The B3212 between Farrants Hill and Perridge Cross will be closed for around five days in order to carry out drainage repairs.
There will be road closures in place for the majority of this work and a signed diversion will be in operation.
The diversion route will be via B3212, Ide Village Road, A30, A38, B3344, B3293 and B3212, and the same going in the opposite direction.
A spokesperson for Devon County Council said: ‘Diversions are a recommended route only, using roads of equal category to that on which the road works are taking place.
‘They’re not compulsory, and people with good local knowledge of alternative routes are able to use those if they wish to.
‘Please note that the works are dependent on weather conditions and therefore the duration may vary.’
The spokesperson said the essential works will ensure that surface water can drain away from the road’s surface and are needed in order to maintain the road in a safe condition and maintain the structural integrity of the road’s drainage system.
They added: ‘Due to the scale of the repair, and in order to ensure the safety of our workforce, this work can’t be carried out without a road closure.
‘We apologise for any inconvenience these essential works may cause and would like to assure you that we are doing our best to minimise disruption.’