Northland Corridor

27 February 2025

Project update - February 2025

Tēnā koe and welcome to the Northland Corridor newsletter.

Our final 2 events for the Summer Roadshow took us to the Waipu Street Market and the Paparoa A&P Show.  Thanks to everyone that has visited us across all the Summer Roadshow locations.  We spoke with over 1,500 people across the 7 events and had some great conversations. We appreciate all the local insights we received and have passed this onto the wider project team.  It was clear that most of you just want us to ‘get on and build it’! 

With investigation work on Ara Tūhono – Warkworth to Te Hana making good progress, we are holding community information sessions in Warkworth and Wellsford.  Check out the details below to find out where we’ll be. 

In this edition of the newsletter, we have photos and a video showing the progress we are making with geotechnical investigations on Ara Tūhono – Warkworth to Te Hana and an update on Te Hana to Port Marsden Highway and Port Marsden Highway to Whangārei.

Community information sessions Ara Tūhono – Warkworth to Te Hana

We had such a great response to our Summer Roadshow that we’re holding 2 more information sessions in Warkworth and Wellsford. We’ll be sharing the progress we’re making on Ara Tūhono – Warkworth to Te Hana, 1 of the 3 new Roads of National Significance that make up the 100km corridor between Warkworth to Whangārei.

We’ll be at Warkworth Masonic Hall on Saturday 1 March from 10am – 2pm and Wellsford Community Centre on Saturday 8 March from 10am – 2pm. Join us for a chat.  We hope to see you there!

The geotechnical team on location in the Dome Valley. Ara Tūhono – Warkworth to Te Hana alignment will run through the valley in the background. The team are collecting core samples, this example is of sandstone.

Section 1 update: Ara Tūhono – Warkworth to Te Hana

Our geotechnical team are making huge progress with 97 boreholes now drilled.  The team have been in remote forest locations in the Dome Valley, drilling to depths of 180m to gather core samples for the proposed twin tunnels included in the indicative design.

The proposed tunnel alignment traverses the Dome Valley in a northwest direction with depths reaching 130m below ground level. The alignment will then travel through the valley visible in the background of the photo beyond the trees. 

Core samples collected are taken back to the lab for testing to determine the level of moisture, and composition and strength of the material.  This helps the team understand how the material will act when the excavation for the tunnels occurs. 

The information collected from these core samples is interpreted and collated with samples from over 100 different drilling sites.  This provides a comprehensive picture of the ground conditions along the alignment.

Some drilling sites, like the one above, are located in thick pine forest in the Dome Valley. We use helicopters to transport the drilling rigs, part by part, to access the required location and to reduce disturbance to the surrounding area.   This video shows the action out in the field.  In the next newsletter we’ll have more footage including interviews with our staff on the ground.

Section 2 & 3 update: Te Hana to Whangārei

We continue to work at pace on Te Hana to Port Marsden Highway (Section 2) and Port Marsden Highway to Whangārei (Section 3) and will make decisions about the emerging preferred corridor study area by the end of the first quarter 2025.

We have many workstreams pulling together to consider the previous work done in the corridor area and are reviewing it in line with the Roads of National Significance design standards, along with local insights we have heard from the community and stakeholders. This information will help us in the first steps of knowing where the general corridor will go. When we come back to the community once we’ve made decisions about the corridor, we will share whether each section will be located west, centrally or east of the existing SH1.

Although we are looking at the corridor as a whole, we have split sections 2 and 3 into smaller areas to make the process easier.  Sections 2 and 3 make up approximately 75km of the full 100km Northland Corridor and there are different challenges in each sub-section that need to be considered. Some of the things the team are considering when developing this emerging preferred corridor study area are cultural and archaeological sites, Costal Marine Areas (CMAs), flood prone areas, ground and soil conditions, areas of Outstanding Natural Landscapes (ONL) and access to the current SH1 to name a few. These factors all feed into the level of complexity to eventually build the road and will impact the cost and ease of constructability.

Alongside this work we are partnering with iwi and hapu seeking their valuable input on our plans to date. We also continue to work closely with other entities and key stakeholders including local councils to align our planning with the work they are doing in parallel across the corridor area.

Meet the team

Meet Chad Brown, he operates 1 of the 3 new helicopter portable drilling rigs (seen being transported in the above video) for the Ara Tūhono – Warkworth to Te Hana project.

Tell us about yourself and your role

At a young age I watched both my father and grandfather work in the drilling industry. Following in their footsteps I've worked in the drilling industry for 30 years, working on many major roading and infrastructure projects over my career.  The most notable is working on the ground investigation drilling for the expansion of the northern motorway back when it used to finish in Albany.

As a driller on the Ara Tūhono – Warkworth to Te Hana project, my job is not only drilling but sharing my experience and knowledge with my colleagues to get the best possible result for the project.

What excites you about the Ara Tūhono – Warkworth to Te Hana project

On this section of the project the terrain through the forestry block is challenging and gaining access to investigation locations is not always possible by road. Being in the bush and flying rigs into sites makes for some exciting work, nice scenery, and something a little different from the normal.

It's a great place to work with a great team of very talented people and as part of the ground investigation team we often don't see these projects again until they’re finished. The engineers and designers have done a fantastic job on Ara Tūhono – Pūhoi to Warkworth and I can’t wait to see this road extend and connect to Whangārei.

More information

For more information on the Northland Corridor project, please visit Northland Corridor | NZ Transport Agency Waka Kotahi or contact us at northlandproject@nzta.govt.nz