Once the water has been collected at the intakes, it is treated and distributed to the residents of South Wairarapa. All drinking water supplied to South Wairarapa is now treated using UV and Chlorine, and some treatment plants also include pH correction and Ozone treatment.

There are four treatment plants in South Wairarapa (Waiohine, Memorial Park, Martinborough, and Pirinoa) and they are owned by South Wairarapa District Council. A fifth treatment plant, the Martinborough manganese reduction plant, is currently at construction stage and will work in conjunction with the Martinborough UV plant.

Waiohine water treatment plant

The water treatment plant was built in 2018. The plant has a design capacity of up to 5.2 million litres daily (ML/d), but typically treats around 2.2 ML/d on average.   Read more

Memorial Park water treatment plant

The water treatment plant was built in 2005 to supplement the supply to Greytown from the Waiohine treatment plant. It has a design capacity of up to 2.7 million litres daily (ML/d), but typically treats around 1.5 ML/d on average.   Read more

Martinborough water treatment plant

Martinborough water treatment plant was built in 2011. Water supplied to Martinborough is extracted from bores at Herricks Wells. The plant has a design capacity of up to 4.3 million litres daily (ML/d), but typically treats around 1.2 ML/d on average.   Read more

Manganese reduction plant

We are building a manganese reduction plant to improve the quality of Martinborough’s water by removing excess manganese and iron from the water. This will allow permanent chlorination of the Martinborough town water supply. The current chlorination arrangements are temporary because the town is being supplied by only one bore, the one with the lowest levels of manganese.   Read more

Pirinoa water treatment plant

The water treatment plant was built in 1995. The plant has a design capacity of up to 28,000 litres daily, but typically treats around 10,000 litres on average.   Read more