Projects / Waterloo Water Treatment Plant Upgrade

Waterloo Water Treatment Plant Upgrade

Current status

On behalf of Greater Wellington Regional Council, we are upgrading the Waterloo Water Treatment Plant to increase the resilience of this critical infrastructure that supplies safe drinking water to the Hutt and parts of Wellington City.

Start Date
End Date

If you have any questions about this work, please contact:

Wellington Water, 04 912 4400

Work commenced on the upgrades early March 2023 and is expected to take around four months to complete.

Because the work is being done within the treatment plant compound, there will not be any impacts on trains, traffic or commuter parking.


Why are we doing this?

The Waterloo Treatment Plant located next to the Waterloo Railway Station is an important part of the Wellington region’s drinking water infrastructure, delivering 40% of the Wellington urban region’s water supply.

The purpose of the project is to increase the plant’s on-site chemical storage capacity, seismic resilience and install new systems to protect the health and safety of crews, the environment and community.

The project is part of our ongoing programme to improve the resilience of the drinking water network in the Hutt Valley that serves the wider region.

Find out more about the Waterloo Water Treatment Plant, the region's other water treatment plants and how water is safely delivered to you, here 

What are we doing?

The upgrades include:

  • Installing two seismically resilient storage tanks inside the plant buildings, significantly increasing capacity to safely store water treatment substances on site and reducing the need for frequent deliveries. The tanks will be installed in a reinforced and fire-proofed room, further enhancing health and safety outcomes and protecting the environment and community in the case of a major earthquake or event.
  • Providing a new access system for delivery of water treatment substances and a new automated system for dosing.


The work is all being done inside the plant building within the existing compound and will not disrupt the community or affect train services.

While there will be some minor loss of parking at the northern end of the station for site access, this will not affect commuter parking.