How is it treated?

Once the water has been collected at the intakes from the rivers, or is drawn from the aquifer, it enters a treatment plant.

There are four treatment plants around the region and they are owned by Greater Wellington Regional Council.

The Ministry of Health has established guidelines for safe drinking water: the Drinking Water Standards for New Zealand 2005 (revised 2008). Our treatment methods are designed to produce water that meets these standards and satisfies the needs of our customers.

Once the water has gone through the treatment process it is distributed along the drinking water network.

Group Tours

Wellington Water hosts a number of group tours throughout the year of the treatment plants in Wellington. If you are interested in having a group tour, please email

Te Marua water treatment plant

The water treatment plant, pumping station and storage lakes at Te Marua were built between 1980 and 1987, to treat water taken from the Hutt River at Kaitoke.   Read more

Wainuiomata water treatment plant

The Wainuiomata water treatment plant receives water from the Wainuiomata and Orongorongo rivers and three smaller creeks (Georges, Big Huia, and Little Huia). The plant's design capacity is 60 million litres per day (ML/d), but production is typically around 30 ML/d or just under 20 percent of total supply each year.   Read more

Waterloo water treatment plant

Eight wells supply water from the Waiwhetu aquifer, beneath Lower Hutt, to GWRC's Waterloo Water Treatment Plant, which was commissioned in 1981.   Read more

Gear Island water treatment plant

Gear Island water treatment plant sits beside the Hutt River at the eastern end of the Petone foreshore. The plant was commissioned in 1935 and, like Waterloo, treats water from the Waiwhetu aquifer.   Read more

Waiwhetu Aquifer - chlorination

Greater Wellington Regional Council has approved the permanent chlorination of Lower Hutt drinking water. The Council voted in favour of a recommendation from Wellington Water, based on our Waterloo Wellfield Water Quality Contamination Investigations Report.   Read more

What's in your water?

Safe and reliable drinking water is vital to the health and prosperity of our region and its people. We are responsible for making sure that the water supplied to Lower Hutt, Porirua, Upper Hutt and Wellington is clean and safe to drink.   Read more