Watercare apologises for contaminating oyster farms, farmers claim they're 'box ticking'

Watercare says it is extremely sorry that a fault with one its plants saw Auckland oyster farms contaminated and unable to harvest, but farmers claim they're just 'ticking a box'.

The Matakana farmers are devastated yet another sewage overflow into the Mahurangi River has left them unable to collect oysters for 28 days.

Watercare believes a power surge tripped the pumps at Warkworth on Tuesday afternoon, filling up the pump station and then the storm tank.

Then from Wednesday afternoon up until Thursday morning wastewater was entering the stormwater pond.

The failure caused 1200 cubic metres, or about half an olympic swimming pools worth of wastewater to overflow.

Its alert system failed, and an investigation is underway.

The farmers have said they are hurting and going backwards financially.

Watercare chief executive Jamie Sinclair told Checkpoint he would like to publicly apologise for the incident.

"It is devastating, it is devastating for the farmers at this time this season, it should not have happened and we'll be doing a full investigation into what has what has occurred.

"I would like to talk to the farmers or through their advocacy bodies, around how we can provide support to them, but I know this is a very, very tough time."

While Sinclair would not confirm what financial compensation Watercare would offer to the farmers, he said it was something he would like to discuss.

"I would like to talk to them about that - we accept fully that this should not have occurred this and we'll be getting to the bottom of that. But we also want to make sure that it never happens again, and so yes, I want to have that conversation.

"I think that's a fair enough request that clearly is their concern in terms of their financial position at this stage."

Sinclair said they did not know the full extent of the overflow into the Mahurangi River itself, but they would be testing to confirm that.

They were also investigating the failure of the monitoring and alarm system.

"We have a sophisticated system of alarms and for this instance something went wrong and I wanna get to the bottom of that."

Sinclair said the system was made up of multiple alarms.

"All I know is that there are multiple alarms depending on the different instrumentation that exists within those pump stations.

"We do have a monitoring process looking at those alarms on an ongoing basis, but in this instance we need to investigate what has happened."

Watercare opened a new plant in Snells Beach just over a month ago, which they said would go a long way to almost stopping sewage overflows in wet weather that have devastated local oyster farmers.

However the full fix that Watercare said would almost completely cut sewage overflows when it rained was not due to have construction begin until next year.

Sinclair maintained that this was a separate issue.

"The new wastewater treatment plant is an important part of that infrastructure upgrade that I was mentioning before, the improvements that are being made - this is a separate issue to one we've been managing."

While there was no set timeline, he said they hoped to have the investigation finding out as fast as they could.

Sinclair said he had sent a note to the affected farmers and was hoping to hear back in the next couple of days.

Oyster farmers have 'lost faith in Watercare'

Mahurangi Oysters owner Jim Aitken told RNZ that, in an email on Thursday, Watercare informed them of an overflow at its Lucy Moore Memorial Park pump station.

Aitken said continuous pollution of the water had ruined his business.

"We're going under, simple as that. I'm now burning through my personal cash flow. I actually advertised this week for another staff member to help us out over Christmas and next year. I've pulled the pin on the whole thing, I can't afford it.

"It's heartbreaking to see New Zealand, once known for clean, green food production, become unsafe because of repeated spills by Watercare.

"The future we've invested in for our family's legacy and our retirement is going down the drain. Watercare needs to be held to account."

Tom Walters of Matakana Oysters said he was not only concerned about his fellow marine farmers, but also the Mahurangi Harbour environment.

He said the persistent sewage spills would have damaged the harbour's marine ecosystem.

"You'll have oxygen levels depleted and marine organisms that are coming, like snapper that are coming into spawn right now, they'll be affected too.

"Fish, people swimming, kayaking, fishing, boating. It's coming up to that time. We see people out there all the time at the moment bringing boats in.

"They'll have no idea that they're literally playing in a whole bunch of sewage."

Walters said he'd lost faith in Watercare and said their latest apology was "ticking a box".

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