Iron
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Drinking Water Quality Testing - Iron
Iron is one of the most abundant metals found on earth, making it often present in drinking water. This does not present a health risk. Iron at levels above the aesthetic value can cause staining of laundry and sanitary ware and cause water to have a metallic taste.
This page shows the Selwyn's District Council's testing results for iron for water sources used for drinking water measured in g/m3. The drinking water authority Taumata Arowai has set an aesthetic value for characteristics that relate to acceptability of drinking water to consumers (such as appearance, taste, or odour).
Select a scheme boundary to find the most recent iron result for each source. Data is updated monthly.
When you click on the map the colours shown represent the iron level compared to the Maximum Acceptable Value (MAV) of ≤ 0.3 g/m3. The colours show iron levels of:
| value less than 0.15g/m3 |
values between 0.15g/m3 & 0.3g/m3 |
value more than 0.3g/m3 |
Explore iron readings over time
The Water Scheme filter applies to the table and graph below.
Explore iron readings over time
The Water Scheme filter applies to the table and graph below.
Iron testing and frequency
The drinking water authority Taumata Arowai have published aesthetic values for New Zealand drinking water in the Aesthetic Values for Drinking Water Notice 2022.
The authority also sets a frequency of testing source depending on the population which ranges from monthly for large supplies to annually for smaller supplies.
All samples are analysed in an IANZ Accredited Laboratory. The detection threshold for iron is 0.021 g/m3. New Zealand’s water legislation sets required units as “mg/L”, which is a different way of expressing g/m3.