NZTA Approves $91M for Mill Road Stage 1 to Ease Congestion in South Auckland

South Auckland, identified as the fastest growing area in the Auckland region, is forecast to welcome over 120,000 new residents over the next three decades.

In a major step forward for one of New Zealand’s most vital infrastructure initiatives, Transport Minister Chris Bishop has announced the New Zealand Transport Agency (NZTA) Board’s formal endorsement of the investment case for Stage One of the Mill Road project — a key component of the Government’s Roads of National Significance (RoNS) programme. With $91.1 million now committed for detailed design and consenting work, the long-anticipated project moves closer to reality.

A Vision for Growth in South Auckland

South Auckland, identified as the fastest growing area in the Auckland region, is forecast to welcome over 120,000 new residents over the next three decades. In light of this rapid growth, the Mill Road corridor is positioned as a critical piece of infrastructure to ease congestion, improve travel safety, and open up access to new housing developments.

"Mill Road Stage 1 will serve as a cornerstone of our efforts to enable smarter urban expansion in the Auckland region," Minister Bishop said. "This investment reflects the Government’s commitment to reducing red tape, speeding up delivery, and investing where it matters most."

Project Scope: What’s in Stage 1?

Stage One of the Mill Road corridor, stretching from Manukau to Alfriston, is designed as a four-lane route, including:

• A westbound bus lane at the northern end.

• Two new and six upgraded intersections between the SH1 interchange and Murphys Road.

• Three new roundabouts.

• New bridges over Puhinui Creek and Cheesman’s Bush.

• Conversion of the existing Mill Road (south of Redoubt Road) into a shared path and access road.

The project anticipates major outcomes such as a 30% reduction in corridor congestion, over 60% reduction in serious injuries and fatalities, and 25% quicker journey times by 2031.

Fast-Tracking Delivery: Phased Construction Approach

To bring forward the delivery of benefits, NZTA plans to divide construction into multiple packages. Areas with greater design certainty — particularly those with fewer environmental or technical complications — will be prioritized first.

The construction will begin with Stage 1b (Hollyford Drive to Hilltop Road) and Stage 1d (roundabout improvements around Alfriston). Remaining segments, Stage 1a (SH1 to Hollyford Drive) and Stage 1c (Hilltop Road to north of Alfriston), will follow thereafter.

This staggered construction approach allows teams to begin work as early as mid-2026, delivering earlier benefits to commuters, businesses, and communities in the region.

Historical Context and Future Planning

Mill Road has a long development history, including a confirmed designation for Stage 1 granted back in 2016. The current phase builds on earlier designs with improvements to efficiency, capacity, and resilience.

Simultaneously, technical studies and approval processes for Stages 2 and 3 of the corridor are expected to commence from mid-2026, ensuring long-term strategic planning continues in parallel.

NZTA also intends to seek statutory approvals — potentially via the Fast Track Approvals Act, with further details anticipated in the coming months.

Tolling and Economic Viability

Under the 2024 Government Policy Statement (GPS) on Land Transport, NZTA is required to assess tolling for new RoNS. The Mill Road Stage 1 investment case confirms that tolling is feasible:

• Tolling scenario BCR: 2.2

• Untolled scenario BCR: 3.1

These figures reflect strong economic justification, with toll revenue potentially offsetting construction and long-term maintenance costs. The final decision on tolling is pending Government review.

Looking Ahead: Industry Engagement and Construction Momentum

To keep momentum strong, NZTA has recently opened a Registration of Interest (ROI) for the first technical work package. This marks an important step toward transitioning from planning to physical construction.

Minister Bishop concluded by acknowledging the efforts of local MPs — Hon Judith Collins, Rima Nakhle, and Hon Simeon Brown — for championing the project, and affirmed the Government’s goal to see Mill Road Stage 1 move into full construction without delay.

For further updates and project details, visit the official NZTA Mill Road project page: 🔗 NZTA Mill Road Project