A section of the A76 between Thornhill and Sanquhar is scheduled to be rerouted to avoid an unstable riverside embankment.
The route, just south of Enterkinfoot, has been reduced to a single lane with temporary traffic lights for almost four years due to the landslip risk.
Operator Scotland Transerv has now revealed a £2.8m blueprint to realign the road.
The six to eight-month construction programme could start next year.
John Murray, the secretary of Sanquhar and District Community Council, said the solution was probably the best option available.
He said that people who had been campaigning for action would not rest until the work was under way.
"It is just a case of hoping that they are going to stick to their word," he said.
"They are saying now that the money is in place to do the new stretch of the road."
However, he said there would still be issues of land acquisition and legal process to be resolved.
Announcing the preferred option for the works, Transport Minister Humza Yousaf said he was delivering on a promise given at a summit in the region.
"The geography of the area presents significant challenges to engineers, but positive work is already under way with the local landowner to transfer ownership of land to Scottish ministers to allow this work to go ahead," he said.
"This investment will help provide more reliable journey times for motorists and businesses along the full length of the A76, as well as improving connectivity in the region and further afield to Northern Ireland."