Project introduction

Once complete, the Western Ring Route will be an alternative to Auckland’s State Highway 1, linking Manukau, Auckland, Waitakere and the North Shore, improving network resilience, travel time reliability and bus shoulder lanes, and upgrading cycleway and pedestrian facilities.


The Western Ring Route provides people and freight with a second  route  through Auckland, in addition to State Highway 1. It is one of the government’s Roads of National Significance due to the contribution it will make to regional and national growth.


  • Supports economic transformation as a major freight corridor, enabling goods and services to move safely and more steadily throughout NZ
  • Creates efficient links to and from Auckland Airport, Ports of Auckland and inland freight hubs, to reduce the cost of doing business in Auckland and throughout the country
  • Creates extra motorway capacity, ensuring thousands of vehicles can travel around Auckland. This will also free up local roads by transferring traffic onto the state highway network.
  • Improves the resilience and performance of Auckland’s transport network, protecting our infrastructure against the elements and providing an alternative route in the event of an incident on the network
  • Provides more  transport options including bus lanes, and walking and cycling connections which will  unlock the growth potential of development hubs along the length of the corridor
  • Improves travel time reliability from the west to the south, the north to Manukau and from the city to Auckland Airport
  • Supports the growth aspirations of the Auckland Plan by increasing accessibility to the western suburbs of Auckland, and supporting planned commercial and residential expansion in that area. 

The Western Ring Route Projects

Several projects make up the Western Ring Route.  Those in progress on the Northwestern Motorway were completed and opened in 2016, with the Waterview Connection and Tunnel opened in July 2017, and the final Lincoln to Westgate project will be completed in 2019.

To find out more information about these projects, click on the below individual project websites.

What is the Western Ring Route

The  Western Ring Route is a 48 kilometre motorway alternative to State Highway 1 and the Auckland Harbour Bridge, bypassing the city to the west. It  links Manukau, the city, West Auckland and the North Shore, creating more connections in the transport network, supporting growth and ensuring greater reliability and resilience.

This $2.4b project is the biggest ever to be undertaken by the NZ Transport Agency. 

Completed sections of the Western Ring Route

A number of Western Ring Route projects have been completed and are open for use.  These include:

  • SH18 Greenhithe Deviation

    Construction start: September 2003
    Construction finish: December 2007

    • Four-lane divided motorway from Paul Matthews Drive in the east to the beginning of Upper Harbour Bridge in the west
    • 5.5 km in length
    • Three interchanges and bridges: Albany Highway, Tauhinu Road, Greenhithe Road
    • Together with Upper Harbour Bridge, the motorway creates a new connection between West Auckland and the North Shore
    • Cost - $110 million
    • Opened 2006


    • The project provides a better connection between West Auckland and the North Shore
    • It is one of three projects as part of the Upper Harbour Motorway (SH18) that form the northernmost section of the Western Ring Route – the strategic alternative route linking Albany and Manukau via SH18, SH16 and SH20
    • The new connection increases capacity for motorists travelling to/from the northwest, particularly between Albany and Greenhithe in North Shore City,
    • Greenhithe Deviation provides an easy connection to SH1 and Albany Highway and helps to reduce congestion on local roads in Greenhithe and surrounding areas.

    The interchanges

    Albany Highway Interchange

    • Features a 37 m long bridge with 2 spans and 6 lanes which crosses over the new motorway
    • Interchange provides access for eastbound traffic travelling to join the Northern Motorway (SH1), and westbound traffic travelling from the North Shore to West Auckland
    • Interchange is the major entry and exit point for motorists travelling into the Albany industrial area

    Greenhithe Road Interchange

    • Features a 42 m long bridge with 2 spans carrying Greenhithe Road over the motorway
    • Interchange is the main eastern access into the Greenhithe area from the motorway
    • Traffic travelling from the North Shore can now exit the motorway onto Greenhithe Road
    • Traffic travelling from Greenhithe can now join the motorway and travel to Albany and SH1.

    Tauhinu Road Interchange

    • Features a 47 m long curved bridge with 2 spans to carry Tauhinu Road over the motorway
    • New motorway temporarily ends at this point, until Hobsonville Deviation is completed in 2012
    • Interchange is the main western access into the Greenhithe area from the motorway
    • Traffic from Hobsonville can exit the motorway onto Tauhinu Road and Upper Harbour Drive
    • Traffic from Greenhithe can join the motorway at Tauhinu Road to travel west over Upper Harbour Bridge to West Auckland and the Northwestern Motorway (State Highway 16). 
  • SH18 Upper Harbour Bridge Duplication

    Construction start: February 2003 
    Construction finish: December 2006
    Cost: $35 million


    • The bridge links West Auckland and the North Shore
    • The bridge is one of three projects that form the northernmost section of the Western Ring Route – the strategic alternative route linking Albany and Manukau via SH18, SH16 and SH20
    • The new bridge increases capacity for motorists travelling to/from the northwest, between Hobsonville in West Auckland and Albany on the North Shore
    • The new Upper Harbour Bridge features five lanes – three lanes east towards Greenhithe and two lanes west towards Hobsonville. The extra capacity helps relieve congestion on Upper Harbour Drive


    The NZ Transport Agency is working to protect and enhance the natural, social and physical environment around the project area. This commitment to responsible resource management means comprehensive procedures were put in place to mitigate the effects of the project.

    Coastal Marine area

    Given the project’s location in the environmentally sensitive catchment of the Upper Waitemata Harbour, a number of innovative construction practices were adopted to minimise the impact on the marine environment.

    • Mudcrete – a mixture of cement and soft marine mud at the site was used to complete the foundations below high-tide level on the new Upper Harbour Bridge. It was used in the construction of the widened causeway at the western end of the bridge.
    • 1,400 tonnes of cement were added to 14,000 cubic metres of marine mud to produce the material. By using what is already on site, the mudcrete material reduces the need to import and dispose of excess material.

    Project Partners

    Fletcher Construction Company

    The Fletcher Construction Company is the pre-eminent general contractor in New Zealand and the South Pacific. It has unrivalled depth and breadth of experience across all facets of the construction industry.


    Beca is an international employee-owned engineering and related consultancy services group. Their range of services covers engineering, planning, project management, architecture, GIS and surveying, cost estimating, asset management and valuations.

  • SH16 Westgate Pedestrian and Cycle bridge

    Construction start: February 2012
    Construction finish: January 2013
    Cost: $6 million

    Key features

    • New pedestrian and cycle bridge over the Northwestern Motorway (SH16)
    • Connects Manutewhau Walk Reserve in West Harbour to the Westgate Shopping Centre in Massey
    • The bridge is 209 metres long, 3 metres wide and curved in shape
    • Includes ramps at each end of the bridge for mobility users


    • Provides a safe, new route over the motorway for pedestrians, cyclists and local schoolchildren travelling to Westgate Shopping Centre from the nearby suburbs
    • Provides direct access to the shopping centre, libraries and the developing town centre
    • Features special lighting to highlight the bridge, improving safety at night

    Urban design & the environment

    • Enhancements of the reserve include landscaping and replacing old pine trees with native plants and trees
    • The bridge will be painted yellow, complementing the nearby yellow Clarks Lane Pedestrian and Cycle Bridge, also designed by Jasmax
    • Yellow LED buttons will illuminate the piers and handrail on the bridge
    • New street lights will be installed at the end of the shared pedestrian/cycle path
  • SH20 Maioro Street Interchange

    Construction start: May 2010
    Construction finish: March 2012
    Cost: $40 million

    Key features

    • Half diamond interchange that will connect SH20 Mt Roskill Extension to the SH20 Waterview Connection
    • Maioro Street realigned and extended north to a new signalised intersection with Stoddard Road
    • Eventually the interchange will be developed into a full diamond layout with ramps for both north and southbound traffic


    • Design accommodates any planned expansion of SH20 in the future from four to six lanes
    • Creates a seamless connection between the existing and future Southwestern Motorway
    • Local connections and motorway access established for residents of New Windsor, Mt Roskill and Wesley

    Urban design, environment and public transport

    • Semi-permanent stormwater treatment pond collects and treats motorway runoff
    • A further section of SH20 cycleway added to take cyclists from Ernie Pinches Footbridge through to Maioro Street
    • Additional landscaping and trees throughout the interchange