The pipe that Watercare says was vanalised. Photo: Supplied / Watercare
The latest episode in the ongoing battle between oyster farmers in northern Auckland and Watercare has revealed an engineered overflow point may have been vandalised.
Ten marine farms have been in a seven-year dispute with Watercare to stop sewage overflowing into the Mahurangi Harbour and contaminating their oyster crops.
After each overflow, oyster harvesting was put on hold for 28 days to allow for testing for pathogens like Norovirus.
The marine farmers have been unable to sell any locally grown oysters from the Mahurangi Harbour since Christmas, leaving them on the brink all year.
This week about 40 people who work across the oyster industry in the Mahurangi Harbour, worth nearly $10 million, were let go.
In a statement titled "Vandalism" in response to questions around potential tampering of pipes in Warkworth, Watercare provided RNZ with a photo of the pipe in question which showed a blockage which they claimed was from expanding foam.
"In early July we found that the engineered overflow point into the Mahurangi River near Elizabeth St had been blocked with expanding foam which caused overflows from nearby manholes.
"This was removed by our crews. We have also found bolts missing from a manhole on Elizabeth St and last week replaced the manhole lid with one that is lockable and has a rubber seal," it said.
An oyster farm in Mahurangi Harbour. Photo: Nick Monro
Farmers deny knowledge
RNZ put this information to some of the marine farmers in Mahurangi Harbour, who said they did not know who was responsible for the expanding foam or the missing bolts but did not believe it was a fellow oyster farmer.
"Personally, I don't know of anyone that's blocked the pipe, and that's the honest truth," said Tom Walters of Matakana Oysters.
He said there had been rumours circulating in Warkworth someone had been tampering with manholes and pipes.
"I can imagine they think it was probably us that did it, but it doesn't matter, because it still goes into the river, it still flows downhill, and we're still gonna get closed because of it."
Jim Aitken of Mahurangi Oysters said the culprit could be identified considering the engineered overflow point was in front of a local police station with CCTV.
"I'd be very shocked and surprised if someone went out there to intentionally make the problem worse. If someone's just doing it because they're sick and tired of an organisation not doing their job, that's another thing entirely.
"All I can really say is it sounds like instead of fighting, rushing to address and resolve this issue in a timely manner, Watercare is looking at every possible excuse to not fix it.
"They're looking for every possible excuse to not accept fault, to not take on the responsibility they're supposed to be upholding to the ratepayers and they're now just looking for any sort of excuse to shift claim because if that is sabotage, it's an overflow point," said Aitken.
Tom Walters of Matakana Oysters said despite the blockage being cleared and a temporary solution being applied to the overflow site on Elizabeth Street, it had not stopped the wastewater issue.
"When it overflowed early in the morning last Friday, it was only about nine mils.
"I turned up there at eight o'clock in the morning, a Downer guy is spraying the manholes because there was sewage that had come up from them. Not very much, but enough and they were spraying disinfectant around it.
"So it still occurs, regardless of it being blocked or no," Walters said.
Watercare 'compliant'
Watercare has maintained it is being compliant in Warkworth.
"Watercare is permitted to discharge wastewater at the Elizabeth Street overflow site under the Regional Network Discharge Consent (NDC), which allows for an average of 20.5 wet weather discharges per year (based on a five-year rolling average).
"Watercare remains compliant with the consent. This reflects that we are on a journey to reduce overflows to an average of two or less per year at Elizabeth Street by investing in new infrastructure," a spokesperson said.
A long-term solution to the piping problem on Elizabeth Street in Warkworth is not expected until 2026.
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