Frequently Asked Questions

  1. What is the Manukau Harbour Crossing?
  2. Why is the project needed?
  3. What benefits will the project deliver?
  4. What are the main components of the project?
  5. Why is the Rimu Road bridge being replaced?
  6. Who is constructing the Manukau Harbour Crossing?
  7. How long will it take to complete the project?
  8. How is the community being kept informed?
  9. How will I find out about construction happening in my neighbourhood?

1. What is the Manukau Harbour Crossing Project?

The $230M Manukau Harbour Crossing Project is a New Zealand Government initiative to upgrade State Highway 20 between Mangere and Onehunga in Auckland. It involves:

  • Building a new bridge over the Manukau Harbour, alongside the existing Mangere Bridge
  • Widening the motorway either side of the bridge – to Queenstown Road in the north and to Walmsley Road in the south
  • Improving local walking and cycling links.

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2. Why is the project needed?

The project is essential to the continued growth and economic development in the Auckland region. It will relieve congestion and improve safety on a route that is strategically important to the region’s future.

In particular, it will contribute to completion of the Western Ring Route which will provide an alternative to SH1 and the Auckland Harbour Bridge for road travel through metropolitan Auckland. Once completed, the Western Ring Route will provide 48km of motorway from Manukau in the south to Albany in the north via SH20, SH16 and SH18.

Also, the project will provide much needed additional capacity on the main route between central Auckland and the Auckland Airport.

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3. What benefits will the project deliver?

The project will:

  • Provide safer, quicker trips for more vehicles on SH20 between Mangere and Onehunga
  • Improve access between south and central Auckland
  • Improve travel times to and from the Auckland Airport
  • Provide better walking and cycling links north and south of the crossing
  • Enhance the motorway with extensive landscaping and planting
  • Contribute to better links for business and freight between key industrial hubs in the cities of Manukau, Auckland, Waitakere and North Shore.

4. What are the main components of the project?

1. Duplicate Mangere Bridge. A new bridge is being built to the east and at the same level as the existing Mangere Bridge. It will carry four lanes for southbound traffic and a bus shoulder lane. The existing bridge will be reconfigured to carry four northbound lanes and a bus shoulder lane.

2. North of the bridge. The motorway is being widened to three traffic lanes and a bus shoulder lane in each direction. At Queenstown Road, it will connect with the SH20 Mt Roskill Extension.

3. South of the bridge The motorway is being widened to three traffic lanes and a bus shoulder lane in each direction. To enable this to happen, the Rimu Road motorway overbridge and the Hastie Avenue footbridge will be replaced. Also, the Tararata Creek bridge will be widened.

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5. Why is the Rimu Road bridge being replaced?

Rimu Road bridge provides a critical east-west link over the motorway between Mahunga Avenue and the Mangere Bridge village. However, it is too narrow to allow for the widened motorway to pass under it. It is therefore being replaced.

The new Rimu Road bridge is due for completion in mid-2009. It will carry one eastbound lane and two westbound lanes – one for traffic turning onto the motorway and the other for traffic going on to Mangere Bridge village. It will also have a cycle lane and a footpath for pedestrians.

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6. Who is constructing the Manukau Harbour Crossing?

The project is being delivered by the Manukau Harbour Crossing Alliance comprising the NZ Transport Agency, Fletcher Construction, Beca Infrastructure and Higgins Contractors.

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7. How long will it take to complete the project?

Physical works began in January 2008 on the south side of the existing Mangere Bridge. The project is due for completion in early 2011, in time for the 2011 World Rugby Cup.

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8. How is the community being kept informed?

Our Community Relations Team works to keep the community informed about construction progress through:

  • Two community liaison groups – one for Mangere Bridge and one for Onehunga – that meet regularly with the project team. At these meetings members receive up to date information about the project and provide input on issues that might affect their communities.
  • An information kiosk at the Manukau Harbour Crossing Project site office in Waterfront Road, Mangere Bridge. It has a display that includes a model of the project. The kiosk is open Mondays to Fridays from 8am to 5pm.
  • Our website: www.nzta.govt.nz/manukaucrossing
  • Our 0800 number, which people can call any time, 7 days a week.
  • Traffic bulletins, which provide information about any traffic changes proposed in the week ahead. They are posted on our website, and are also emailed to people who want to receive them. Contact us if you'd like to receive them.

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9. How will I find out about construction happening in my neighbourhood?

If any significant new activity is planned for your area, we will let you know either by contacting you personally or leaving information in your letterbox. If you have any questions or concerns you should contact the project on Ph 0800 7420 649.

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