Mahurangi Harbour in Warkworth, Auckland, New Zealand, where the wastewater overflow affected oyster farms.
Photo: Adobe Stock.
Watercare, the provider of drinking water and wastewater services for Auckland residents, announced the immediate compensation payment of NZD 1 million to Aquaculture New Zealand for distribution to the ten oyster farmers impacted by the wastewater overflow in Mahurangi Harbour on October 28.
The payment comes after talks between Aquaculture New Zealand (AQNZ) and the New Zealand Oyster Industry Association (NZOIA) with Watercare regarding what AQNZ described as "the recent significant wastewater overflow and its devastating impacts on Mahurangi oyster farmers and the marine environment."
Both organizations have acknowledged what they described as "Watercare's constructive engagement, commitment to initial financial relief, and an agreed process to determine total losses for the farmers."
This recognition has also come from the New Zealand Government through the Parliamentary Under-Secretary for Oceans and Fisheries, Jenny Marcroft, who said that the NZD 1 million payment is "a welcome first step," although she added that more is needed.
Both Watercare and Aquaculture New Zealand will work together to reach a final resolution through an external assessment process.
Regarding the incident, Watercare confirmed that an electrical surge on October 28 deactivated the pumps at the Warkworth treatment plant, causing the storage tank to fill up, which led to a sewage overflow from Wednesday afternoon to Thursday morning (October 29-30). As a result, approximately 1,200 cubic meters of wastewater were discharged into the Mahurangi River.
Due to a failure in Watercare's alert system, the overflow went unnoticed for nearly 24 hours, delaying Watercare's response and exacerbating the environmental and economic damage to Mahurangi oyster farmers, who were significantly affected as the spill occurred at a crucial time: the final peak of the oyster harvest season.
"This incident has struck at the heart of our oyster farming community," said Tee Hale Pennington, Chief Executive of Aquaculture New Zealand. "Our farmers have endured immense stress and uncertainty through no fault of their own."
As explained by AQNZ, each contamination event triggers a mandatory 28-day harvesting ban, causing serious economic losses to farmers. However, according to the organization—and also according to the NZ Parliamentary Under-Secretary for Oceans and Fisheries—this is not the first incident of this type to occur in the area.
On its website, Aquaculture New Zealand states that in 2025 alone, there have been 32 spills, resulting in 180 days of closure and more than 3,500 cubic meters of wastewater discharged into the water.
"It was once a pristine estuarine environment and a cornerstone of Aotearoa's aquaculture industry but now Mahurangi Harbour, north of Auckland, is facing an ecological and economic crisis," claims AQNZ.
For his part, Watercare Chief Executive Jamie Sinclair stated that the payment relates solely to the most recent overflow, which he said was caused "by a unique chain of events," for which the company has committed to rectifying the situation.
"I've written to the farmers to reiterate my apology and confirm the payment of NZD 1 million, as well as inform them of the external assessment process. After the incident, I said we were committed to making things right, and we've worked quickly to turn that commitment into action," Sinclair continued.
"We know this disruption comes at a very challenging time, just as the harvest season was at its peak. Today's payment is intended to provide immediate support, and we hope to have the assessment process complete before Christmas," Watercare's Chief Executive added.
As mentioned above, the rapid response of the water treatment company was applauded by the New Zealand Government, which nevertheless asked for more.
"I applaud Mr Sinclair and Watercare for this speedy response to the problem of sewage overflow into the harbour, which followed a power surge tripping pumps," said NZ Parliamentary Under-Secretary for Oceans and Fisheries Jenny Marcroft.
"However, this latest incident came at a time when the farmers are at the peak of harvest time, and already right on the edge due to multiple previous sewage overflow incidents over a number of years," she added.
"More compensation is clearly needed. I urge Watercare to continue to work constructively with Aquaculture NZ to fully compensate these farmers for the financial hits they are repeatedly taking, and the personal toll it is taking on them and their families," Marcroft continued.
Meanwhile, Aquaculture New Zealand said that while this agreement provides some immediate relief, it will continue to seek a financial settlement that covers the full losses of farmers and also systemic changes that prevent these failures from happening again.
"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," said Hale Pennington.
"We remain steadfast in our support of the Mahurangi oyster farmers as they confront both the immediate and long-term consequences from failures in Watercare's systems and infrastructure," AQNZ Chief Executive added.
AQNZ and NZOIA claimed that they will continue to advocate for Watercare to financially settle all losses incurred by farmers before the end of the year. The aquaculture organization also said that work is continuing to quantify the total magnitude of losses resulting from Watercare's system failures.
Aquaculture New Zealand emphasized that this includes the long-term reputational repercussions for the Mahurangi oyster industry. This need to clarify the incident for the general public was also highlighted by Jenny Marcroft.
"This is devastating enough for the farmers and the local oyster industry, but the public should also be extremely concerned that their waterways are being polluted with wastewater. The sea is our food basket and our playground. No sewage should ever be flowing into it," NZ Parliamentary Under-Secretary for Oceans and Fisheries concluded.