The Pahiatua Track will be closed tomorrow for three days, from 8.30am to 2.30pm each day.
Regional transport systems manager Mark Owen said the road needed to be inspected on-foot so that NZTA can determine the condition of the road and whether any repairs are required in the future.
"We will also complete minor maintenance works during the closure, including small pavement repairs, edge marker posts replacement and sign cleaning.
"These sections of road are narrow, so a full closure is necessary to provide a safe working environment for the inspection team and to protect road users.
"There will be a detour route via Saddle Road, which will add an extra 16km or around 20 minutes to your journey between Aokautere and Pahiatua. We advise all road users to plan ahead and allow extra time for their journeys.
"We acknowledge this work is disruptive, so the Transport Agency would like to thank road users for their patience and understanding while we carry out this important work for the community."
Access to all local properties will be maintained throughout the closure, which will be managed by the contractors.
Keep up to date with: Traffic updates: nzta.govt.nz/traffic, Facebook: facebook.com/nztacni, Twitter: twitter.com/nztacni, Journey planner: journeys.nzta.govt.nz or phone 0800 4 HIGHWAYS (0800 44 44 49).