Te Oreore Slip on State Highway 4

Te Oreore Slip on State Highway 4

When a major slip event occurred at Te Oreore in October 2019, it disrupted the lives of many local families and businesses who use State Highway 4 between Raetihi and Whanganui.

The slip affected State Highway 4 as well as surrounding land owned by Ātihau-Whanganui Incorporation located 18 kilometres south of Raetihi, and it was important for both the Incorporation and Waka Kotahi NZ Transport Agency (NZTA) that this vital link was reconnected. The solution was for a temporary road to be established as soon as possible with a permanent and more resilient road built in the future.

The Incorporation played a vital role in assisting Waka Kotahi to design and build the two-lane, sealed temporary road, which opened just before Christmas 2019.

Whetu Moataane, Tikanga and Branding Manager at ĀtihauWhanganui Inc, was pleased with the response and care taken by Waka Kotahi and its contractors.

“It means a lot for Ātihau, our whānau and community to have this temporary road. People were anxious because this road is the only reliable access they have to their homes and farms,” says Whetu.

“We applaud NZTA, Higgins Construction and their crew, who did such a great job to complete this road in only three months, and just before Christmas too.”

AWHI Tikanga & Brand Manager, Whetu Moataane.

All images supplied by Waka Kotahi NZ Transport Agency.

State Highway 4 is an important link to Raetihi, emergency services, forestry, agriculture and the broader community to Whanganui. While it was damaged, the detourvia Fields Track addedat least 30 minutes, or much longer using other state highways, to the trip between Raetihi and Whanganui.

NZTA Regional Transport Systems Manager (Manawatu, Whanganui and Taranaki) Ross I’Anson is grateful to the guidance provided by Ātihau-Whanganui Inc.

“They welcomed us into the area and opened the door to some good conversations,” says Ross. “When the slip happened, we worked closely with the Incorporation and Ngāti Rangi right through to when the work started. We were cognisant of wāhi tapu sites and worked closely with them to identify these and any other areas of cultural significance.”

The blessing led by Ngāti Rangi iwi, staff of Ātihau-Whanganui Inc, NZTA and Higgins Construction.

Ross also notes how accommodating Ātihau-Whanganui Inc were in providing access to the site prior to the beginning of construction.

“We’re grateful to the organisation which arranged for fences and stock to be moved to enable safe access to the area for our contractors. This included entry for monitoring purposes and then the eventual moving of earth, drainage, putting in culverts and then the building of the temporary road.”

Before construction began on the temporary road there was a blessing by Ngāti Rangi to acknowledge the whenua and also ensure the safety of those working on site, and a special opening and blessing by Ngāti Rangi members and representatives from Ātihau-Whanganui Inc, NZTA, contractors and local officials was held when the road was completed.

“It was great to open this road in such a short space of time,” says Ross. “Locals turned out in their droves which demonstrated the importance of re-opening this link to the community.

Left to right: Elijah Pue, Raana Mareikura, Harete Hipango (MP for Whanganui) and Vera Whakaaronui Wilson.

The slip happened in a region where hillslopes are steep, and the underlying rocks are weak. This makes the area susceptible to landslips as a result of events such as earthquakes and prolonged periods of heavy rainfall.

Remnants of the old road remain down the hillside towards the Mangawhero River, but the temporary road has been built over the slip, which was 30 to 50 metres deep.

The slip area continues to be monitored. To help stabilise the ground, poplar tree poles have been planted with the aim of preventing further slips, as each plant takes about 100 litres of water a day from the ground.

Work toward strengthening the relationship between Waka Kotahi and Ātihau-Whanganui Inc continues to grow in strength, as a solution for the permanent road is implemented.

“The NZTA are engaging with us, Ngāti Rangi and local hapū Ngāi Tuhiariki as building a permanent solution is still a matter of urgency,” says Whetu.