Part of State Highway 30 near Kawerau will be closed for 12 hours tomorrow as railway lines over the road are upgraded.
Drivers travelling between Rotorua and Whakatane between 6am and 6pm should expect short delays of up to 10 minutes due to traffic detours.
The New Zealand Transport Agency's Bay of Plenty highway manager Brett Gliddon said the majority of motorists would be detoured through Kawerau.
A detour via Onepu Springs Rd will also be available.
"A full road closure is required to complete the works as it is not possible to line the rubber panels and track if carried out one lane at a time."