Project summary

What we're doing

The Southern Wastewater Treatment Plant is part of a new, boundaryless approach to managing wastewater across Hamilton, Waikato, and Waipā. By focusing on the awa (river) as a whole and planning for our region’s future growth, this project puts what’s best for the river at the heart of every decision.

It’s one of five projects endorsed through the Southern Metro Wastewater Detailed Business Case (the DBC). Hamilton City Council is the lead council for this project and is working in close collaboration with iwi, mana whenua and Waikato and Waipā councils.

 

Why we're doing it

The Waikato region has seen and is forecast to continue seeing tremendous growth and development in residential, commercial, and industrial areas.

This is placing pressure on existing wastewater services at Hamilton’s only wastewater treatment facility in Pukete and creating further demand for wastewater treatment and management services in the sub-region. 

Over the past five years, Hamilton City Council, Waikato District Council, Waipā District Council, Waikato-Tainui and mana whenua have looked at the future wastewater servicing needs across the Waikato Metro area (from Taupiri in the north through to Cambridge and Te Awamutu in the South). That work has delivered an agreed servicing strategy including major investments at the Cambridge and Pukete (Hamilton) wastewater treatment plants. This has also confirmed the need for a new plant in the south of Hamilton.

By delivering a “best for river” wastewater management solution for the region, this new Plant will directly contribute to achieving the vision and objectives set out in Te Ture Whaimana o Te Awa o Waikato – the Vision and Strategy for the Waikato River.

This project recognises and provides for the unique relationship that tangata whenua have with the awa and is underpinned by a partnership approach. We’ll uphold treaty-based partnerships through ongoing collaboration, co-design and joint decision making by council and mana whenua representatives.

What has happened so far?

Focussed investigations for the new Southern Wastewater Treatment Plant started in 2022. This built on early site selection work undertaken to support the detailed business case in 2020/21. As part of this, a site selection assessment was undertaken to determine the best location for the Plant . Through this process, eight potential site options across Hamilton City, Waikato District and the Waipā District were considered, with four sites taken forward to the shortlist.  

Site selection was thorough and involved both technical and cultural investigations. Some of the key criteria included: 

  • Proximity to Hamilton airport and the Waikato River

  • Proximity to the future servicing area (south Hamilton, Tamahere and Maatangi villages, Tauwhare Paa)

  • Any existing utilities infrastructure

  • The size of the site, with a minimum requirement of 20 hectares and a desire to ensure a significant buffer between the Plant and neighbouring properties.  

  • The site topography, with flatter terrain preferred

  • The existence of waterways (as a possible discharge method)

  • Whether there are culturally significant areas or findings on a site. 

 

Through that process a preferred site was identified. The preferred site is Council-owned land at 131 Raynes Rd. It is a large site, 34 hectares, and was chosen through a process of elimination from seven other potential sites. The preferred site is in an ideal location for future development areas, is large enough to provide a significant buffer between neighbouring properties, has access to power and communication services, and good topography with no significant natural features or known archaeological sites.

What is happening now?

The timing of construction of the new Plant is not confirmed but could be expected in the next decade. What we are doing at this stage is protecting the land for future use and providing more certainty to the community as to where the Plant and its associated treated wastewater discharge will be located.   

This includes creating a concept design for the new Plant which will determine its exact location, layout and appearance and incorporating features to manage concerns such as potential odour and noise. We will also create a master plan for the whole site which will consider what we use the land surrounding the Plant for.    

Once these steps have been completed, we will be lodging a notice of requirement for a designation and the related consents under the Resource Management Act 1991. It may take up to two years for us to reach this point of lodging the notice and resource consent applications. 

 

Our project vision

Tooku awa koiora me oona pikonga he kura tangihia o te maataamuri 

The river of life, each curve more beautiful than the last 

A future where a healthy Waikato River sustains abundant life and prosperous communities who, in turn, are all responsible for restoring and protecting the health and wellbeing of the Waikato River, and all it embraces for generations to come.

This project will

  • Contribute to the restoration and protection of the health and wellbeing of the Waikato River.

  • Meet the wastewater servicing needs of future industrial and housing development in the Waikato Metro area.

  • Take an iwi partnership and tikanga-led approach to planning, delivery and operation of the Southern Wastewater Treatment Plant.

Where we're at with progress

  • Stage 1 - Completed

    2022 - 2024

    Project set up and site selection 

    Including governance, delivery structure and mana whenua representation 
  • Stage 2 - Underway

    2025-2027

    Planning and consenting 

    Including plant design, site master planning, discharge options and consenting.  
  • Stage 3 - Planning

    TBC

    Design and build 

    The timing of construction is to be determined, but will provide capacity for growth for the next 100 years. 

Engagement timeline

2020 - 2022

2020 -2022

The Southern Metro Wastewater Detailed Business Case (DBC), completed with partners Waikato Tainui, Waikato, Waipā, and Hamilton councils, identified the Southern Wastewater Treatment Plant as part of the preferred servicing strategy.

2022 - 2024

2022 - 2024

Building on the previous site selection assessment in the DBC, four locations were shortlisted with partners, including mana whenua. Ecological, cultural, archaeological, and geotechnical investigations were completed. Discharge options were evaluated, with a short list selected for further review.

 

2024

2024

Funding approved in Hamilton City Council’s 2024-2034 Long-Term Plan to progress the concept design, site master plan, designation and consenting for the project.

2025

March 2025

131 Raynes Road was formally selected as the location for the new plant in collaboration with project partners.

2025

April 2025

Beca Limited appointed as the consultant team to lead the concept design, site master plan, designation and consenting for the project.

2025

May - July 2025

An initial outreach to landowners living near the project site and to stakeholders was carried out to share information about the project.

2025

July 2025

IAWAI – Flowing Waters established and contracted to act as agent for Hamilton City Council and Waikato District Council on Major Transferred Projects including the Southern WWTP.

2025

August 2025

Ongoing conversations with mana whenua, landowners and stakeholders.

2025

November 2025

Community information sessions held on 5 and 6 November 2025 at the JetPark Hamilton Airport Hotel and Conference Centre, giving the community a chance to meet the project team, learn more about modern wastewater treatment, and the process of designing and consenting a wastewater treatment plant.

2026

Early - mid-2026

The community will have an opportunity to share their views on what the site surrounding the plant could be used for.

2026

Mid-2026

Feedback received during the consultation period will be reviewed and used to inform the design.

2026

Mid-late 2026

The concept designs for the site will be finalised and shared with the community.

2026

July 2026 process

Ownership of the project will pass to IAWAI. Hamilton City Council will continue to be involved in the project.

2027

Mid-2027

IAWAI will lodge a notice of requirement to designate the land for the future construction of the plant. Consenting and planning approvals will also be submitted.

2026 – 2027

Late-2026 – late-2027

Post-lodgment, IAWAI will continue to provide regular updates on the project.

Sign up for updates

Frequently asked questions

How is this project being managed?

We're looking at a new way of delivering water services across the Waikato Metro Area. Hamilton City Council and Waikato District Council have just approved forming a joint waters Council Controlled Organisation (CCO). From 1 July 2026, the CCO will be responsible for delivering drinking water and wastewater services. They will also manage projects including the Southern Wastewater Treatment Plant. You can find out more here.

Where will the new plant be located?

We looked at several different locations as potential sites for the new Plant in the east and south of Hamilton and around the Airport precinct. 

After assessing each site against a range of technical requirements, as well as a comprehensive cultural assessment, we have a preferred option – parcel of Council-owned land, south of the city boundary, at 131 Raynes Rd. 

Who owns the property?

You may be aware that Hamilton City Council purchased land in 2022, which is now the preferred site for the project. This land purchase was an opportunity for Council to obtain property in a strategic growth area. The property was purchased to enable broad community outcomes, with several possible uses for the land, including the Southern Wastewater Treatment Plant. In March 2025, after thorough investigations, the property was determined to be the preferred site for the plant.

What will the plant look like?

The next step in the project is to develop a concept design which will determine what the Plant looks like and what features will be included to manage concerns such as noise and odour.  

What we do know is: 

  • This won’t be your usual wastewater treatment plant – we will use a modern design with leading technology to treat wastewater, so it is as clear as drinking water. It will also look compact and most importantly, it won’t have any large smelly ponds.  
  • The site is very large, 34 hectares, and the Plant will only take up a small portion of the land which means there will be a large buffer zone between it and the surrounding properties that could be used for other activities.  
  • Mitigation measures are likely to include facilities within the Plant that remove smell, such as bio filters and scrubbers and acoustic grade building material, and noise silencers to reduce noise.  

Information on the design, layout, and how potential impacts will be managed will be shared through regular project updates as the project progresses. Sign up to receive regular updates or check the webpage for updates.

How can the community provide feedback?

We've started engaging with nearby landowners and key stakeholders on our preferred option for the site. There will be an opportunity for the wider community to have their say when we begin the process to designate the land. We’ll also ask for community feedback on other aspects of the project, including the design and layout.

Why is the project being announced now?

The concept of a new wastewater treatment plant south of the city is not new, but until recently, we haven’t had funding to progress it. We have only recently selected a preferred site after extensive investigations into a number of possible locations

Feedback

Has this page been helpful?
Thanks for your feedback.

Last updated 18 November 2025