Greater Wellington

Future: Greater Wellingon is considering the possibility of developing an aquifer in the Upper Hutt area. This would supplement the water supply from the existing Te Marua water treatment plant, where the supply is fluoridated. If the aquifer were developed, the water would be fluoridated.

Current situation:

Upper Hutt, ManorPark Stokes Valley and Porirua all receive water from the Te Marua Twin Lakes. This has sodiumsilicofluoride, chlorine, alum hydroxy and lime.

Wainuiomata receives water from the Wainuiomata hills and has the same additives as Twin Lakes.

Lower Hutt (excluding above suburbs) receives water from Waterloo pumping station. Lime is added to all water, but sodiumsilicofluoride only added to the channels going to suburbs other than Petone.

All Porirua city suburbs receive water from Twin Lakes.

Wellington city suburbs receive a combination of Twin Lakes, Wainuiomata and Waterloo water.  Hydrofluorosilicic acid is added at Gear Island (east end of Petone). This "treats" the waterloo water just prior to it converging with the Wainuiomata water on its way to Wellington.

Additives by treatment plant:

Waterloo: fluoride, lime (to reduce aggressiveness of water)

Wainui: lime (increase alkalinity), CO2 (control raw water pH), polyaluminiumchloride (coagulate colour and particles), polyelectrolyte (aid filtration), chlorine (disinfection), lime (reduce aggressiveness of water), fluoride ("dental health").

Back to Fluoridation agents by area.