Work to connect the A1 near Grantham to the B1174 for the project will start in September 2019.
The scheme's second phase, which is expected to take two years to construct, will see a bridged junction / underpass built connecting the A1 with the B1174 relief road roundabout built in 2016.
Traffic management planned for the scheme is as follows:
- Lane closures on the A1, between the A607 and Little Ponton junctions, from 8pm to 6am starting in early September for a month to allow for widening works.
- A 50mph enforced speed restriction will also be implemented at this time and will remain in place for the remainder of the scheme.
- Northbound traffic will be moved to the southbound carriageway, and southbound traffic will be moved to the newly-constructed widened section of carriageway from early November for seven months.
- This work will allow half of the new bridged junction to be built.
- Following completion of the first half of the new bridged junction, the A1 will be moved onto it to allow for the second half to be constructed over eight months. During this time, the A1 will continue to run on four lanes.
- Additional lane and carriageway closures will be required throughout the course of the project to allow for critical construction operations to be carried out safely. Date and details of these closures will be announced once dates have been confirmed.
Cllr Richard Davies, executive member for highways, said: "It's taken some time to get here, but we're now less than a month away from getting the next phase of this huge project underway.
"Over the past two months, Galliford Try has been working hard on site sorting out the logistical essentials for carrying out a scheme this size, including constructing a site compound, setting up storage areas for materials and building up a site team.
"When building any piece of new infrastructure, there will inevitably be some disruption. But all of those involved in the project, including the county council, Highways England and Galliford Try, will be doing everything they can to keep it to an absolute minimum.
"Once work starts on the A1, we ask that those affected to remain patient and remember that any short-term disruption will be well worth it in the end once the relief road is built."
The Grantham Southern Relief Road project is being led by Lincolnshire County Council and supported by South Kesteven District Council, Greater Lincolnshire LEP, Highways England, Department for Transport, Network Rail, Homes England and local businesses.
For the latest news on the Grantham Southern Relief Road, visit www.lincolnshire.gov.uk/majorprojects