Another setback for Mahurangi oyster farmers

Another setback for Mahurangi oyster farmers

Mahurangi oyster farmers are devastated following yet another wastewater overflow into the Mahurangi River.

Watercare confirmed that a power surge on 29 October tripped pumps at the Warkworth treatment plant, causing approximately 1,200 cubic metres of wastewater to spill into the river. Due to a failure in Watercare’s alert system, the overflow went undetected for nearly 24 hours.

The timing of the spill was particularly damaging, coinciding with the final peak of the harvest season. Each contamination event triggers a mandatory 28-day harvest stand-down, compounding the financial strain already facing farmers.

Watercare Chief Executive Jamie Sinclair has apologised to the farmers and confirmed an investigation is underway into both the cause of the incident and the failure of the monitoring and alarm systems.

Aquaculture New Zealand (AQNZ) and the New Zealand Oyster Industry Association (OIA) are in discussions with Watercare to secure financial support for affected Mahurangi oyster farmers.

They are seeking financial relief to cover income losses, infrastructure damage, and essential farm maintenance — support that is vital to help farmers recover and prepare for the 2026 oyster season.

Read more about Negligence in the harbour: how pollution is crippling oyster farming in Mahurangi