Waiwera upgrades reach milestone, bringing cleaner waterways one step closer

A major step towards restoring the health of the Waiwera Estuary has been achieved with the installation of a new submersible pump station, the centrepiece of Watercare's $45 million Waiwera water and wastewater upgrade programme.

On track to be operational later this year, the pump station will work alongside a new 4.5km wastewater pipeline to transfer wastewater from Waiwera to the Army Bay Wastewater Treatment Plant.

The upgrade will enable wastewater from Waiwera to be treated at Army Bay rather than at the existing Waiwera Wastewater Treatment Plant, where treated wastewater is currently being discharged into the estuary.

This change will permanently end treated wastewater discharges into the estuary, significantly improving water quality in one of Auckland's most sensitive coastal environments for the community to enjoy now and into the future.

Hibiscus and Bays Local Board chair Alexis Poppelbaum says the project will deliver lasting benefits for the environment and the local community.

"Ending treated wastewater discharges into the Waiwera Estuary is a major win for water quality and the local environment.

"The new pump station and pipeline will allow wastewater to be treated to a higher standard at Army Bay, while the existing ponds at Waiwera will provide storage to support the new wastewater system.

"This is an important investment in the long-term health of the estuary and the wider community."

Watercare senior project manager Paul Thorn says months of planning and preparation culminated in a carefully coordinated installation involving a 400-tonne crane.

"The pump station structure and its components were installed in a single day after being preassembled by our contractor, Fulton Hogan, and transported to site.

"The inlet structure, which manages wastewater flows as they enter the pump station, was installed first. Later that afternoon, the pump station and its dry and wet wells were lowered into place."

Thorn says the decision to use a preassembled pump station accelerated construction while minimising disruption to the operation of the existing wastewater ponds and preparing them for their future role as storage ponds.

"By reusing the existing ponds, we can maximise their combined storage capacity of 17,500 cubic metres, roughly the equivalent of seven Olympic-sized swimming pools.

"The additional storage will improve the resilience and operation of the wastewater network, particularly during peak flows and wet weather events."

The Waiwera upgrades form part of Watercare's 10-year, $15.2 billion infrastructure programme, which will deliver more than 1,000 infrastructure projects across Auckland to support growth, improve environmental outcomes and build resilience for future generations.

Watermain and wastewater main progress update

Work on both the new wastewater and water pipelines is progressing well and remains on track for completion by the end of the year.

Installation of the new watermain has been completed, with final connections now being planned between Waiwera township and the reservoirs atop Waiwera Hill.

Once operational, the new watermain will improve the resilience and reliability of the local water supply by replacing ageing infrastructure that has reached the end of its service life.

Significant progress is also being made on the wastewater pipeline, with crews installing the gravity main between Hatfields Beach and the Hatfields Wastewater Pump Station.