Response to Greenpeace testing of water supplies

The Council is aware Greenpeace recently undertook independent testing of water supplies across Canterbury.

They allege that several public water supplies have concerning levels of nitrates present in the samples. In Waimakariri this includes the Oxford Rural No 1 supply.

Council drinking water supplies are tested monthly for nitrates in accordance with the Drinking Water Quality Assurance Rules which sets out source water monitoring requirements.

The results across all Council water supplies are all less than 50 percent of the Maximum Allowable Value (MAV) under the Drinking Water Standards (which aligns with World Health Organisation guidelines), which means they are all less than 5.65 mg/L.

Taumata Arowai as the water services regulator, are responsible for making sure drinking water suppliers provide safe drinking water, have set the MAV for Nitrate-N in drinking water at 11.3mg/L, which is in line with the guidelines from the World Health Organisation and other international standards including the European Union and Australia.

Below are the Nitrate-N results for all our schemes over the last 18 months.

The Nitrate-N Maximum Allowable Value (MAV) in the Drinking Water Standards is 11.3 mg/L – all these results are less 50 percent of this value.

Scheme

Nitrate-N (mg/L)

Min

Max

Cust

0.30

0.37

Garrymere

0.25

1.17

Kaiapoi

0.70

1.93

Mandeville

2.85

4.23

Ohoka

0.35

0.37

Oxford Rural No. 1

4.30

5.02

Oxford Urban & Rural No. 2

1.76

4.22

Rangiora

0.73

0.92

Waikuku Beach

0.26

0.47

West Eyreton

1.64

2.06

Woodend Pegasus

0.00

0.05