Hill Street intersection improvements Hill Street intersection improvements

The Hill Street intersection is located on State Highway 1 (SH1) in Warkworth. It provides access to the Warkworth town centre and to Kowhai Coast communities including Snells Beach, Algies Bay, Sandspit, Matakana, Omaha, and Leigh.

Project status: Design
Project zone: North

Aerial view showing Hill Street intersection

Project overview

  • The Hill Street intersection in Warkworth is a traffic bottleneck for travellers between Auckland and Northland, Warkworth and the Kowhai Coast communities.
  • The NZ Transport Agency Waka Kotahi (Waka Kotahi) currently owns much of the Hill Street intersection, however when the existing state highway through Warkworth is revoked (following the opening of the Ara Tūhono - Pūhoi to Warkworth motorway) the area will become part of the local road network managed by Auckland Transport (AT).
  • AT and Waka Kotahi agreed in 2017 to work on a joint Single Stage Business Case (SSBC) to investigate a longer-term solution to the Hill Street intersection and to support the prioritisation of the project in the Regional Land Transport Plan (RLTP). 
  • The Hill Street project was prioritised in the RLTP 2021-2031.


Project update

AT is reviewing the SSBC recommended option which considers:

  • the significant land required from Kowhai Park
  • the updated traffic pattern following the completion of the Ara Tūhono - Pūhoi to Warkworth motorway and Te Honohono ki Tai Road (the Matakana link road)
  • the impact of the proposed design to the rain garden that was put in place as a resource consent requirement for the carpark upgrade
  • the requirement for major structures including new retaining walls and the extension of the existing culvert across Sandspit Road, and
  • updated cost estimates.

The design review is to ensure the project could be delivered with the least environmental impact, and to enhance safe walking and cycling facilities. This also provided an opportunity to reduce both the intersection footprint and the construction cost that aligns with the RLTP funding allocation. The review also commissioned updated traffic modelling which showed a 50 percent reduction in traffic volumes on (the existing) SH1 once the Ara Tūhono - Pūhoi to Warkworth motorway and Te Honohono ki Tai Road opened.

A preferred design option is being discussed with key stakeholders prior to public engagement.

Project objectives

  1. Support residential and economic growth by improving journey time reliability through the Hill Street intersection.
  2. Enable growth in the area by ensuring there is sufficient capacity for all modes at the Hill Street intersection to support development.
  3. Maintain journey times for local trips as close as possible to 2023 levels following the opening of the Ara Tūhono - Pūhoi to Warkworth motorway and Te Honohono ki Tai Road.
  4. Ensure accessibility to employment, education, tourism, and core services in and around Warkworth by maintaining journey times for local trips.
  5. Improve walking and cycling choices for trips within Warkworth.



AT and Waka Kotahi agree on a Single Stage Business Case (SSBC) design


Project included in the RLTP 2021-2031

2022 – late 2023

Detailed Investigation, design review, and engagement with key stakeholders


Public consultation


Develop design, obtain consents and secure construction funding

Late 2024 - 2025


Project background

The Hill Street intersection is complex, often confusing, with multiple intersections close to each other. There are safety concerns for all road users including people on vehicles, people walking, and on bikes or other micromobility options. The intersection consists of:

  • the SH1 intersection with Hill Street and Sandspit Road,
  • Sandspit Road intersections with Elizabeth Street, Millstream Place and Matakana Road, and
  • access to Kowhai Park.

Aerial view of Warkworth highlighting the Hill Street intersection

In 2017, Waka Kotahi and AT agreed to investigate a long-term solution to the Hill Street Intersection through a Single Stage Business Case (SSBC). They engaged with stakeholders and the local Warkworth community in 2018 and presented several concept designs during an extensive public consultation. The SSBC was submitted for funding priority in the Regional Land Transport Plan (RLTP) 2021-2031.

For more information on this project

Contact Auckland Transport