Heavy rainfall has caused disruption and damage on roads across Scotland, with severe weather warnings exacerbating a new closure of the A83 at Rest and Be Thankful.

A huge landslide blocked the road last week, with what trunk road operator BEAR Scotland described as ‘car-sized boulders'.

The landslide occurred on 4 August after around 100mm of rain fell in the Argyll area. BEAR Scotland said the landslip started around 200m above the A83 but split into two main channels as it spread out in a ‘fan effect' down the hillside.

‘One of the channels filtered into one of the landslip mitigation catch-pits which prevented around 2,000 tonnes of material from reaching the road, with around 1,500 tonnes of debris reaching the carriageway at the second channel. Car-sized boulders also reached the roadside in the debris. A further 2,000 tonnes of material was washed onto the Old Military Road.'

BEAR said the landslide is thought to have moved around 6,000 tonnes of debris down the hill, ‘one of the largest landslips in recent times'.

The Old Military Road is used as a diversion when the A83 is closed.

Although the diversion route reopened at the weekend, it has been closed overnight, including from 9pm on Wednesday (12 August) until 6pm on Thursday.

On Wednesday, Eddie Ross, BEAR Scotland's North West Representative said: ‘Further weather warnings for thunderstorms are in place across large areas of Scotland throughout the day into the evening, which have the potential to bring sporadic heavy localised rain showers.

‘We need to prioritise safety of road users and with the amount of loose debris still present in the channels we've decided to close the route overnight for a third night as a precaution and in the interest of keeping everyone safe.

‘Designs are being finalised this week which will allow us to have a clear understanding of a timeline to completing the repair work and safely reopening the A83.'

Following the closure, the leader of Argyll and Bute Council called on the first minister Nicola Sturgeon to make an immediate commitment ‘to deliver a permanent solution after a decade of disruption'.

Cllr Aileen Morton said: ‘This is now the second landslide of the year that has closed the Rest and Be Thankful and resulted in disruption to a major trunk road causing havoc for our communities, businesses and visitors. It is abundantly clear that mitigation measures taken by Scottish Government have yet again failed the people of Argyll and Bute.

‘Taking such a shilly shally approach is simply no longer acceptable and we, as a council are asking again for a permanent solution to be identified, funded and delivered as a matter of urgency. The issues on the Rest and Be Thankful have been debated, investigated, patched up and largely ignored for the last decade and we still find ourselves in this same position again.'

Heavy rain in the early hours of Wednesday also damaged the carriageway of the A68 – another Scottish Government trunk road – with a large crater appearing in the road at Fala Dam.

A full closure was put in place with a signed diversion route of 27.5 miles for both southbound and northbound traffic – adding an extra 7.5 miles and 13 minutes to journeys.

Joanne Turner, Amey's principal civil engineer with the South East Trunk Roads Unit, said: ‘Geotechnical investigations into the extent of the damage and the necessary repair are ongoing, and further updates will be provided by Transport Scotland and the relevant operating company.

‘A timeframe for the repair will be developed once investigations are completed and more information will be provided in due course.'

The reference to the relevant operating company reflects the fact that from Sunday, the South East Trunk Roads contract, which has been operated by Amey since 2014 will transfer to BEAR Scotland. Amey will take over the South West contract from Scotland TranServ.

A Transport Scotland spokesperson told Highways: ‘The handover should have no impact on the repairs as Amey and BEAR are working on the project together.'

The damaged section of roads is within the Scottish Borders. A spokesperson for the Scottish Borders Council told Highways that no damage had been caused to its roads.

However, roads in Fife, Aberdeenshire and Perthshire were closed with the town of Stonehaven in Aberdeenshire, near the site of Wednesday's fatal train derailment, also flooded.