Drivers are warned to prepare for a two-night closure followed by a full weekend closure of the A30 between Truro and Scorrier near Redruth this week.
National Highways will be carrying out work over four dates starting on Monday.
This will see the A30 closed overnight between Chiverton and the Scorrier junction on Monday (April 17) and Tuesday (April 18).
The closure will be in force from 8pm to 6am.
This will then be followed by a full weekend road closure between Chiverton and the Scorrier junction, which will begin on 8pm on Friday (April 21) and is not expected to end until 6am the following Monday (April 24.)
National Highways said the overnight closures were so that vegetation could be cleared at various locations along the closed section of road. The official diversion routes will be well sign posted.
“The western A30 diversion route has been agreed with Cornwall Council in order to avoid low bridges.
“We’re carrying out the work overnight when traffic levels are lower to minimise disruption. Please plan ahead and allow a little extra time for your journey,” it added.
The full weekend closure will then be in place to allow a range of works at various locations along the closed section of road.
This includes the construction of a new road crossover, in preparation for switching to a contraflow system in May.
“We are also excavating the road to undertake utility diversions, including a trench across the carriageway.
“A section of the B3284 south of the A30 will also be closed during the weekend for road realignment works,” added National Highways.
Landlocked residents whose only way out is via the A30, and who need access during the night, can contact the Chevron Traffic Safety Control Officer via the helpline number 07918 586974.
A resident's pass will be provided, with a safety vehicle escorting the driver out of the closure area.
The work is part of a wider £330 million project to fully dual the A30 between the Chiverton Cross and Carland Cross roundabouts. The project is predicted to end either late 2023 or at some point in 2024, depending on the progress made.
