Waikanae treatment plant upgrade

A 30-month upgrade to increase earthquake resilience and to replace aging equipment at the Waikanae Water Treatment Plant started in February 2024 after the signing on 24 November of the contract for a $22 million upgrade.

Our why

This upgrade is part of our commitment to provide safe, clean, reliable and resilient drinking water to homes and businesses. The Waikanae Water Treatment Plant provides drinking water to more than 40,000 people in Waikanae, Paraparaumu and Raumati.

The project is stage two of a planned three-staged upgrade of the Waikanae Water Treatment Plant. These works are part-funded by a $5.2 million grant from the government, and include:

• enabling works to move utilities such as telecommunications lines and stormwater pipes out of the way for excavations needed for the clarifier (completed in 2022)
• building a rapid mix tank (to mix coagulants and flocculants which bind particles in the water)
• building a new clarifier (a large tank where the bound particles bound together)
• planned renewals to replace pumps and dosing equipment which are getting towards the end of their useful life, and
• safety improvements which include constructing a new building to house chlorine tanks and dosing systems.

The works will also increase the seismic resilience of the water supply for Waikanae, Paraparaumu and Raumati. The two-and-a-half-year project follows enabling works completed in 2022, which included relocating a stormwater line and other utilities to make way for the new equipment.

Latest news

8 April 2025 -The new 2,500 cubic metre clarifier tank at the Waikanae Water Treatment Plant was recently put through its paces to check for leaks.  After a week of measuring any drop in water (taking into account rain and evaporation), the tank was assessed as performing within specification. This allowed the team to move onto the next stage of construction involving installing the tank’s mechanical scraping equipment. 

Clarifiers remove particles from the raw river water. The river water is combined with additives, then flows into the clarifier where impurities clump together and settle to the bottom of the tank before being scraped away. 

9 April 2024 – After four weeks of earthworks, we’ve almost completed excavating for the new clarifier (a large tank which helps remove tiny particles from the river water).

We’re also using some of the earth from the hole to help build the new access onto Reikorangi Road. Please take care travelling on Reikorangi Road while the new accessway is being built.

We’re carrying out this upgrade of the water treatment plant to increase its earthquake resilience and replace aging equipment. The Waikanae Water Treatment Plant provides water for more than 40,000 people in Waikanae, Paraparaumu and Raumati.

If you live in Reikorangi or travel that way, please take extra care over the next few months while our crew carries out this important work.

Stages