Compiled by CORANZ
Environment Canterbury (ECan), has carried a motion to declare a nitrate emergency at its final meeting recently. But the vote was narrowly carried – nine for, seven against – indicating some councillors are in a state of denial.
The motion from Councillor Vicky Southworth called on ECan “to take a leadership role to urgently address the issue of groundwater pollution impacting drinking water sources and supplies”.
Her motion was based on ECan’s recent annual groundwater survey found both E. coli and nitrate concentrations were increasing. The survey found E.Coli in 49 wells – 14% – and mostly in shallow wells. Ten percent of wells had nitrate-nitrogen levels above the Maximum Acceptable Value (MAV) for drinking water, which is 11.3 milligrams per litre.
Gimmicky?
Those opposed councillors and some government ministers have described the motion as a political stunt, despite dozens of protesters gathering outside the ECan building. Agriculture Minister Todd McClay has agreed with those councillors opposed to the motion that the ECan’s decision to declare a nitrate emergency was “gimmicky”.
Minister Todd McClay calls ECan concern “gimmicky”
But seeming to have “a bob each way” he added that he didn’t want to distract from the wider point that “we’re all working hard to improve water quality” and too much nitrogen was a problem and can be in many parts of the country.”
Comprehensive
But another much more comprehensive study indeed arguably New Zealand’s largest study into nitrates in drinking water, strongly points to a widespread threat to freshwater quality.
The new study, led by Earth Sciences New Zealand, analysed more than 2,400 rural drinking water samples around the country between 2022 and 2024.
Canterbury, Waikato and Southland had the highest amounts of contamination and seven other regions were identified as having “emerging” nitrate issues.
Danish Study
Multiple academic studies had linked high nitrate in drinking water to fatal blue baby syndrome, cancer and pregnancy risks.
A major Danish study (Schullehner et al., 2018) involving 2.7 million people over 23 years found a statistically significant link between long-term nitrate exposure in drinking water and increased colorectal cancer (CRC) risk, even at levels well below current international safety standards (like NZ’s 11.3 mg/L).
The risk increased with higher nitrate levels (e.g., 15% higher at >2.1 ppm), suggesting nitrates convert to carcinogenic N-nitroso compounds in the body, prompting calls for lowering drinking water standards globally, as benefits significantly outweigh costs.
Bowel Cancer
According to Bowel Cancer NZ, around 3,000 New Zealanders are diagnosed with bowel cancer each year. Approximately 1,200 Kiwis will lose their lives to the disease, as many as breast and prostate cancer combined.
But as to cause of nitrates in drinking water, it’s not only cows, but industry too.
Back in 2021 Radio NZ reported that nitrogen-containing wastewater from a Fonterra factory had contaminated the private water bores of people living nearby and some farms where wastewater is spread.
One Cambridge couple had nitrate levels exceeding New Zealand’s drinking water standards.
At the time, Otago University’s Dr Tim Chambers was reported as saying New Zealand should take a precautionary approach and reduce the maximum level from 11.3mg/L to 1mg/L.
I just don’t not follow the attitude of some councillors. The Danish study showing bowel cancer links to high levels of nitrates in drinking water was very comprehensive, over 23 years, of 2.7 million people (that is hal; NZ’s population). Councillors voting against lowering nitrate levels are dicing with human health.
Isn’t Canterbury or south Canterbury the highest for bowel cancer incidence – or among the highest – in the world?
That is to also add the contamination of waterways as high nitrate levels are toxic to native fish and trout and salmon and no doubt invertebrate life, i.e. the whole freshwater ecosystem. Is not the name Environment Canterbury (ECan) about clean, fully flowing waterways?
Perhaps some councillors and government ministers need reminding of these facts.
Well said ! Nitrate in our Water ? It’s actually “Bowl Cancer ” on TAP .
Nitrate levels over 3 mg/l are too high for long-term exposure. The WHO level of 11.3 mg/l is for short-term exposure and is the current legal limit. It is way too high for long-term exposure. Many parts of Canterbury are routinely over 3 mg/l. For example,
if you live in Rangiora, Ashburton, Hinds, Orari or Glenavy, you should only drink rainwater or bottled water. The nitrate levels in these town supplies are routinely high (over 3 mg/l), and you are at risk of bowel cancer and other nitrate-related conditions. Same for private bores in lower-Canterbury plains areas. There is a potential public health crisis about to happen in Canterbury, especially with bowel cancer.
You have been warned…
Interesting that the highest nitrate findings are in three areas known for their dairy farming. Waikato and Southland have always been. Then Canterbury was facilitated to dairy using irrigation on their very porous soils, with the state takeover of Ecan by the John Key National Government in 2009. Short term profits for long term problems.
Tragic with the Selwyn River ? Drained & Polluted , that was a World Class Trout Fishery with many Overseas Fisherman that used to arrive ! all gone now & on the other hand we hand Sir COMIC Key , who didn’t know if he was Arthur or Martha , promoting Clean & Green N.Z Tourism ? The Overseas Fisherman mostly from the U.S. spent up Big Time .