A look at a completed section of the road approximately three kilometres from the Ashhurst end of the new highway.

Te Ahu a Turanga: Manawatū Tararua Highway opened to traffic on 11 June after the official blessing and opening on 7 June.

The new road, its many feats of engineering and the unique partnership that built it were celebrated.

Construction began in January 2021 on the $824M project (including client costs) to build a new route over the Ruahine Ranges after a major slip in April 2017 left SH3 through the Manawatū Gorge impassable.

Chief Operating Officer NZ Construction, Justin McDowell, says it’s hard to under-estimate the scale of the project.

“The more than six and a half million cubic metres of earthworks is the largest of any project I’ve been involved in, and it needed to be done around wind turbines and in widely varying soil types,” says Justin.

“It was a real feat of engineering as the team worked out how to cut the profile around the wind turbines and they did a great job.”

Justin says another ingenious aspect was Bridge Two, as it’s a cantilever bridge that is curved and used rockers – a first for New Zealand – that allowed the structure to rock safely during the event of an earthquakes under construction.

He reserves his biggest accolade for the team.

“It was a long project in a testing physical environment and I’m in awe of Tony (Adams) and his team for their application to the task and management of the relationships that are central to an alliance project. I suspect, for many, it will be a career highlight project.”

Project Director, Tony Adams and the project team celebrate the completed Parahaki Bridge in late 2024.

A project highlight and engineering marvel are the 300m-long Parahaki Bridge and neighbouring steel girder 12 column Eco Viaduct.

These two large and complex structures were built over a river, an ecologically sensitive wetland and a fault line in an area with challenging ground conditions and strong winds.

The Parahaki Bridge with the Eco-Viaduct just to the north under construction.

Fulton Hogan is proud to be a part of the Te Ahu a Turanga: Manawatū Tararua Highway alliance with NZ Transport Agency – Waka Kotahi, HEB Construction, Aurecon, WSP, Rangitāne o Manawatū, Rangitāne o Tamaki nui-a-Rua, Ngāti Kahungunu ki Tāmaki nui-a-Rua, Ngāti Raukawa ki te Tonga and Nga Kaitiaki ō Ngāti Kauwhata.

Key features of the project include:

• 11.5km of new four-lane highway between Ashhurst and Woodville.
• More than six and a half million cubic metres of earthworks.
• Six structures, including two bridges of more than 300m long.
• Cuts of up to 55m in depth.
• Embankments up to 28m high.
• Roundabouts at the eastern and western entrances.
• A shared use path for pedestrians and cyclists.