Two month programme of work starts on Monday.
Major repairs are being made to the A361 Braunton Road over the next two months.
The ‘essential’ reconstruction and resurfacing work is due to start on Monday and is expected to be completed by Wednesday, March 25.
Traffic lights, poles and electrics will also be replaced at Pottington Industrial Estate in Barnstaple, at the junction of the A361 Braunton Road, Pilland Way and Chaddiford Lane.
Although roads will not be closed completely, delays are expected and motorists are being advised to allow extra time for their journeys.
A Devon County Council spokesperson said a combination of lane closures and temporary traffic lights would be put in place while the work is carried out.
Local access will be maintained for residents.
The resurfacing scheme, carried out by contractor Lafarge Tarmac, is weather dependent and the schedule may be subject to change.