A typical analysis of the chemical makeup of Christchurch water, prior to temporary chlorination.
There are 38 routine chemical tests carried out on Christchurch water with 22 of these tests establishing the presence of specific chemicals and to measure they are below acceptable limits.
| Chemical | Measure |
|---|---|
| pH | 7.8 |
| pH after aeration | 8.2 |
| Acidity to pH 8.3 (as CO3) | 1 g/m³ |
| Total alkalinity to pH 4.5 as HCO3 | 52 g/m³ |
| Turbidity (NTU) | Less than 1 |
| Nitrate Nitrogen | 1 g/m³ |
| Sulphate | 5.0 g/m³ |
| Chloride | 5.0 g/m³ |
| Calcium | 12.0 g/m³ |
| Fluoride | Less than 0.1 g/m³ |
| Magnesium | 1.5 g/m³ |
| Potassium | 1 g/m³ |
| Sodium | 6.1 g/m³ |
| Reactive silica (as SO2) | 16.0 g/m³ |
| Total hardness (as CaCO3) | 45 g/m³ |
| Conductivity at 20°C (mS/m) | 10 |
Note: Grams per cubic metre (g/m³) is equivalent to milligrams per litre (mg/l).
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