Last updated: 27 June 2025
State Highway 16 (SH16) is an important link for the North West Auckland community. As the region continues to grow, with more homes being developed and new businesses expanding, traffic volumes are increasing, putting added pressure on our network and highlighting the need for improved efficiency.
The section of SH16 between Brigham Creek and Waimauku also needs to be made safer. Between 2010 and 2022, 3 people were killed, 31 people were seriously injured and several have sustained minor injuries on this stretch of road. This makes it a high risk road.
That’s why the focus of this project is to improve safety and efficiency in the area which will improve the wider transport network’s effectiveness.
To make SH16 safer and efficient, we’re making a number of improvements.
Stage two:Brigham Creek to Kumeū
Between Brigham Creek and Taupaki roundabout we’re adding extra lanes, so there will be a total of four lanes (two in each direction). We’re improving the intersection by installing a roundabout at SH16/Coatesville-Riverhead Highway to make it safer for all users. We’re constructing a shared path for walking and cycling between Brigham Creek and Kumeū to increase transport choice, this will include safe pedestrian crossing facilities.
Safety infrastructure(external link)
We’ve split the project into two stages. Stage one runs from Huapai to Waimauku and stage two is between the Brigham Creek roundabout to Kumeū.
Stage one is currently under construction and is expected to be complete by the end of 2025.
With the revised project costs confirmed for Stage two we are now underway with landowner engagement and property acquisition so this stage of the project can proceed to construction.
Between Huapai and Waimauku the improvements along this stretch of road include wider road shoulders. They are wider than the minimum standard to make it safer for people who walk or bike.
Between Brigham Creek and Kumeū there will be a shared path. This was consulted on with the community in 2018 and received wide support.
Read a summary of the feedback [PDF, 158 KB](external link)
The roundabout will be designed to provide safe walking and cycling paths to circulate the roundabout, clear of traffic, and have designated safe crossing points through the islands.
The project team is also working to ensure improvements are designed to accommodate any future plans that support walking and cycling.
The shared path will be on the southern side of SH16. This side allows for better and safer access into connecting facilities. This side also had less safety issues for people to navigate e.g. driveways and intersections.
View the project map [PDF, 334 KB](external link)
The addition of a dedicated shared path will provide people with greater choice in how they move about. It will make it safer for people walking and on bikes, as well as providing better and safer access to public transport. This will become even more important as the area continues to grow in the future.
During public consultation in 2018, 81% of people said they supported plans for a separated shared user path. This, along with the 2018 Government Policy Statement, led to the inclusion of the walking and cycling path between Brigham Creek roundabout and Kumeū. This increases the transport options available for people, benefits our environment, and it’s good for our health.
For Stage two, crossing points near new and existing roundabouts between Brigham Creek and Taupaki are proposed, to enable people walking and cycling along the new shared path to safely cross the highway to access bus stops and other key destinations.
We have engaged a range of specialists and also an independent Road Safety Audit team to review the whole project including the crossings. Based on feedback and recommendation from these specialists the following crossings are included in the design:
For Stage one, we are installing a pedestrian refuge island between Wintour Road and Factory Road to allow people to safely cross and access the existing bus stop. There will also be a new concrete footpath on the northern side of SH16 between the bus stop and crossing, and on the southern side at the corner of Wintour Road.
Between Brigham Creek to Kumeū we have considered a range of options to get people across the highway safely while balancing the movement of vehicles. The options considered include unsignalised, unraised crossings and grade separated alternatives such as an overbridge.
Grade separation (such as an overbridge or underbridge) would cost significantly more than a signalised crossing. Building 3 pedestrian bridges would create a larger footprint, which would require additional design work, property acquisition, earthworks and materials. There would also be more traffic disruption during construction. The height and span of any bridge would also need to account for oversized vehicles.
We know that congestion is an issue along SH16 and can cause frustration for those who live and travel along the corridor every day. While it is important to maintain the flow of vehicles through this corridor, we also need to improve safety for all road users, especially those who are most vulnerable. As well as being tragic for all involved, crashes result in disruption to the network and add to congestion.
Traffic modelling has been undertaken and congestion issues have been considered as part of the design. Congestion resulting from the new signalised pedestrian crossings is heavily dependent on how many people are using the crossing at any one time.
This project is to improve safety along this section of state highway. The safety improvements will help to increase efficiency of the overall network by:
Auckland Council, Auckland Transport and Waka Kotahi NZ Transport Agency are working together to investigate options to address future growth in Auckland’s North West.
Investigations have indicated an alternative route may be more effective in addressing the capacity issues for Kumeū-Huapai than four laning the existing SH16. Modelling has shown that with an alternative route, four laning past Taupaki is not required in the future.
Any future projects, such as an alternative route to SH16 and a new public transport network, need significant planning and consenting to be finished before any work can start.
You can learn more about the long-term programme of work by visiting Supporting Growth's Northwest Auckland page.
Supporting Growth - Northwest Auckland
A dedicated left turn slip lane on the Coatesville-Riverhead Highway approach to the roundabout was considered during the early stages of the project. This option was not progressed as it did not address the safety issues because slip lanes encourage merging at higher speeds. In this instance, it also makes it unsafe for pedestrians and cyclists who want to cross the roundabout. In order to incorporate a slip lane, the proposed roundabout footprint would have to be made larger to allow for vehicles to safely merge and provide adequate sight distance. An extensive amount of property would also be needed.
Our traffic team have undertaken modelling of the proposed roundabout to understand its performance. The modelling is a way to predict how the roundabout will function after it is built. The model findings showed the vehicle delays and queues, on all legs of the roundabout, would be acceptable. The approaches to the roundabout will be designed so drivers have to slow down, which in turn creates gaps in the flow of traffic, allowing other vehicles opportunities to enter the roundabout from adjacent approaches. Unlike the current intersection, there is no incentive for traffic coming from Kumeū to slow down or create safe gaps for those turning from the side road.
We have planned our safety improvements so that we avoid the need to buy land where possible.
Stage one required strip acquisition, where we purchased small strips of land to allow us to widen the corridor to implement the safety improvements. We worked directly with impacted landowners through this process.
For Stage two will require some land. We are working directly with impacted landowners through this process.
Someone from our team has contacted every landowner whose property may be affected. This includes both landowners whose land might be needed for the project and landowners whose driveway access might be affected during construction.
We’ll also send out information to everyone within the project area so that people know what’s happening and have the chance to talk with our team.
We’ll talk to people whose land is affected about the process and their options once we’ve confirmed whether any of their land is needed. But if you do want to find out more, you can find information on the Land Information New Zealand (LINZ) website.
Land Information New Zealand (LINZ)(external link)(external link)
You don’t need to worry about utilities like water pipes and power cables that the council or power company has put in within the road boundaries. If you have a utility that you’ve had put in yourself, then we might need to talk to you.