Central Interceptor

The largest wastewater project in New Zealand, our super-sized tunnel will run for 16.2kms under Auckland city and the Manukau Harbour. Find out what it’s all about and how we’re tracking.

Duration

2019-2026

Location

Herne Bay to Māngere

Status

Construction

View a snapshot of the project

Join us in celebrating the final moments of the Central Interceptor project with a snapshot of images from Photographer Simon Runting, which documents the massive scale and human effort behind the project.

Auckland’s Central Interceptor is now operational

The Central Interceptor is the largest wastewater infrastructure project in New Zealand’s history. Over seven years, from 2019 to mid-2026, thousands of people worked together to construct 16.2 kilometres of tunnel beneath Auckland, creating critical infrastructure that will protect the city’s waterways and support future generations.

The NZ$1.67 billion project involved some of the most complex underground construction works ever undertaken in New Zealand, including tunnelling between 15 and 110 metres below ground, 17 construction sites and 19 shafts up to 75 metres deep.

The completion of the Central Interceptor was celebrated this week with a final project celebration in central Auckland, bringing together the people and partners who contributed to this landmark achievement. The celebrations concluded with the final blessing ceremony at the Māngere Pump Station, marking the official transition from construction to legacy.

The success of the project was made possible through the commitment and collaboration of thousands of people. More than 4,300 people attended the project’s two-day induction, with teams completing 90,020 training hours, engaging with 4,293 stakeholders and delivering 85 public events throughout construction. The project also prioritised environmental outcomes, with 97% of the 780,470 cubic metres of spoil generated diverted from landfill and 144 trees reinstated.

We congratulate everyone who contributed to the delivery of the Central Interceptor with thanks to the Watercare project team, our joint venture partner Ghella-Abergeldie and their staff members who joined us from around the world, our subcontractors, suppliers, consultants, mana whenua and the Central Auckland community for making this landmark project a reality.

The Central Interceptor will significantly reduce wet-weather wastewater overflows helping protect Central Auckland’s and improve the lives of more than 1 million people for generations to come.

To celebrate the successful conclusion of the project, the Mayor of Auckland hosted a VIP and project team event at the Hyatt Hotel, Wynyard Quarter, on 20 July.

The next day, a karakia and final blessing were held at Watercare’s Māngere Wastewater Treatment Plant, the main construction site for CI, where the project mānea stone was handed back by the GAJV to Watercare as a symbolic last action of the works.

Updates from our sites across Auckland

Dundale Avenue - Construction began: July 2020

Location: Road Reserve near 66 Dundale Avenue, Blockhouse Bay, Auckland 0600

Dundale Avenue is the launch site for the smaller tunnel boring machine that will take flows from the Western Interceptor and connect them to the new Central Interceptor tunnel at May Road.

Central Interceptor

Auckland’s Central Interceptor is now operational

Updates from our sites across Auckland

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