Drivers in and near Grantham will face a week of overnight southbound and northbound A1 closures from Wednesday as part of the Grantham Relief Road works.
A full night-time closure of the southbound A1, between Harlaxton and Little Ponton, will be in place from Wednesday, February 10, between 8pm and 6am for seven days.
The diversion route will be via the A607 at Harlaxton to the A606 to A1 at Stamford.
The first three nights of work will allow the final 14 and 20-tonne bridge beams to be delivered and lifted into place for the new A1 connection to the B1174.
The final two nights of southbound closures, along with three evenings of night-time closures on the A1 northbound, between Little Ponton and Harlaxton, will start on Wednesday, February 17.
This will allow Galliford Try to safely carry out additional works close to the A1.
The diversion route for the northbound closures will be via A606 at Stamford to A607 to A1 at Harlaxton.
Councillor Richard Davies, Executive Member for Highways, said: “The concrete bridge beams being delivered and installed are key components of Grantham’s new relief road.
“As part of this work, a 250-tonne crane will be set-up on-site to lift the beams off the delivery lorries and into place.
“Once in place, Galliford Try can make a start on building the new bridge deck ahead of finishing the second half of the A1’s new connection with the B1174 and completing phase two this summer.
“We’ll be working closely with Highways England to minimise disruption, including making sure the A1 is open during the day.
This is an incredibly important part of the relief road project, so I want to thank everyone in advance for their patience.”