Major milestone for restoration of State Highway 4 Parapara Rd between Whanganui and Raetihi

The Auraki Stream road retreat project involves the relocation of SH4 away from where the Mangawhero River slip occurred in June 2015. Photo / Supplied

A major milestone in the ongoing repairs to State Highway 4 Parapara Rd, north of Whanganui, has been reached with a new section opening on Thursday.

In June 2015 major flooding in the Whanganui region caused substantial damage to parts of the road.

Since then Waka Kotahi New Zealand Transport Agency has completed work on five main repair sites, as well as the site of a subsequent slip at Te Oreore in 2019.

One of the current projects is the Auraki Stream road retreat, which involves the relocation of the highway away from the site of the Mangawhero River slip.

Waka Kotahi regional manager of infrastructure delivery Rob Partridge said the project had been progressing well and on Thursday traffic would be moved on to the new road’s southbound lane.

“Now the main earthworks for the road are complete, we can make the switch.”

The new stretch of road is about 400 metres long, about the same as the previous route, and the new lane will be unsealed at this stage.

Road users would need to be aware of the switch and drive safely, he said.

The same traffic management already in place will remain for the new road, with a 30km/h temporary speed limit and stop/go traffic controllers.

“Follow the traffic management and crews in place. They are there for people’s safety,” Partridge said.

Ongoing earthworks, pavement construction, sealing, line marking and barrier installation will continue once traffic is moved to the new route.

Partridge said Waka Kotahi hoped to open both lanes of the new road at night in June and expected to have both lanes sealed for all-day use by July, depending on the weather.

It was hoped all work would be completed in August.

“In the meantime, planting season is coming up and we are working closely with our iwi partners to design and finalise planting plans for the area for long-term restoration,” Partridge said.

The project includes the development of a new wetland area.

“The Auraki Stream project on SH4 Parapara Rd has been essential to ensure the road remains safe for all users, and resilient and is future-proofed.

“SH4 Parapara Rd is a major trade corridor as well as a scenic tourist route.”

Repairs have already been completed at Hapokopoko Curve Rock, Whiskey Corner, South Raupio Retreat, Otoko Pā overslip and north of Kukuta Rd.