Cleaner, safer water through world-class treatment facilities
Watercare operates 21 water treatment plants supplying drinking water to the Auckland region. Each plant takes untreated water, also known as raw water, and removes unsafe contaminants such as suspended solids, bacteria, algae, minerals, and man-made chemicals pollutants. The end result is high quality water that is completely safe to drink.
Why does our water need treatment?
There is no such thing as naturally pure water. All water contains contaminants of one form or another. Water from the dams in the Hunua and Waitakere ranges is generally of a good original quality because there is almost no human, industrial or agricultural activity in those areas, therefore it requires less treatment than water from the Waikato River. Groundwater sources such as boreholes, springs, and wells normally only need chlorination because the raw water is already of a good standard.
How is water clarity measured?
Water clarity is measured in units of turbidity, or nephelometric turbidity units (ntu). This measurement indicates the level of dirt particles within the water. Raw water coming into the treatment plants from the Hunua and Waitakere ranges dams is exceptionally clean at around 2-5 ntu. Raw water from the Waikato River has a higher turbidity of around 20-40 ntu. However, the modern and highly sophisticated four-stage Waikato Water Treatment Plant means that the treated water is as clean as water supplied from the other treatment plants.
Different sources, different treatment processes
Because Auckland’s water comes from such a wide range of sources, there is also a wide variety of water treatment processes in use. Each treatment plant is designed to deal with the characteristics of the raw water from its sources.