The Ashburton District Council is reassuring residents that all Council-managed drinking water supplies remain compliant with the New Zealand Drinking Water Standards for nitrate levels and the water is safe to drink.

Ashburton District Mayor Neil Brown said that Environment Canterbury’s recent declaration of a nitrate emergency, due to high nitrate levels in Canterbury’s groundwater, has raised community concerns about the public drinking water supply in Ashburton.

“Our Council-managed drinking water supplies are rigorously monitored to ensure they meet the Drinking Water Standards for New Zealand set by the Water Services Authority - Taumata Arowai.”

“We operate 10 community water supplies, servicing around 70 per cent of the district’s population.”

The Maximum Acceptable Value (MAV) for nitrate in drinking water is 50mg/L (equivalent to 11.3mg/L nitrate-nitrogen).

Regular monthly testing sampled from Council’s drinking water supplies shows nitrate-nitrogen levels below this threshold.

All Council supplies are tested regularly for a range of parameters, including nitrates.

The highest average result, in Tinwald at 9.08mg/L, remains within the MAV of 11.3mg/L, and this supply is regularly monitored to ensure continued compliance.

Council encourages private bore owners, especially in rural areas, to test their water regularly, as these supplies are not monitored or treated by Council.

Environment Canterbury mapping showed Ashburton District as having the highest nitrate concentrations from well testing.

“Ensuring safe drinking water is a shared responsibility, and Council remains committed to transparency and proactive management,” the Mayor said.

“We understand that recent headlines may have caused concern. We want to assure residents that their public water supply remains safe, and Council will continue to monitor and share results openly.”

Average nitrate-nitrogen results (last 12 months) at Council’s drinking water treatment plants: