Major wastewater milestone completed in South Auckland

A major milestone has been reached on a South Auckland wastewater upgrade that is expected to support housing growth, reduce overflows, and improve environmental outcomes for local waterways.

Watercare has completed a new 400-metre wastewater pipeline connecting the Archboyd Wastewater Pump Station into the Eastern Interceptor beneath Te Mārua/Boggust Park, Māngere East.

The connection marks one of the most significant construction stages of Watercare’s $64 million Archboyd Wastewater Upgrades underway in Māngere East and Favona.

The Eastern Interceptor is a 19 kilometre trunk pipeline that can carry up to 60 per cent of Auckland’s wastewater to the Māngere Wastewater Treatment Plant.

By diverting wastewater directly into the interceptor, the upgrades are designed to significantly reduce wet weather overflows that have long affected the surrounding area.

The wider project includes construction of a new wastewater pump station at the corner of Archboyd Avenue and Kirkella Crescent, as well as a storage tunnel capable of holding 547,000 litres of wastewater.

During heavy rainfall, excess wastewater can be temporarily stored in the tunnel and then returned to the network once capacity allows.

Manukau Ward councillor Alf Filipaina says the upgrades address long standing constraints in the local wastewater system.

“These upgrades are about tackling long standing capacity issues and making sure our infrastructure keeps pace with a growing population.

“This work will help future proof the network and deliver real benefits for the community, both now and in the years ahead.”

Watercare project manager Jason Salmon says tying the new pipeline into the Eastern Interceptor was one of the most technically complex stages of the programme.

“The work involved carefully excavating to expose the existing interceptor, drilling into its reinforced concrete wall, and carrying out the most critical tasks overnight, when wastewater flows were at their lowest.

“Specialist equipment and detailed planning were required to safely complete the connection and seal it to ensure it was watertight and structurally sound.”

Watercare operations controller Fauzeem Farhaaz says that as part of the wastewater upgrades, Watercare will also remove two existing overflow points - one at Kukume/Wickman Reserve and another at Chalfont Street.

"Although a new emergency overflow point is being installed at Kukume/Wickman Reserve, it will only operate in extreme circumstances.

“For an overflow to occur, several unlikely events would need to happen at the same time, including a complete power outage, both pumps at the station becoming non operational, and the station’s storage capacity being exceeded.”

What’s next?

With the pipeline connection now complete, Watercare will focus on finishing groundworks at the pump station, installing new manholes along Archboyd Avenue, and restoring Te Mārua/Boggust Park, Māngere East.

Landscaping and planting are planned as part of the reinstatement, and the park will be returned to a standard better than before construction began.

This work will include planting native trees to contribute to canopy cover in Māngere, as well as installing a small street garden at the Otago Place entrance. The garden will include a cultural marker - a large kōwhatu (basalt) boulder - gifted by local iwi Te Ākitai Waiohua.

Watercare's goal is to have this programme of work completed by the end of 2027.