Wellington Scoop

NZTA promises Transmission Gully will be open next September

t gully steep incline
RNZ photo

Report from RNZ
The New Zealand Transport Agency today issued a promise: Wellington’s Transmission Gully will be open for motorists next September.

It came as reporters were taken on a behind-the-scenes tour of the 27km highway, which has been beset by delays.

The new arterial route was supposed to cost $850 million but the budget has blown out – now costing $1.25 billion, and there have been delays.

The Wellington Gateway Partnership is responsible for the financing, design and construction of Transmission Gully and its operation and maintenance for the next 25 years, and chief executive Sergio Mejia said that without Covid-19, the road would already be in use.

He said the project was on track to be open by September, and there were very few things that would stand in its way.

“Inclement weather, seismic events. It’s pretty much what affects rolling projects like this.

“I am certain we are going to hit target. We are fully committed and we are on schedule.”

He cited the pandemic as the major reason the April 2020 date was not met.

Constructing Transmission Gully has meant 25 bridges or culverts had to be built to carry motorists from the Kāpiti Coast into Wellington. The largest is Te Ara o Toa – or bridge 20 – which stretches more than 200m over Cannons Creek.

On the Wainui saddle, the sheer scale of the project becomes clear. Hillsides have been gouged out and a stream moved 30m to allow the highway to take shape, with giant earth walls up to 95m deep. The terrain is also earthquake prone and mostly farmland, meaning culverts had to be dug under roads to allow farmers access to their land.

NZTA senior manager Andy Thackwray said the project was one of the country’s most complex yet.

“It’s the most challenging, the most complex and, yes, most expensive project. We have had the Kaikōura earthquake, adverse weather and the pandemic to contend with.”

He said he was confident the project would hit its September opening date. With the project now 85 percent complete, Mejia says it was nice to think the end was in sight. “I can see the light at the end of the tunnel. I can’t wait until September 2021.”


  1. Chris Horne, 25. November 2020, 12:24

    The image featuring giant bandages covering Wainui Saddle’s steep slopes fills me with awe and apprehension. In 2014 I tramped from Battle Hill Farm Forest Park along the Transmission Gully route up the valley of Horokiri Stream to the saddle, then down the valley of Te Puka Stream to the present SH1. The bandages hide evidence of the since-felled magnificent kohekohe/nikau forest which then clad the steep slopes west of and above the saddle and Te Puka valley. Woe betide the fate of the earthworks and their bandages when heavy rain, such as we have today, combines with movement of the Owhariu Fault which crosses the saddle. Surely they will all come a-tumbling down!

  2. Dave B, 25. November 2020, 13:30

    Hardly the route to de-carbonization which we are told the planet so urgently needs. This will keep us all trucking and vrooming like nothing else matters. We could have eliminated the North-South Junction railway-bottleneck for a fraction of the cost of this.