What's in your water
Water naturally contains a variety of chemical elements, which it absorbs from the land that it flows over and through. In addition, we use aluminium (for treating river water) and lime during the water treatment process. Fluoride is added following treatment to provide dental protection. Although the concentrations of elements in water are very small, some have the potential to cause health problems if consumed at higher than recommended levels over many years.
The Ministry of Health's (MoH) Drinking Water Standards for New Zealand (DWSNZ) lists recommended maximum safe concentrations of all chemical elements present in New Zealand water supplies that are known to be potentially harmful. Our water treatment processes are designed to provide water with much lower concentrations of these chemical elements than the Standards allow.
The mean values of chemical analysis at each of our four water treatment plants for last full operating year can be viewed by selecting the appropriate link from the left-hand navigation bar on this page. Values are compared with the maximum allowable value (MAV) for that element as contained in the DWSNZ.