Residents in Beachlands and Maraetai will benefit from a more reliable wastewater network, with Watercare completing the relining of 6.2 kilometres of local pipes.

The renewed pipes will prevent groundwater and seawater from entering the network, which can overwhelm the system, increase flows to the treatment plant, and contribute to wastewater overflows.

The work is part of a targeted $12 million wastewater renewals programme aimed at strengthening network resilience and addressing issues across Auckland’s 8800-kilometre wastewater network.

This programme is one of several proactive renewal initiatives Watercare is delivering as part of its $13.8billion capital delivery programme (2025–2034). More than half of this investment - $6.98billion - is dedicated to renewing and upgrading water and wastewater networks in communities like Beachlands and Maraetai.

Watercare head of sustainability and innovation Brendon Harkness says the programme prioritised Beachlands and Maraetai due to their history of inflow and infiltration problems.

“Inflow is caused by things like illegal stormwater connections, poorly sealed manholes, cross-connections, and low gully traps that lead to spikes in peak flows.

“Infiltration occurs when stormwater enters the network through cracks, deteriorated joints, and damaged household connections.

“Beachlands and Maraetai had clear signs of these issues, and the pipes needed remedial work.”

Watercare project manager Isileli Aholelei says construction partners CB Civil and NZ Lining carried out CCTV investigations to assess the condition of the pipes.

“These inspections showed many sections were in poor condition, with cracks and defects allowing groundwater, seawater, rainwater, debris and even small branches to enter the system."

Aholelei says the investigation findings prompted Watercare to significantly expand the original scope of work.

“Once we assessed the footage, it became clear we needed to go beyond the initial 1.9 kilometres planned.

“The scope eventually grew to 5.8 kilometres and later increased again. We also rehabilitated 85 manholes and 198 household connections.”

After flushing the network to remove debris, the pipes were relined using a trenchless cured-in-place pipe method.

Aholelei says trenchless relining provides major benefits.

“It lets us fix damaged pipes without digging - and helps make the network more reliable, reduces disruption for the community, lowers costs, and helps the pipes last longer.

“As part of the wider renewals programme, Watercare is also carrying out pipeline investigations and renewals in Newmarket and west Auckland. These works are expected to wrap up by March 2026.”

About Watercare

Every day, we supply about 440 million litres of safe drinking water to 1.7 million people in Auckland. We also collect and treat their wastewater.

Over the next 10 years, we will carry out more than 1000 projects to improve and expand our water and wastewater infrastructure – investing an average of $3.8 million every day ($13.8 billion in total).

Our infrastructure investment programme will help to keep our precious environment healthy by reducing the frequency of wastewater overflows onto land and into waterways.

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