New Zealand’s Largest Wastewater Tunnel One Step Closer to Start Date

By TBM News May 21, 2018

The start of construction of the largest -ever project for Watercare, Auckland, New Zealand’s water utility, is one step closer with the issuing of the request for proposal. Four construction contractors, short-listed earlier this year, now have four months to prepare their proposals.

The Central Interceptor – a 4.5-m diameter wastewater tunnel – is designed to help reduce combined wastewater/stormwater overflows to local waterways and the Waitematā Harbour, along with providing system resilience and additional network capacity for a growing Auckland.

With construction set to start in 2019, the $1.2 billion ($830 million US) Central Interceptor is one of New Zealand’s most ambitious tunneling projects. Constructed at depths of up to 110 m, the tunnel will run 13 km between Western Springs and the Māngere Wastewater Treatment Plant. Connecting to existing networks along the route, flows and overflows will be diverted into the tunnel before it crosses the Manukau Harbour below the seabed.

Shayne Cunis, Executive Program Director for the Central Interceptor, is happy with progress made during the procurement phase. “We’re running a tight ship here. Keeping to schedule on this critical project is crucial for the industry. There is a lot at stake – these contractors and all interested parties need certainty and confidence in the process and timeframe. Our intention has always been to stick to our plan. We do what we say and the people of Auckland can take comfort that Watercare is delivering on its promises of improving Auckland’s infrastructure.”

With 500 pages of RFP documentation, coupled with some 2,000 technical documents, in hand, the short-listed construction contractors will now be fully briefed on the project before an official tour of the tunnel route later this month.

The contractors’ proposals are due Sept. 14, and the winning bid will be announced in February 2019.

Short-listed contractors are: CPB Contractors, Ghella-Abergeldie Harker Joint Venture, Pacific Networks, comprising McConnell Dowell, Fletcher Construction and Obayash, VINCI Joint Venture, comprising VINCI Construction Grands Projets, HEB Construction and Solentache Bachy.