Ghella signs contract for Herne Bay Collector Tunnel with Watercare in Auckland

We’re excited to announce that Ghella has officially signed the Design and Construction contract for the Herne Bay Collector with Watercare in Auckland, New Zealand.

This milestone follows a significant amount of planning, design and pricing work by the team, and marks the transition from development into delivery, with our focus now firmly on safely delivering the project by the end of 2028.

Building on our successful progress and the nearing completion of the Central Interceptor, Ghella will construct the 1.7km-long, 2.1m diameter Herne Bay Collector Tunnel. The project will use the micro TBM previously deployed on the Central Interceptor link sewers, continuing the expertise and specialist tunnelling capability developed on that programme. A large proportion of the original mTBM tunnelling team is now working on Herne Bay, with additional personnel transferring across from the Central Interceptor.

“Working with Watercare has been, and will continue to be, a cornerstone of our long-term commitment in New Zealand, a country where Ghella feels at home” says Country Director @Rosario Barresi.

Since last year, the team has been progressing detailed design following extensive service location investigations. This year, focus has shifted to service relocations and enabling works under separate early works contracts, preparing the corridor for main construction activities.

The project is particularly complex due to its urban setting within a densely populated and established waterfront suburb. With very few cross streets, challenging topography, and properties located just metres from the works, careful planning and coordination will be essential throughout delivery. The pipeline will be constructed beneath local streets at depths ranging from 9 to 22 metres.

The scope includes seven main shafts, three intermediate shafts, overflow connections to existing engineered overflow points, and a control chamber at Pt Erin Park. This chamber will connect the Herne Bay Collector into the Central Interceptor system, forming part of Auckland’s wider wastewater network.

Located adjacent to the Waitematā Harbour, the new infrastructure will significantly reduce wastewater and stormwater overflows into the environment. The Herne Bay area’s beaches are currently subject to frequent overflow events, and this project will play a key role in improving water quality and helping create cleaner, more swimmable beaches for generations to come.

With enabling works already underway, we look forward to continuing our strong partnership with Watercare and working closely with the local community to safely deliver this important project by 2028.