A likely four-lane 22km corridor from Whangārei to Port Marsden Highway has been greeted as a much-needed infrastructure upgrade for the most burgeoning region in the country, albeit a four-plus-year traffic disruption in the process.
Whangārei District deputy mayor Greg Innes said the plan, set to start late 2023-early 2024, finishing by 2028, recognised the need to scale safety and efficiency to meet the region's population growth.
"It's good that it's progressing and I think it's absolutely critical because if you have a look at the growth that's occurring in the Whangārei district, it's definitely a requirement in terms of catering for that ongoing growth."
Northland's population has grown faster than any other region largely as a result of Auckland overflow. The upgraded corridor will strengthen the region's transport links with Auckland, supporting the annual movement of two million tonnes of freight between Northland and Auckland.
Four options for the 22km stretch of State Highway 1 (SH1) between Whangārei and Port Marsden Highway (SH15) had been whittled down to two for public consultation.
Feedback received from more than 300 people throughout October showed a high level of support for an upgrade of the existing state highway to four lanes with a separate adjacent walking and cycling path.
People had also signalled a strong desire for safety improvement and protecting the environment.
The second option also proposed upgrading the existing state highway to four lanes with a section built to the west of SH1 to avoid the coastal marine environment at Oakleigh.
Public engagement on the emerging preferred corridor was planned for early 2021 and will involve stakeholder meetings, online engagement and community open days. There will also be a site at the Northland Field Days in March.
Waka Kotahi NZ Transport Agency (NZTA) senior manager project delivery Andrew Thackwray said confirmation of the preferred corridor was set for mid-2021.
"The design of the road within the emerging preferred corridor is at a very early stage of development. Design details, including the form of intersections, access points and location of the shared path, are still to be decided."
However, he said there will be travel time savings due to the additional capacity, along with improved journey time reliability from safety improvements, including a centre median barrier to prevent serious crashes which result in road closures. The extent of the travel time savings would be determined once the design has progressed further in 2021.
The width of the emerging preferred corridor currently varied between 25–250m and would be refined in the coming months through detailed work on the ground and developing designs.
NZTA was also investigating the possibility of "managed lanes". This could include one lane in each direction being prioritised for public transport, freight or multiple occupancy private vehicles.
Innes said council statistics showed the project was needed to help manage strong growth in the area.
"One might have thought that after Covid-19 there might have been a slowing of the growth but the reality is that it's expected that we will reach (a population of) 100,000 next year, given the trend in terms of what we see as a council and building resource consent statistics."
The project was part of the New Zealand Upgrade Programme's $6.8 billion spending to make roads safer and more effective for moving freight.