12 Nov 2025

Sewage overflow: $1 million compensation deal struck with oyster farmers

5:46 pm on 12 November 2025
Oyster

Photo: Nick Monro

A million dollar deal has been struck after another sewage overflow hit under-strain oyster farmers north of Auckland.

A power surge tripping pumps at Warkworth sent about 1200 metres of wastewater overflowing, with about half of that thought to have gone into the Mahurangi River.

It meant an almost month-long halt on harvesting and one farmer said he had to dump 60,000 oysters in a week.

A settlement involving short-term relief has been agreed to between Aquaculture New Zealand, the Oyster Industry Association and Watercare.

"This incident has struck at the heart of our oyster farming community," Aquaculture New Zealand chief executive Tee Hale Pennington said.

"Our farmers have endured immense stress and uncertainty through no fault of their own."

Aquaculture New Zealand said the deal gives immediate relief but that it would still be chasing financial settlement for total losses, while demanding systemic changes.

"It is vital that Watercare learns from this disastrous incident and takes appropriate actions and decisions that restores confidence, protects livelihoods, and ensures the ongoing sustainability of the region's marine environment and aquaculture industry," Hale Pennington said.

The latest sewage overflow, believed to be the year's biggest, came at the peak of the season.

Local oyster farmers say they have been battling against sewage issues for seven years.

Watercare said the $1m settlement relates solely to the most recent overflow.

"The incident was caused by a unique chain of events - a power surge that was compounded by our alert system and monitoring not operating as intended," chief executive Jamie Sinclair said.

"We are appointing an external expert to assist us in quantifying the impact on the oyster farmers."

Sinclair said Watercare knows the disruption came at a very challenging time.

Seeking additional compensation

Mahurangi Oyster Association chairperson Lynette Dunn told Checkpoint oyster farmers will be seeking additional compensation on top of the $1m offered.

She said the emotional, physical and mental stress on farmers since the overflow had been huge.

The $1m in compensation will be split between 10 farmers.

"This will provide short term relief for the Mahurangi farmers to get over this little hump, but they're still ongoing financial losses that we still have to deal with.

"We'll be working with Watercare's independent loss assessors to get some financial agreement by the end of the year for the extent of damage that has caused."

Dunn said the timing of the overflow had made it particularly devastating, and was part of the reason farmers would be seeking more from Watercare.

"It is a peak of the time for production for oyster farmers, right throughout the country, we're right on the Christmas time, we've got lots of products that are nice and fat and we need to get that out to make room for a new stock coming in... and we're unable to do that and that's devastating."

The oysters caught at the beginning of the year are going to have to be discarded as they grow too big and begin to die.

She said the additional amount that farmers are seeking is still to be worked out between them and the independent loss assessors.

The damage has not only come in the form of money, but also reputation.

"It's terrible because we've just been down the river this morning from the sewage treatment plant and the river is brown and it stinks."

Dunn said the state of the river was so bad people were asking if there had been another overflow.

Many oyster farmers are apprehensive about harvesting the product they still have in the river.

"The volume of sewerage that has gone in is more that it has ever been before, and as farmers we're worried about when we do harvest, what the consequences could be."

She said the water was last tested on Monday, but there were no results back yet.

The farmers are unsure of when they will be back in business, but Dunn said she could not see it happening before Christmas.

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