Warkworth to Snells Transfer Pipeline

Customer: Watercare Services Ltd

Contract: Design & Construct

Location: Warkworth, Auckland, New Zealand

Water & Wastewater Solutions New Zealand & Pacific Islands

Fast Facts

  • Dual rising main approximately 1.4 km long
  • Single gravity sewer approximately 3.6 km long
  • Requires 409 steel pipes each 1219 mm diameter and weighing 6.85 tonnes

McConnell Dowell (MCD) was awarded the design and construct contract for the Warkworth to Snells Transfer Pipeline by Watercare in September 2022.

The project is a component of the North-East Wastewater Servicing Scheme to convey wastewater from Warkworth to Snells Beach. The Scheme will cater for future growth and enable Watercare to decommission the existing Warkworth Wastewater Treatment Plant which discharges into the Mahurangi River.

The scope of works includes construction of a five kilometre wastewater pipeline from the upgraded pump station in Lucy Moore Memorial Park transferring the wastewater to a new modern treatment plant at Snells Beach.

The new wastewater transfer pipeline comprises the following:

  • a dual rising main approximately 1.4 km long from the Warkworth Pump Station to a new break chamber, and;
  • a single gravity sewer approximately 3.6 km long from the break chamber to the Snells Beach Wastewater Treatment Plant.

The consented pipeline alignment runs beneath private farmland. Due to the topography and access challenges, the pipeline will be constructed by trenchless means using a Herrenknect Direct Pipe MTBM (micro tunnel boring machine). The pipeline will be installed in three drives involving the construction of two large launch platform sites, one of which will be reconfigured for two of the drives.

Environmental controls and awareness are key to ensuring the team cares for the surrounding environment while construction is underway, this is underpinned by the MCD safety and care value to take care of everyone around us and the environments we work in.

The team have demonstrated a high level of commitment early on in the earthworks when they spotted a dotterel nest in the dirt and a bird hovering nearby. A protective fence was quickly put up around the nest and all operators were alerted to avoid the area to allow for the incubation period of three weeks.

Consultation and communication with invested stakeholders on the project is critical. Relationships have been established early and maintaining on-going consultation with mana whenua, Auckland Council, Rodney Local Board, utility providers and affected landowners will streamline delivery over the lifecycle of the project. The project is due for completion in 2025.

Project Gallery