Frequently Asked Questions

Project Overview

What is the Pūhoi to Warkworth Project?

The new Pūhoi to Warkworth project will extend the four-lane Northern Motorway (SH1) 18.5km from the Johnstone’s Hill Tunnels to just north of Warkworth. It is the first stage of the Ara Tūhono – Pūhoi to Wellsford Road of National Significance.

Ara Tūhono means a connecting pathway (Ara meaning pathway/passage and Ara Tūhono means connecting or linking one part to another).

The highway will be built to the west of the existing SH1 and bypass Warkworth on the western side. It will be a four-lane dual carriageway, separated by a central median with a safety barrier.

The Pūhoi to Warkworth project is a PPP (Private Public Partnership) between the Government and a private consortium, the Northern Express Group (NX2). It will be open for traffic by late 2021.

While the NX2 private-sector consortium will be responsible for financing, designing, building, maintaining and operating the motorway for up to 25 years, the motorway will remain a public asset.

Why do we need a new motorway

Traffic modelling from 2012 shows an average 19,700 vehicles travel SH1 per day between Pūhoi and Warkworth. Modelling estimates for 2026 show 31,300 vehicles per day using both the new RoNS and the former SH1.

Several fatal crashes have occurred between Pūhoi and Warkworth in recent years, some of which were head-on collisions. A divided motorway with a central median barrier and improved road design will greatly improve safety.

What benefits will the motorway provide?

It will provide more reliable travel times, a better freight connection for Northland to the Upper North Island freight “Golden Triangle” (Auckland, Waikato and Tauranga) and support economic and population growth.

Time savings are expected to be greater for freight due to reductions in grades and a better road layout, which helps heavy vehicles maintain a higher average speed along the route.
It will also enhance inter-regional and national economic growth and productivity; improve connectivity between the growth areas in the northern Rodney area; and improve the reliability of the transport network through a more robust and safer road between Auckland and Northland.

Other benefits include alleviating congestion at Warkworth by providing a bypass for through traffic, while increasing travel time consistency. The forecast for 2026 for the afternoon peak period traffic shows an approximate 7-minute time saving for a motorist travelling north from Pūhoi to north of Warkworth.

The 2026 forecast for a motorist travelling south from north of Warkworth to Pūhoi shows an approximate 16-minute time saving.

What benefits will there be for the economy of Northland?

Connecting Northland is about ‘providing land transport solutions that enable territories of Northland and Northland as a region to improve and grow economic and social opportunities in a manner that brings central and local government together so they can act individually and collaboratively, turning opportunities into realities.’

Through greater highway solutions, design, delivery and management, the State Highway network will bring greater investor opportunity and productivity, mitigating unreliable and costly journeys between Northland and key markets. Key goals are:

  • Creating safe, reliable transport links that foster the economy and improve the quality of life for its residents is one of the keys to unlocking Northland’s economy.
  • A resilient, reliable transport network will enable Northland to become a significant contributor to the nation’s GDP, alongside Auckland, Hamilton and Tauranga, also known as the ‘golden triangle’.
  • Tourism and primary production are the key drivers of the Northland economy and rely heavily on transport.
  • Protecting and improving the freight link between Auckland and Northland is essential to sustaining and growing the Northland economy.

This allies with the Tai Tokerau Northland Economic Action Plan launched in February 2016. The plan is now being implemented by regional bodies, central government agencies, industry groups, and local businesses and iwi, with a focus on business growth by prioritising infrastructure improvements relating to transport, digital infrastructure, skills and capability, and water.

What is the significance of the Te Reo name?

Ara Tūhono means a connecting pathway (Ara meaning pathway/passage and Ara Tūhono means connecting or linking one part to another).

What are RoNS?

The Roads of National Significance (RoNS) programme is a key part of the Government’s National Infrastructure Plan and its investment priorities as outlined in the National Land Transport Programme (NLTP).

The seven RoNS projects are based around New Zealand’s five largest population centres: Auckland, Hamilton, Tauranga, Wellington and Christchurch. Other RoNS may be added in future but from north to south the seven projects either completed or underway are:

  • Ara Tūhono – Pūhoi to Wellsford – State Highway 1
  • Western Ring Route, Auckland – State Highways 16, 18 and 20
  • Victoria Park Tunnel, Auckland – State Highway 1 (COMPLETED)
  • Waikato Expressway – State Highway 1
  • Tauranga Eastern Link – State Highway 2
  • Wellington Northern Corridor – State Highway 1
  • Christchurch Motorways.

The focus is on moving people and freight between and within these centres more safely and efficiently. The RoNS are ‘lead infrastructure’ projects – that is, they enable economic growth rather than simply responding to it.

All seven RoNS have been identified through regional land use and transport studies as being strategically-significant investments. Identifying and labelling these corridors as RoNS signalled their importance, priority and certainty.

What is the final contract price?

The net present cost for delivering the motorway through a PPP is $709.5 million.

Will Pūhoi to Warkworth be tolled?

No decision has been made on tolling for the Pūhoi to Warkworth motorway. The public would be fully consulted on any tolling proposal which must also obtain Ministerial approval. Should the motorway be tolled, the Transport Agency would retain responsibility for tolling (not the PPP Contractor).

Project Partnership

What is the involvement of local iwi?

Hōkai Nuku is a Transport Agency treaty partner. Hōkai Nuku is an alliance formed by the mana whenua of the area to provide advice to the Transport Agency on the wider Ara Tūhono project.

Hōkai Nuku comprises representatives of Ngāti Manuhiri, Ngāti Mauku/Ngāti Kauwae/Te Uri o Hau of Ngāti Whatua, Ngāti Rango and Ngāti Whātua iwi.

The Northern Express Group (NX2) is working on a Hōkai Nuku Partnership Plan which outlines NX2’s strategy for working collaboratively, encouraging communications and building and maintaining effective relationships with Hōkai Nuku.

How are stakeholder interests being protected?

NX2 is committed to engaging with stakeholders on all of its projects and that commitment will not change under a PPP.

The PPP contract stipulates the required engagement for the PPP contractor to undertake, and NX2 has committed to ongoing two-way communications with the community including a website, newsletters, information boards and a toll-free number where people can get further information. Other activities will include information days and meetings with community and special-interest groups.

Will the New Zealand public still own the Ara Tūhono – Pūhoi to Warkworth motorway?

While the NX2 private sector consortium will be responsible for financing, designing, building, maintaining and operating the motorway for up to 25 years, the motorway will remain a public asset – it is never owned by the PPP consortium.

What is a PPP?

A Public Private Partnership (PPP) is a long-term contract between the public and private sectors covering the financing, construction and operation of a public infrastructure and services. Full ownership of the public infrastructure remains with the public sector.

Pūhoi to Warkworth will be an ‘availability’ PPP. This means that payments are not linked to traffic volumes. They are made when a safe road is open and is delivering the prescribed outcomes.
The outcomes-based PPP for this project has allowed flexibility to achieve innovative outcomes in design and construction.

The motorway is the second project to be delivered through a PPP in New Zealand, the first being the Transmission Gully project in Wellington which will be open for traffic in 2020.

What are the benefits of a PPP?

They allow large and complex projects to benefit from private sector innovation and funding which can increase certainty of delivery and give better value for money. There are also savings to be had on all aspects of the project – design, build, maintenance and operational management.

Traditionally the New Zealand Transport Agency (NZTA) provides the finance for major roading projects. In this case, NX2 will be responsible for financing, designing, building, maintaining and subsequently operating the motorway for up to 25 years.

However the motorway will remain a public asset – it is never owned by the PPP consortium.

Who are the partners in the Pūhoi to Warkworth PPP?

The Transport Agency and the Northern Express Group (NX2).

The Transport Agency represents the public sector and is involved as a procurer and regulator of the highway rather than being a direct provider of the contract for outcomes to the public.

The Transport Agency will commit to making debt payments for up to 25 years once the motorway is available to traffic and continues to meet the prescribed outcomes. These payments will be made through the National Land Transport Fund.

The private sector (NX2) becomes the long-term financier, designer, builder, manager and maintainer of the highway rather than just being the builder of that highway.

NX2 is made up of companies with considerable experience in the design, construction, finance, maintenance and management of key infrastructure projects in New Zealand and overseas. NX2’s equity investors are the Accident Compensation Corporation and Public Infrastructure Partners II LP (managed by Morrison & Co PIP Limited), ACCIONA Concesiones and Fletcher Building.

  • The ACC maintains one of NZ’s largest investment funds in order to cover the full future costs of all accepted claims.
  • H.R.L. Morrison & Co is a specialist investment management firm and an active long term investor in PPPs
    ACCIONA is one of the foremost Spanish business corporations, a leader in the development and management of infrastructure, renewable energy, water and services
  • Fletcher Building Limited is Australasia’s largest building materials manufacturer and distributor and is involved in residential and commercial construction.

Who will complete the management and maintenance contract?

The Asset Management and Maintenance Joint Venture (AMM) sub-contracted by NX2 for these works is between ACCIONA Concesiones and Higgins.

Is there any difference between the PPP model used for the Pūhoi to Warkworth project and that used on PPP highway infrastructure projects overseas?

In the past, many overseas PPP highway infrastructure projects passed patronage risk back to the private sector (i.e. revenue from patronage was used to pay for the private finance). However in recent years, many PPPs in Australia and elsewhere have been constructed using the ‘availability’ model that has been chosen by the Transport Agency for the Transmission Gully project and now for this motorway. This means that the PPP consortium will be paid for making a safe road open and available to traffic.

The key outcomes for the project include delivering a motorway with high and sustained safety standards that will be a high-quality asset for the whole of its life, ensuring predictable journeys for drivers, and maintaining and enhancing the motorway standards set by the Transport Agency. There are incentives for the private sector to achieve quality levels of service through commercially-incentivised performance targets.


Why is the Warkworth access to the north?

To provide better journey time reliability and regional connection, the new motorway bypasses Warkworth township and reconnects with the current SH1 about 2.5km north of Warkworth. This also reflects feedback from the public consultation held by the Transport Agency in 2010 and further technical analysis.

Can’t you use the road over the top of the toll road tunnels as an on-ramp?

The current one-way road connection for southbound traffic travelling to Waiwera and Orewa will be changed to allow for two-way traffic once the new motorway opens. It will join the old SH1 that is superseded by the new motorway.

The current one-way road that carries traffic northbound from Waiwera and goes over the tunnels will be closed to general traffic and access will be restricted to occasional use by maintenance vehicles and emergency services. It will connect to the new motorway but it will not be built to the standards required for use by general traffic.

How will the intersection work at Pūhoi?

At Pūhoi, the ramps on to and off the motorway are both “south-facing”. This means if you are heading north, you can exit at Pūhoi. You can also go south by joining the motorway at Pūhoi. For Pūhoi traffic going north to Warkworth, or for traffic from Warkworth going to Pūhoi, drivers will use the current SH1. Access will be at an intersection reached by a road going underneath the new motorway.

Why are there no north-facing ramps (i.e. northbound on-ramp and southbound off-ramp) planned for Pūhoi?

At this stage, we do not expect enough demand for north-facing ramps for several years and therefore they are not included in the current project. North-facing ramps also present a number of engineering and environmental challenges and would have a significant cost. The current designation has enough space for future ramps should they be required.

What are the safety features of the motorway?

The motorway is designed to international standards to be one of the safest roads in NZ.
A key part of this is the Operating Speed design philosophy which has targeted the safe elimination of large speed differentials along the route. The absence of long straights and wide curves discourages drivers from reaching high speeds even with aggressive driving.

The Operating Speed approach is used extensively overseas and NX2 has tailored the model for New Zealand conditions.

At Moir Hill, to prevent any hold-ups for fast-moving traffic, an extra lane for slow vehicles will be provided to the left of the two normal lanes, allowing for faster traffic to pass (including faster-moving trucks). We will also implement speed-reduction strategies at the northern end of the motorway to control speeds as vehicles head northbound into the slower-speed roads of Warkworth and the wider State Highway network.

The introduction of wire rope barriers to prevent head-on collisions, fully-sealed medians and shoulders, emergency truck stopping areas and rockfall mesh barriers will all help protect road users and maintenance workers who will have minimal need to work in live traffic.

We will apply an open-graded porous asphalt (OGPA) surface to drive on because it offers a number of superior safety and durability features. The surface is porous and is not subject to water spray, flooding and aquaplaning.

All safety measures developed have been assessed against the Transport Agency’s Safer Journeys and Safe System approach.

Developing an integrated design and maintenance solution with a safety-first approach has enabled NX2 to achieve a high rating of 4.8 under KiwiRAP (a road assessment programme in which experts analyse the road safety of the State Highway network).

This positions the motorway as one of the safest roads in New Zealand.

What are the main design features?

People using the road will have a truly scenic trip. Going through the majestic cut slopes of Pakiri sedimentary rock up to 50 metres high will give a sense of penetrating through the rock face. Wire mesh will be laid over the rock face to prevent any rock falls. The steep cuts allow existing vegetation on the top of hills to be retained. The road will be curvilinear (following a curved pathway) without long straights. It will follow the natural contours of the land as much as possible. This will add to the scenic drive with views over the landscape in places and in other sections the road will go through forested areas, rather than being above the tree canopy, and then will wind between steep natural rock faces. Low plantings on the sides of the roads will enhance the scenic view.

The curved road and the flexibility to position the road within the designation (the broad footprint in which the road has to fit) allow us to avoid going through some of the most ecologically-sensitive areas in the district. Lighting will be kept to a minimum to prevent “light pollution” at night, in keeping with a rural landscape. Lighting will only be seen at the Pūhoi and Warkworth intersections and near the Johnstone’s Hill Tunnels.

Who is doing the design and construction works?

The Construction Joint Venture (CJV) sub-contracted by NX2 for these works is between ACCIONA Infrastructure and Fletcher Construction. In turn, the CJV is subcontracting design work to Beca and Tonkin & Taylor among others.

What is Greenroads?

Greenroads is an international sustainability certification system that is specific to the design and construction of roading projects. Greenroads certification applies to specific projects and certification is sought by project teams during detailed design and construction.

It requires the achievement of 12 mandatory project requirements. Points can then be earned from over 40 voluntary credits delivering sustainable outcomes such as habitat conservation, work zone health and safety, and recycled and recovered content.

If more than 40 points are achieved the project is certified as a Greenroad.

Project teams progressively upload evidence to show they have achieved project requirements and credits during the detailed design and construction phase.

Certification normally occurs after the project opens. Four certification awards are available depending on the number of points achieved.

NX2 will achieve a Greenroads® Silver Rating for the Pūhoi to Warkworth motorway, the standard set by the NZ Transport Agency.

What will happen regarding the next stage of Ara Tūhono – the section from Warkworth to Wellsford?

The Transport Agency is planning to release an indicative route for the Warkworth to Wellsford section in early 2017.

Route protection for future construction is subject to regulatory processes and the Transport Agency is working towards designating the Warkworth to Wellsford section by the end of 2018.

What happens to the current State Highway 1 after the motorway opens?

When the Transport Agency builds new motorways, the roads they replace are often no longer required as state highways. The Transport Agency gives the roads back to a local roading authority – in this case Auckland Transport on behalf of Auckland Council. This handover process is called “revocation”.

The local road between Pūhoi and Warkworth will remain as an alternative route to the new motorway.


When does construction start and when will the motorway be open for traffic?

Construction began in late 2016 and the Pūhoi to Warkworth motorway will open to traffic in late 2021.

What is happening “on the ground” now?

A number of early works are taking place to inform the detailed design and construction of the project.

These include geotechnical investigations, clearing access roads for heavy vehicles and machinery, building site compounds, installing some culverts and clearing forestry in the area north of Moir Hill Road.

We will also be gathering ecological information, salvaging fauna and native plants where necessary and relocating them to new habitats.

Will the project be constructed in stages?

No. The motorway design does not include a connection back to the existing SH1, except for the interchanges at Pūhoi and north of Warkworth. Therefore Pūhoi to Warkworth will be built as one project and not in stages.

What about the people directly affected by construction – noise and so on?

The project’s consent conditions outlined the outcomes to be achieved for noise and other construction and operating environmental impacts. The conditions require the project to measure and report those impacts to demonstrate that NX2 complies.

Early works started in November 2016 and project work will continue until late 2021. During that time, activities that will generate noise and vibration during construction of the road include felling trees, excavating, transporting and compacting soil, drilling, demolishing and removing buildings, constructing bridges, and blasting and crushing rock.

NX2 has developed a Construction and Noise Vibration Management Plan (CNVMP) which highlights the construction noise and vibration standards that must be complied with and details how we will achieve those standards.

The plan identifies what typical construction activities will be undertaken, what typical equipment will be used and the best options for managing noise and vibration resulting from those activities.

In particular, we will:

  • thoroughly assess the potential noise and vibration impacts of the project
  • have plans to minimise them
  • monitor effects on an ongoing basis
  • ensure residents are kept fully informed of what’s happening and when

For each planned activity an assessment will be carried out to find out how much noise and vibration is likely to be generated and who may be affected. These assessments will guide the project’s response to managing the impacts.

We take these obligations very seriously and will consistently do our utmost to reduce any impacts on individuals and local communities.

Will large trucks use key intersections such as Matakana Village or Hill Street intersection? How are you going to manage this?

NX2 appreciates that current traffic issues exist in the area. The Construction Traffic Management Plan (CTMP), which identifies the methods for managing construction-related traffic movements, is currently being finalised. There are specific consent conditions which must be met to minimise the impact of construction-related traffic and ensure that local traffic will not be held up by construction activities for an unreasonable period of time. NX2 is working with Auckland Transport on the details of this plan to ensure that traffic is well managed and our proposals have their approval. At this stage we do not have the detail of specific truck movements. The level of construction traffic that will use key intersections is unknown at this stage because decisions need to be made as to which quarries we source aggregate and rock supplies from. This information will be provided in due course.


How will the environment be protected?

High environmental standards have been set including careful design to minimise impact on kauri and other native forests together with a significant ecological restoration and enhancement programme.

NX2 places great importance on managing the environmental effects of the motorway project by adopting a design which manages and mitigates any adverse impacts by containing sediment, and enhances the local ecology where possible.

Our strategy addresses a range of broad environmental solutions for the project route as a whole, with specific solutions applied to the three geographic sectors (the Warkworth Sector, Moir Hill Sector and Pūhoi Sector) which have distinct landscapes.

The Urban Landscape Design Framework (ULDF) has three high‐level outcomes for the project, which influence our Environmental Management Strategy:

  • A ‘clean, uncluttered’ highway with gentle slopes to blend with the contours of the land and extensive plantings which carry on the natural patterns of vegetation
  • A ‘stitched‐together’ landscape, bringing together streams and landscapes on either side of the motorway, and linking ecological corridors
  • A celebration of the cultural footprint of mana whenua, minimising disruption to natural watercourses, vegetation and landforms

Distinctive natural features will be protected in the landscape. Historical and cultural landmarks will be recognised and highlighted. Plantings will be extensive but in keeping with the landscape on either side of the motorway.

What are the protections for the local ecology?

NX2 is identifying ecological values within the designation (the land area, or ‘corridor’, into which the road must fit) and determining ways to avoid, minimise or mitigate potential impacts from the project.

We will manage potential effects on key ecology, including for example, native bats; freshwater fish; reptiles and amphibians, snails and insects; significant vegetation; wetlands and streams.
As a start point NX2 will use the flexibility offered by the designation to place the motorway so it has the least-possible effect in the most ecologically-sensitive areas – principally the kauri forest located to the west of Perry Road, south of Warkworth.

A viaduct is needed there to cross the stream but instead of the high structure that was originally mooted for the project, NX2 has designed a lower, smaller ‘eco viaduct’ at the edge of the forest.

Not only does this avoid a significant number of trees that were in the original alignment, we mapped the forest to make sure many of the most mature kauri and other native trees were protected. This includes the largest totara tree in the immediate area, plus significant kauri and kahikatea. Overall, this causes the least disturbance to the forest and still allows the ecological corridor and landscape on both sides of the motorway to be connected.

Where habitats of native species will be affected, we will relocate threatened plants and animals into suitable habitats and to undertake extensive native plantings to make up for what is lost.

The planting of natural vegetation to replace any indigenous vegetation lost during the project will be at a ratio of 10-(gain)-to-1-(lost) – one of the largest ratios in any New Zealand roading project. In total, over 100 hectares of mitigation plantings will be undertaken in forests, wetlands, alongside steams, on fill sites and on newly-landscaped areas.

What is Kauri Dieback and how is it being managed?

Kauri Dieback is a deadly fungus-like disease spread via spores in the soil, which can kill kauri trees of all ages. Soil samples are being taken from areas within the project area, to check whether Kauri Dieback is present. Teams working in the forest areas are being given strict instructions on cleaning their footwear to kill Kauri Dieback spores. The disinfectant used is Trigene, a broad-spectrum disinfectant which is non-toxic, non-corrosive, biodegradable and environmentally friendly.

What about sediment and erosion controls, particularly for the Mahurangi and Pūhoi Rivers?

NX2 will focus on controlling the discharge of sediment and mitigating any potential effects on the freshwater and marine environments of the Mahurangi and Pūhoi Rivers and their tributaries.
To minimise these effects, NX2 will be using best-practice erosion and sediment control measures and methods approved by Auckland Council.

Exposed areas of land where work is being undertaken will be limited to ensure sediment generated is kept to a minimum. Areas which give rise to a lot of potential erosion, such as steep areas and highly-erodible soils, will be avoided as much as possible.

Where sediment is generated, a number of measures will be put in place, including ponds where the sediment can settle and be contained, silt fences (fine mesh screens), and diversion drains and earth bunds (land contours which divert fresh water flows away from exposed soil).

A dedicated team of environmental professionals will be deployed in the field to monitor all these measures and Auckland Council will undertake frequent monitoring to ensure the desired standards are met.

How will NX2 minimise the risk of sub-standard steel being used on the project?

We have an Offshore Steel Fabrication Quality Assurance Process that forms the basis of procurement of steel from offshore. Material will be tested and approved prior to fabrication by an approved, qualified third party. Approval of the mill supplying the material will be approved prior to fabrication. This will include witnessing the taking of material samples which will be sent to New Zealand for testing and approval. An approved testing company such as SGS, Bureau Veritas or Lloyds Register will be used. All procedures to be used in fabrication will be approved prior to fabrication and a team of qualified expats based on site in China will inspect every element during the fabrication and coating. Weekly fabrication reports will be forwarded outlining all testing and inspections carried out and the results achieved and verified. Welding will be carried out by approved, coded welders working under AWS D.1. All welding will be fully documented. Approved third-party NDT (non-destructive testing) will be carried out to confirm weld quality during the manufacture. Full product sign off will be achieved based on all quality documentation complying with the defined requirements prior to shipping and all NZ Standards will be complied with. Manufacturer Data Records will be supplied with full weld map for traceability.

Further info

Where can I get more information, ask a question or give feedback to the project?

If your question is not answered here, please email us at or call our NX2 team on 0508 P2WK INFO (0508 7295 4636)