The Scottish Government has awarded a £5.5m contract for ground investigations at the Rest and Be Thankful.
The pass, on the A83 in Argyll and Bute, has been hit by landslides and flooding in recent years, forcing ministers to seek a long-term solution.
Last year, it was agreed a shelter would be built above the road to protect it and passing cars from debris caused by landslides.
While a medium-term solution to the issues facing the road includes using the adjacent Old Military Road as a diversion, with improvements including debris-catching fences being put in place.
The contract has been awarded to Structural Soils, with investigations due to start next month and inform the design process for the long-term solution.
Transport Secretary Fiona Hyslop said: “The Scottish Government remains committed to delivering a long-term solution to the landslip risks at the A83 Rest and Be Thankful.
“The announcement last June of the preferred route option for the long-term solution was a significant confirmation of our commitment to improve the route.
“The design work for this is being progressed at pace with a view to publishing draft Orders by the end of this year.
“The ground investigations to begin next month will provide essential information to inform design development of the preferred route option.”
The Transport Secretary added: “At the same time, we are progressing our plans to increase the resilience of the temporary diversion route along the Old Military Road.
“The first phase of the work to realign the southern end of the route, reducing the risk of flooding, commenced construction in December and the new link road is now complete.
“The ground investigations to inform future phases of the Medium Term Solution are already under way and we will then look to start further construction works later this year, subject to obtaining the necessary consents.
“When completed, the work on the Old Military Road will increase the resilience of the temporary diversion route by reducing the likelihood of landslides impacting it. These improvements will mean more certainty for locals and road users if the A83 has to shut due to adverse weather conditions.
“All of this underlines the Scottish Government’s commitment to work with local communities and key stakeholders to ensure that Argyll & Bute remains open for business.”
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