Western Bay of Plenty District Council is pushing ahead with plans to replace the Katikati wastewater outfall pipeline, following a series of failures that have raised environmental and community concerns.

The pipeline, which ran 12km beneath Tauranga Harbour, broke four times in the past six months.

Each repair was complex, costly and high-risk, according to Western Bay of Plenty District Council general manager infrastructure, Brad Singh.

“This is a 12km pipeline buried three metres beneath Tauranga Harbour, and every repair is complex, costly and high-risk,” Singh said.

A map of the current Katikati Wastewater Disposal system. Photo / Western Bay of Plenty District Council

“We’ve reached a point where a long-term solution is essential.”

The Katikati Wastewater Treatment Plant discharged treated wastewater via an ocean outfall pipeline off Matakana Island.

While the pipeline was designed to discharge offshore, leaks along the route meant treated wastewater could enter the harbour in uncontrolled locations, prompting urgent repairs.

The current discharge consent was granted in 2018 for a 20-year term under national resource management rules.

It expires in 2038 and requires the council to confirm a future disposal method by 2026.

The council said it had been working on a long-term solution that would protect the harbour, meet environmental standards and respect cultural values.

Tangata whenua and key stakeholders helped shape an approach that retained the ocean outfall but introduced higher treatment standards.

This option would be consulted on with the community in early 2026 as part of the 2027–2037 Long Term Plan process.

The wastewater outfall project was being considered alongside the Katikati Spatial Plan, which looked at the future of the wider area, including infrastructure, environment and community needs.

“We know the recent leaks have caused concern, and that’s why we’re acting now,” Singh said.

“It’s about finding the right balance – progressing the mahi needed to ensure a future solution is in place within a reasonable timeframe, while still giving the community a clear opportunity to provide feedback on the proposed disposal option.”

Funding for the project had already been included in the council’s current Long Term Plan, with significant investment earmarked for the pipeline replacement.

The current Annual Plan also included budgets for investigations and preparatory work.

The council confirmed it had begun design and consenting work, supported by early engagement with key stakeholders.

In the meantime, it continued to manage risks through enhanced pressure monitoring, flow meters and additional storage solutions to minimise the chance of further leaks.

“This is about future-proofing our infrastructure while respecting the harbour and the communities who rely on it,” Singh said.

More information is available at: https://yourplace.westernbay.govt.nz/katikati-wastewater-disposal