Kia ora and welcome to an update from the Transmission Gully team.

Kia ora

Kia ora and welcome to an update from the Transmission Gully team.

Like you, we’re very keen to see the new motorway open to the public as soon as possible and want to assure you that our project team is working as hard as possible, within the necessary health and safety protocols. 

We know that many of you are frustrated about the delays – and we appreciate your patience for just a while longer. You'll see from the latest images that the project team is making great progress. However there are other critical requirements including safety and asset quality assurance work and compliance with environmental consent conditions, which need to be met before the motorway can legally be opened for public use. 

I can tell you that it will be worth the wait – the new motorway is a spectacular piece of new infrastructure that will deliver increased safety for motorists and a major step up in resilience for the region.

The complexity and scale of the construction task that has been achieved is evident in the imagery provided in these newsletters and on the project website. I encourage you to check out the website content designed to familiarise motorists with the route including the four new interchanges  - so that when you do (finally) get to drive the Transmission Gully motorway you'll be well prepared!

Sergio Mejia

Chief Executive, Wellington Gateway Partnership

Transmission Gully project website

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Construction update

Work continues at pace on the project, despite the challenges caused by Covid restrictions.

In October we finished nearly all of the asphalt surfacing in the southern section of the project. This means all surfacing from SH58 to SH1 Linden is now complete except for a short stretch on the existing SH1 at Linden. This will be done over two weekends (Friday night/Saturday morning) from 5/6 November.

One of the biggest recent achievements was the installation of two cross-motorway gantries on the existing SH1 at Linden and Mackays Crossing.

The gantries use steel trusses to span the width of the motorway.  The gantries will hold green directional (guidance) signs, (electronic) variable message signs and other Intelligent Traffic System devices.

The gantry installation work involved full overnight closures of SH1 at Linden and Mackays Crossing and required the use of a crane to lift the 34 metre long, 30 tonne gantries into place.

The first two nights of work at Linden were postponed due to high winds (making it unsafe for the cranes), but in the end the team succeeded in getting the entire gantry fully erected in just one night, rather than the three they’d planned for.

Watch some of the team at work

The Kenepuru interchange and southern end of Transmission Gully.

New motorway sign gantries have been installed at Linden.

It was all hands (and cranes) on deck to get the job done.

Happiness is – a successful gantry installation.

At Mackays Crossing, the job was also completed in just one night – rather than three. A terrific effort, and great news for SH1 travellers too.

Because the directional signage includes reference to the renumbered section of SH1 (Linden – Mackays) as SH59, the signs will be installed on the gantries closer to the renumbering taking effect.

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The Radar system on Transmission Gully

The Transmission Gully motorway has been built to the highest safety specifications, and one of the key ways the motorway will keep people safe is through its radar system. The radar units will detect incidents and be monitored by an operations team who will send assistance as required.

Known as an Intelligent Transport System (ITS), radars of this type are widely used in Europe – but are new here. Designer and ITS co-ordinator Jeff Greenough says; “It’s the first extensive radar system to be used to monitor a motorway in New Zealand.”

The radar units monitor traffic movements and can identify if a vehicle has stopped on the road or is going the wrong way. It’ll also pick up pedestrians walking on or next to the motorway, any stray animals wandering around, or debris, such as boxes that have fallen off the back of a truck.

Radar units are positioned along the whole length of the Transmission Gully motorway.

“Each radar has a 500-metre radius, so there is no portion of the motorway that won’t be seen”, Jeff says.

The radar system will be monitored 24/7. That’s eyeballs on screens all day and all night in a traffic operation centre. Jeff says think of it a bit like air traffic control; “The vehicle or object appears on the screen as a moving (or static) dot. Operators can tell what direction it’s moving in or whether it’s moving at all.”

A goat …a pedestrian ...things dropping off a vehicle …anything travelling at a speed below a set threshold will trigger an alarm in the operations centre. Pan, tilt and zoom cameras are located at key spots along the motorway. Operators can instruct the camera to swivel around to where the alarm has been triggered to help them gain more information about what is going on.

It means that crashes or an incident will be detected immediately – and can be quickly responded to by an Incident Response Team, and Emergency Services if required.

Ventia is the company that Wellington Gateway Partnership has subcontracted to operate and maintain the motorway for the next 25 years. It’s the Ventia team who are in charge of responding to incidents picked up by the radar system, which might involve sending out a vehicle to assist.

Ventia’s Aaron Lacey says there are different response strategies for different needs.  “If a vehicle has a puncture, only one Incident Response Vehicle (IRV) may be needed to help get the motorists mobile again. If there’s a more serious incident, the response team will co-ordinate with Emergency Services,” he says.

While it’s expected crashes will be rare due to the design of the road, if there is a crash, emergency services will be supported at the scene by Ventia’s incident response team. Traffic management vehicles may also be dispatched to close a lane or clear the road of debris.

The Incident Response Vehicle is fitted with equipment to support safety such as basic firefighting and first aid equipment including a defibrillator. It also contains gear to clean the immediate area and to maintain safe vehicle movement through the area.   

The Ventia response team can do everything from calling a tow truck for you to putting a bit more fuel in your car. “We don’t want stopped vehicles creating safety issues on the road, wherever possible we want to keep people moving,” says Aaron.

The radar system will be a new and positive change for New Zealand motorists.

While a company in the UK has designed the radar system, it has undergone extensive testing on site to ensure it’s ready for the New Zealand environment and the Transmission Gully terrain.

Every 100 metres of the motorway in both directions is considered a ‘section’ and is tested. That’s 280 sections northbound… and another 280 sections southbound, plus all the on and off ramps and interchanges.

The tests have involved doing fun but important things like the ITS team throwing boxes off the back of a ute, stopping a vehicle and getting out and walking along the shoulder, or driving very slowly or even in the wrong direction.

It’s all about ensuring the radar system is working effectively from the first day public traffic is on the road.

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Emergency services

The project team is working closely with emergency services ahead of opening, to ensure that all services are familiar with the route and the terrain.

Recently, Fire and Emergency NZ (FENZ) personnel came out to site for a familiarisation tour.

There were two separate tours to accommodate the number of crews. The fire crews made stops along the motorway at some of the most significant locations along the route.

Fire trucks on Te Ara a Toa, the bridge over Cannons Creek.


A total of 76 FENZ personnel attended with approximately 20 fire trucks.

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Mobile phone coverage

As with many roads through rural areas, there are sections of the new motorway without mobile phone coverage. These areas vary by mobile network provider.  In an emergency, 111 calls will automatically divert to any available mobile network.

Where motorists are unable to obtain a cellular connection they must remain in their vehicle.  

In the event of a breakdown or emergency you’ll be detected by the radar system and the incident response team will be on their way. Ventia has full radio coverage along the entire length of the motorway.

There are tips for driving on Transmission Gully, including what to do in an emergency on our website.

Tips for driving on the new motorway

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How to use the Waitangirua Interchange

Want to see how Eastern Porirua and Whitby locals can use Transmission Gully to travel?

Just before the August lockdown, the Transmission Gully team invited Whitby and Waitangirua locals Sheryn and David to try out the new motorway from the Waitangirua Interchange. See what their new journey will look like along Transmission Gully and the new connecting Porirua link roads!

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Mobile Visitor Centre

The Transmission Gully Mobile Visitor Centre has had a makeover! We have updated information about how to use the motorway including large maps of each interchange to help you plan your journey.

The Visitor Centre is currently located in the Coastlands carpark in Parapapaumu. It’s situated at the old SH1 entrance, opposite Countdown and next to the train underpass.

The Visitor Centre now has detailed maps and information about how to use the interchanges.

Artist Anthony June, who created the original artwork on the outside of the container, has returned to add to his mural, spraying; ‘Transmission Gully’ across the back of the container, making it easy to spot from the road.

Visitor centre artwork by Antz (Find him on Facebook under ANTIS_Graphicz).

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Shot bro

The TG workforce were offered Covid vaccinations on site earlier this month. Thanks to the Coastlands Mobile Vaccination team and the Hutt Valley and Capital and Coast District Health Boards.

In total 75 workers took up the opportunity and were treated to a muffin and a cold drink with their jab. It was the first shot for half the group, so the Vaccination team will be back in six weeks to give the second dose.

Abseiling specialists Luke Cunningham and Steven Turner meet with the Vaccination team.

Access Rope technician Steven Turner gets the jab.

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Keeping in touch

If you have any questions, please contact us at info@tg.co.nz. If you have an urgent matter, please call the 24-hour project hotline on 0800 TGINFO. If we are working outside of our normal work hours and you’re one of our neighbours, we’ll be in touch with you directly as usual.

But for now, Haere rā from the Transmission Gully team.

Carpenter, Ephraim Anselmo getting vaccinated against Covid 19.

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