Snells Algies Wastewater Pipe and Outfall Construction

Pipes for growth in Mahurangi

PROJECT: Snells Algies Wastewater Pipe and Outfall Construction CONTRACTOR: McConnell Dowell Constructors CLIENT: Watercare Services VALUE: $35.5m

The Snells Algies wastewater pipe and outfall construction project is the first phase of a three-stage scheme to supply the Warkworth and Mahurangi East communities with reliable wastewater services to cater for population growth. The scheme will improve water quality in the Mahurangi Harbour and deliver an upgraded wastewater system.

Watercare awarded the design and construct contract in March 2019. It continues to build on McConnell Dowell’s extensive track record in the construction of wastewater infrastructure and major marine outfall pipelines. Our solution features the use of the Direct Pipe system to install a trenchless pipeline to minimise disruption to the local environment.

McConnell Dowell engaged tunnelling and outfall specialists McMillen Jacobs to develop the permanent works design based on a strong working relationship and technical expertise in marine outfalls and difficult pipeline projects.

The project ran from September 2019 to November 2020. A new world record for the longest Direct Pipe drive by a MTBM of 2021m was successfully achieved, 92m further than the previous world record set McConnell Dowell in 2018 on the Watercare Army Bay Outfall project.