State Highway 35 between Ōpōtiki and Gisborne is now closed.

SH35 at Motu river collapsed along the centre line on Wednesday evening with the eastbound lane falling into the river.

"Traffic had been reduced to a single lane due to the large crack in the road since Monday, July 18," says a Waka Kotahi NZ Transport Agency spokesperson.

"The detour for vehicles (except over-dimension vehicles) is SH2 through Waioeka Gorge but Waka Kotahi advises caution. Traffic is reduced to a single lane due to underslip at 7km west of Matawai."

In a statement released on Wednesday, NZTA says the regions highway networks have been hit hard.

"The recent severe weather with slips, drop outs and flooding in a number of locations. Crews are actively monitoring the network to ensure the safety of all road users."

Emergency works are being carried out at different locations around the region.