Source: Greenpeace
Greenpeace will be offering free drop-in water testing for nitrate-impacted Glenavy residents near Waimate, and on the same day host a public meeting on nitrate contamination with public health researcher Dr Tim Chambers at the Glenavy Hall on Tuesday 15 November at 7pm.
Dr Chambers has co-authored published research on the health impacts of nitrate including a paper estimating 100 cases of colorectal cancer and 40 deaths per year were attributable to the contaminant.
“There is increasing evidence linking exposure to nitrate in drinking water to multiple negative health outcomes, including colorectal cancer, preterm births and neural tube defects. In many studies, the risk of the adverse health outcome was found to occur at drinking water nitrate levels significantly lower than New Zealand’s Drinking Water Standard of 11.3mg/L,” says Chambers.
In August this year Emergency drinking water supplies were installed in parts of the Waimate District after nitrate levels exceeded the Drinking Water Standards.
Greenpeace has been undertaking free town-hall water testing events since winter 2021 and has also run a free mail-in nitrate testing service having now tested over 1500 household bore water samples.
“Access to safe drinking water is a basic human right,” says Greenpeace Senior Campaigner Steve Abel, “it is unacceptable that the people of the Waimate region have lost their water supply because of nitrate contamination, and local residents deserve information and answers.”
While it’s well understood that worsening nitrate contamination of drinking water is caused by a sevenfold increase in synthetic nitrogen fertiliser use and a 10-fold increase in dairy intensity across Canterbury over the past 30 years, Dr Chambers says the local dairy factory may also be playing a role in the Waimate nitrate-spike.
“Looking at well data obtained from ECAN by Otago University on the specific issue in Waimate and Glenavy, it looks like the Oceania Dairy Factory could be playing a part with its nitrogen-rich wastewater,” says Chambers.
“The data shows that a steady increase in nitrate in local wells corresponds with the dairy factory getting consent to discharge to land in 2015. There is also an increase in calcium and hardness which indicates dairy factory waste – predominantly whey – is potentially contaminating the wells,” says Chambers.
Dr Chambers says, “more scientific work needs to be done to establish the specific cause and the contribution of any land use practice.”
