A washed-out bridge on the East Coast south of Ruatoria is likely to remain impassable until at least Tuesday. Meanwhile, communities north of the town are cut off.
The Transport Agency says State Highway 35 in the East Cape region between Tokomaru Bay and Ruatoria is closed because the approaches to a bailey bridge over a creek have been washed away.
People needing to get out are being advised the possible route is through Opotiki in Bay of Plenty.
NZTA says people in communities as far north as Hick's Bay need to start preparing now for the disruption in the next few days.
The agency says it is working with logging companies in the area to help them avoid disruption.
Equipment is being shipped from Napier and the Transport Agency hopes reapirs can begin on Sunday morning.