Manganese
Drinking Water Quality Testing - Manganese
Manganese is a naturally occurring mineral that is found in rocks and soil.
This page shows the Selwyn District Council's testing results for manganese for water sources used for drinking water measured in g/m3.
Taumata Arowai, the drinking water regulator, is responsible for setting the New Zealand Drinking Water Standards, which specify the maximum amount of different chemicals, including manganese, that are safe to have in our drinking water. This is known as the Maximum Acceptable Value (MAV). In most cases the limits are based ont he level of risk from a lifetime of drinking the water.
Select a scheme boundary to find the most recent manganese result for each source. Data is updated monthly.
When you click on the map the colours shown represent the manganese level compared to the Maximum Acceptable Value (MAV) of 11.3 g/m3. The colours show manganese levels of:
| value less than 0.2g/m3 |
values between 0.2g/m3 & 0.4g/m3 |
value more than 0.4g/m3 |
Explore manganese readings over time
The Water Scheme filter applies to the table and graph below.
Explore manganese readings over time
The Water Scheme filter applies to the table and graph below.
Total hardness 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.
All samples are analysed in an IANZ Accredited Laboratory. The detection threshold for total hardness is 1.0 g/m3 as CaCO3. New Zealand's water legislation sets required units as "mg/L", which is a different way of expressing g/m3.
There is no mandatory frequency for testing the total hardness of drinking water. Selwyn tests annually.