Watercare operates twenty water treatment plants supplying drinking water to the Auckland region. To meet the New Zealand Drinking Water Standards 2005 (revised 2008), most raw water need to be treated. The treatment process removes suspended solids, turbidity (dirt particles) and harmful microbiological organisms. The exact level of treatment required depends on the source of the water.
Plant |
Source |
Treatment |
Capacity in litres per day |
Muriwai |
Groundwater – spring |
Cartridge filtration, pH control, chlorination, UV disinfection |
480,000 |
Hamiltons Road (Algies Bay/Snells Beach) |
Groundwater – bore |
pH control, chlorination |
1,800,000 |
Wellsford |
Hoteo River |
Sedimentation, sand filtration, pH control, chlorination |
1,440,000 |
Warkworth |
Mahurangi River |
Coagulation, clarification, PAC dosing (optional), sand filtration, pH control, chlorination |
2,800,000 |
Helensville |
Mangakura Stream
Dams and sandhills
Spring fed wetland on Ohirangi Stream |
Coagulation, clarification, PAC dosing (optional), sand filtration, pH control, chlorination |
1,000,000 |
Pukekohe |
Groundwater, 2 bores, 1 spring |
Bag filtration, chlorination |
5,630,000 |
Clarks Beach |
Groundwater – bore |
Chlorination |
154,000 |
Waiuku |
Groundwater – 3 bores |
Chlorination |
1,933,000 |
Patumohe |
Groundwater – bore |
Chlorination |
161,000 |
Puni |
Groundwater – bore |
Chlorination |
34,000 |
Bombay |
Groundwater – spring |
Cartridge filtration, pH correction, chlorination |
157,000 |
Buckland |
Groundwater – bore |
Chlorination |
164,000 |
Glenbrook Beach |
Groundwater – bore |
Chlorination |
59,000 |
Waiau Beach |
Groundwater – bore |
Chlorination |
170,000 |