The works are being carried out between the Esk Valley and Tarawera.
Drain maintenance is also being undertaken on the northern side of the Titiokura Saddle about 7km north of Te Pohue.
On State Highway 50 between Napier and Dannevirke scattered clearing of minor slips is under way between Fernhill and Takapau and minor delays can be expected at all sites.
There may also be occasional delays due to a tree felling operation being carried out 4km south of Onga Onga.
Motorists using State Highway 38 between Wairoa and Waikaremoana are advised to drive with care through the Makapua Stream Bridge stretch 22km west of Frasertown.
A temporary bailey bridge structure with unsealed approaches is now in place alongside the bridge which was damaged by a falling tree last month.