Repairs under way on slip which closed State Highway 4 near Raetihi

The highway was closed on Saturday evening following a washout near Burrell Rd, 50km south of Raetihi. Photo / Bevan Conley

The Parapara Road on State Highway 4 will remain closed until at least Thursday.

The highway was closed on Saturday evening following a washout near Burrell Rd, 50km south of Raetihi.

Waka Kotahi NZ Transport Agency's regional transport system manager, Ross I'Anson, said the road had washed out on both sides, leaving about 300mm of road in the middle.

"Repairs involve excavating the road out, placing a new culvert and reinstating the lanes."

He said SH4 between Whanganui and Raetihi was narrow and the road needed to be closed for crews to safely complete the repairs.

Information on an opening time is expected by Thursday evening.

"We are hoping to have the road open on Thursday, depending on weather," I'Anson said.

The detour is expected to add up to 90 minutes depending on the route taken and the destination.