Project update

20 December 2022

Kia ora and welcome to the latest newsletter on Te Ahu a Turanga: Manawatū Tararua Highway – the 11.5km route to reconnect the Manawatū, Tararua District, Hawke’s Bay and northern Wairarapa, replacing the closed State Highway 3 Manawatū Gorge route.

The GRS (geo-synthetic reinforced slope) wall in Zone 2 has been completed.

Key construction features appearing on highway site

While the magnitude and complexity of the earthworks and structure builds on Te Ahu a Turanga: Manawatū Tararua Highway is impressive, a huge amount of less visible but equally important work needs to occur across the site to ensure the success of the project.

A total of 4.5M cubic metres of earth has been moved since construction started in January 2021, which accounts for more than two thirds of the project’s total earthworks of 6M cubic metres.

With much of this progress made during the 2021/22 summer season, the project is now in a good position to complete bulk earthworks in the 2022/23 season.

To enable this level of progress, many other enabling works have to occur, such as establishing erosion and sediment controls, wildlife surveys, waterway defishing, stream diversions, major cross culvert installations, and wind turbine cable relocations.

One interesting feature is the recently completed GRS (geo-synthetic reinforced slope) wall in Zone 2. The construction of the wall involved placing sheets of strong plastic material, called geo-grid, between layers of earth, which enables a very steep wall to remain strong.

With an angle of 52 degrees, building such a steep wall reduces the amount of protected QEII land impacted by the highway. To help the wall blend in with the natural environment, the team placed dense bags of topsoil behind the face of the wall so native plants can grow there. These will be planted during the next landscaping season starting in April 2023.

The longest culvert onsite, a 1650mm diameter, 160-metre-long concrete pipe, known as Culvert 15, has recently been completed. This pipe provides water passage in one of the gullies near the Woodville end of the project.

Work is also under way to prepare for the construction of the roundabouts at both the western and eastern ends of the new road.

At the Ashhurst end, this involves earthworks for the western roundabout and the local road that will connect to the new Te Āpiti – Manawatū Gorge carpark. At the Woodville end, enabling works, including installation of drainage, creation of haul roads, cable relocations and stream diversions, are taking place to prepare for the construction of the eastern roundabout.

Our landscaping teams have finished their second planting season, achieving nearly 500,000 plants in the ground. During the offseason, they switch to maintenance and pest control to protect and support the more than 737,000 plants now growing across the five planting sites throughout the region. Planting along the highway itself will start in the 2022/23 season.

To view the latest flyover footage, please head to the project page on the Waka Kotahi website: www.nzta.govt.nz/projects/te-ahu-a-turanga/

Pictured below is Culvert 15, which is the strip of earthworks in the centre of the picture leading out towards the Saddle Road in the top right.

Pier 1 on Parahaki Bridge has had its column work completed.

Major milestones reached for project's bridges

Some significant milestones have been reached on the six structures across the site.

The first pier of Parahaki Bridge, across the Manawatū River, is now completed. This pier features the first example of mahi toi on the highway, which is a design created by local iwi artist James Molnar. Work is well under way on the two remaining piers.

The form traveller, which is a system that assists in the creation of this balanced cantilever bridge, is being pre-assembled and will be attached to pier 1 in 2023.

The construction of Parahaki Bridge is highly complex, and the team has faced engineering and environmental challenges. The site is located on a faultline, experiences high winds and is impacted by wet weather events.

Across the river at the Eco Viaduct site, 11 of the 12 columns are completed and can be seen from the temporary Te Āpiti – Manawatū Gorge carpark.

The final column is expected to be finished in January 2023, which is fantastic progress considering the issues with artesian groundwater experienced at this site.

The project's three underpasses, Bridge 1, 5 and 10 are all now structurally complete, with Bridge 5 having its concrete roof poured in December. The Mangamanaia Bridge at the Woodville end will start construction in 2023.

Below: Eleven of the 12 columns on the Eco-Viaduct have been completed.

Pupils and staff from Mana Tamariki joined Te Ahu a Turanga Alliance staff on a trip to "The Rock", a wāhi tapu site located near the project site.

Māori immersion school pupils visit Te Ahu a Turanga

A group of kura kaupapa Māori children were delighted to visit the Te Ahu a Turanga: Manawatū Tararua Highway site in September.

The children, from Mana Tamariki in Palmerston North, were visiting the site as part of their learning about Tāwhirimātea, the Māori god of the winds.

The children visited in two groups, with the Year 1 and 2 students coming on 28 September, and the Years 3 and 5 group visiting the next day.

They were welcomed by the Alliance whānau, before sharing kai and getting set up with safety gear. The children were very excited to wear the hard hats, high-vis vests and safety glasses required for visiting a construction site.

Te Putahi members then took the children up to Te Ahu a Turanga (The Mound of Turanga), the peak above Te Āpiti, and the wāhi tapu rock that stands there. They also visited the waharoa at the entrance to the Manawatū Gorge, where they also saw the progress on Parahaki Bridge.

As Mana Tamariki is a full immersion school where staff and students speak exclusively in Te Reo Māori, and at least one parent is expected to speak it at home, the pupils ability to engage with non Te Reo Māori speaking staff on field trips can be limited.

One of the most significant aspects of this visit for the school was being able to come to a site like Te Ahu a Turanga where Te Reo Māori is spoken, and where Te Ao Māori is widely observed.

Plans are in place to bring the high school (wharekura) students in to visit the project in 2023.

Concrete Construction apprentices Phil Seabrook, Sebastian Lomax-Jackson, Jarome Beazley-Waara, Mike Seabrook and Antonio Calachan at the Bridge 5 underpass in Zone 3.

Five structures apprentices gain BCITO qualification

Five apprentices have achieved a BCITO qualification while completing three minor structures on Te Ahu a Turanga: Manawatū Tararua Highway.

The apprentices, Mike Seabrook, of Feilding; Phil Seabrook, of Feilding; Sebastian Lomax-Jackson, of Foxton; Antonio Calachan, of Ashhurst; and Jarome Beazley-Waara, of Palmerston North, used knowledge gained throughout their years in the industry to achieve their National Certificate in Concrete Construction in just over 12 months.

This was an impressive achievement considering it is usually a three-year apprenticeship, and it stands as a good example of the Te Ahu a Turanga project's commitment to providing learning and training opportunities that benefit the community and the construction industry.

All five have been on the project since May 2021. Phil Seabrook has been based at Parahaki Bridge (Bridge 2), while Mike, Sebastian, Antonio and Jarome have been working with supervisor Gareth Thompson on bridges 1, 5 and 10, which are all underpasses providing access underneath the highway for affected landowners.

The team were encouraged to study during work time if there were any down days or periods of time where it wasn’t possible to work on site.

Landslide damage to eastbound shoulder near Kerry’s Wall (view eastbound, toward Woodville) in May 2021.

Future of Te Āpiti - Manawatū Gorge old road

With summer here and a break from work on the horizon for many, getting out walking and cycling will be on the mind.

In Manawatū-Whanganui we’re lucky to have Te Āpiti - Manawatū Gorge at the doorstep, where you can walk or cycle through unique landscape with ancient bush and native birds and plants.

Waka Kotahi NZ Transport Agency is aware of how eager people are to use the old road through Te Āpiti Manawatū Gorge, however it’s still not safe to do so.

In May this year Waka Kotahi announced the draft results of the new geotechnical assessment of the old road through the Gorge.

Work is now progressing investigating the future of the old road. A business case is being developed to consider revocation options for the stretches at each end of the old road still safe for vehicles.

For the rest of the route, with community partners and key stakeholders, Waka Kotahi will come up with recommendations for Toitū Te Whenua Land Information New Zealand to consider.

Find out more at: https://nzta.govt.nz/projects/te-apiti-manawatu-gorge-old-road/

Thank you for your support

Your ongoing interest in the progress of Te Ahu a Turanga: Manawatū Tararua Highway is very much appreciated. This will be the final update for the year, so on behalf of the Te Ahu a Turanga team, I'd like to thank you for your support and wish you all a happy and safe festive season. We'll be back in early 2023 with more stories, updates and pictures about the project.  

Ngā mihi nui

Jonathon Howe
Communications and Stakeholder Engagement Manager

More information

For more information on the Te Ahu a Turanga: Manawatū Tararua Highway, please use one or more of the following methods:

• Website: www.nzta.govt.nz/teahuaturanga
• Facebook: facebook.com/nztacni
• Twitter: twitter.com/WakaKotahiCNI
• Email: teahuaturanga@nzta.govt.nz
• Phone: 0800 740 560