conditions to have these muddy debris flows.

"Scotland is going to get wetter.

"We should be looking at the land use, we should be looking at planting trees which bind the soil up and we should be looking at drainage."

The road most at risk, according to the Transport Scotland report, was the A82 from Glasgow to Inverness.

A landslide on the A83 in 2007 meant a 45 mile detour for drivers

It had 16 stretches identified as being at high risk from landslides.

A 13km stretch along Loch Lochy north of Fort William was rated as the most hazardous area of all.

Other parts of the road which were deemed to be susceptible were at Glen Dochart near Crianlarich, and sections through Glencoe and beside Loch Ness.

Eleven stretches of the A83 to Campbeltown were assessed to be at high risk, including the approach to the Rest and Be Thankful in the Arrochar Alps.

In October 2007 this road was closed after 400 tonnes of soil and stone slid down the hill.

Ten sections of the A9 from Edinburgh to Thurso were rated as hazardous. These included 21km around Helmsdale in the far north, Glen Garry north of Pitlochry and a section north of Dunkeld.

Scotland's motorways also featured - 3km of the M90 from Edinburgh to Perth were rated at risk from landslides north of Glen Farg.

So was the M74 from Glasgow to Carlisle, along a small section at Elvanfoot, north of Beattock.

Other high hazard roads included the A1 between Penmanshiel and Howburn.