Pahiatua Water Treatment Plant

The Pahiatua Water Treatment Plant is a new plant that takes water from the Pahiatua bore and the Mangatainoka River and treats it to produce water that is better than NZ Drinking Water Standards. It does this with Ultra Fine (UF) membranes and advanced oxidising ultraviolet (UV) technology that can remove impurities and deal to taste and odour issues that are present in the water.

Benefits of the new plant:

  1. Treating turbidity and improving security of supply:The new plant will be able to treat the high levels of turbidity (cloudiness or haziness) in the water from the river. Previously, the water take from the river has been cut off during periods of very high turbidity and Council has had to rely on the supply in the Pahiatua bore. The new plant, coupled with the new 6,000 cubic metre reservoir, provides Pahiatua with a reliable source of drinking-water well into the future.
  2. Making considered and future-proof decisions: The plant is located next to the existing water treatment plant and adjacent from the wastewater treatment plant. It has been designed to limit the noise produced by the plant and minimise noise for any neighbouring properties. The plant has allowed space for future developments with room for more UF membranes should the population grow (therefore increasing demand).
  3. Utilising technology: The plant has been designed so that it can be operated remotely and only requires staff to visit for scheduled maintenance or to receive a delivery of chemicals for chlorination and cleaning will every 4-6 weeks.


The Pahiatua Water Treatment Plant was completed on 18 September 2020 with the Rt Hon Jacinda Ardern Prime Minister of New Zealand, joining us for this significant milestone for the Pahiatua community.

Although wet and windy, the opening of the Pahiatua Water Treatment Plant was a great success. We would like to extend a thank you to Tama Tu Tama Ora who welcomed everyone with their beautiful waiata. You set the tone for a great celebration.

A formal blessing will be completed by local iwi once the new pipes have been commissioned and are ready to pump up to the 6000m3 steel reservoir visible above the township.
Everyone involved in this project has worked hard to deliver a great outcome for the Pahiatua Community. We look forward to it being operational very shortly.