Motorists face disruption and a complete road closure of the main route between Horncastle and Louth over the coming days.
The News can reveal part of the A153 north of Horncastle will be completely re-built in a scheme financed by Lincolnshire County Council.
Work is scheduled to start on Monday July 14 and the road - one of the busiest in the area - will be closed between 7pm and 7am for up to two weeks.
The recommended diversion is via the A158, Caistor High Road and the A157. That route is almost eight miles longer and will take almost twice as long (45 minutes).
The section of road involved is a 1.2km stretch south of West Ashby village, near to the junction with Docking Lane.
A County Council spokesman said: “We’re basically re-building the road. The foundations are crumbling.
“We apologise for any delays but the work has to be done. The new surface will last 20 years.”
Advance warning signs are on display.
Van driver Nigel Larder, who lives in Horncastle and works shifts for a Grimsby company, said “It will mean more miles and more time.”