Work on the Pahiatua Wastewater Treatment Plant (WWTP) upgrade and wetlands project is progressing well, with key construction milestones now in sight and completion on track for September.

Council representatives were on site last week alongside project partners and stakeholders, including Ngāti Kahungunu ki Tāmaki nui-a-Rua, Rangitāne o Tamaki Nui-ā-Rua, Horizons Regional Council and Enviroden to review progress and upcoming works.

Earthworks for the constructed wetlands, which will improve the quality of treated water before it’s discharged into the environment, are now approximately 80 percent complete, with final construction works underway. Native planting is scheduled to begin in May, marking an important step in establishing the wetlands that will play a key role in improving water quality and supporting biodiversity.

Construction of the Dissolved Air Flotation (DAF) plant, which will improve how solids and nutrients are removed from wastewater before it enters the wetland for further treatment, is also advancing, with foundations and associated infrastructure around 75 percent complete. Most of the essential equipment for the DAF system has been fabricated, shipped, or is ready for installation. The next phase will see installation of the DAF unit, along with associated chemical dosing and holding tanks.

The project is being delivered through a strong network of mostly local contractors and iwi partners, highlighting the value of local expertise and collaboration.

Horizons Regional Council is providing regulatory oversight, while Ngāti Kahungunu ki Tāmaki nui-a-Rua and Rangitāne o Tamaki Nui-ā-Rua are contributing cultural guidance and supporting environmental outcomes through their role as kaitiaki.

Technical design for the wetlands has been led by Tonkin & Taylor, with Enviroden responsible for the engineering and fabrication of the DAF treatment system. Earthworks for the wetlands are being undertaken by HES, while Think Water is delivering the irrigation link between the DAF system and wetlands.

A number of local subcontractors are also contributing to delivery of the project, including Morris & Bailey (concrete works and foundations), Turtons Farm Supplies (pole shed construction), Jake Fletcher Contracting and Dirtworx (earthworks for the DAF).

Tararua District Council Group Manager – Operations, Hamish Featonby says the project demonstrates the strength of local partnerships in delivering critical infrastructure upgrades.

“This project is a great example of local knowledge, expertise and collaboration coming together to deliver improved environmental outcomes for our community.

By working closely with iwi, contractors and technical partners, we’re ensuring the upgraded plant not only meets regulatory requirements, but also supports the long-term health of our waterways.”

Once complete, the upgraded wastewater treatment system and constructed wetlands will improve the quality of treated wastewater, helping to reduce nutrients and contaminants entering the environment.

More information about the project is available here: Pahiatua Wastewater Treatment Plant Upgrade and Wetlands | Tararua District Council