Taipa Wastewater Treatment Plant – Better Off Funding Project

This project is delivered under the Better Off Fund programme, a central government initiative designed to support communities as local authorities transition away from managing Three Waters infrastructure.

The Taipa Wastewater Transformation Project secured this funding to progress its core objective of removing treated wastewater discharge from the Parapara Stream and restoring the mauri of the wai for the benefit of hapū and the wider community.

We have been engaged to support the delivery of this programme, including advancing discharge to land investigations and implementing a trial of electrocoagulation as a potential treatment solution for the Taipa Wastewater Treatment Plant, and potentially other sites across the district.

The challenge

The Taipa Wastewater Treatment Plant presents a complex environmental and community issue. The existing system relies on biological pond treatment that wasn’t designed for current population demands and future growth, and currently discharges treated wastewater to the Parapara Stream.

The project involves delivering a first-of-its-kind electrocoagulation trial in a municipal wastewater treatment plant setting in New Zealand, balancing technical feasibility with evolving regulatory requirements.

Key challenges include:

• Implementing new treatment technology in an operational plant, installing and commissioning the trial without disrupting ongoing operations or consent compliance

• Establishing robust monitoring and verification methods, with reliable online monitoring and sampling to demonstrate performance improvements and provide defensible data for decision-making

• Identifying a viable alternative discharge solution, with a focus on discharge to land

• Undertaking technical investigations to confirm the feasibility of land-based disposal

• Coordinating a multi-stakeholder working group including iwi/hapū, Council, and technical advisors

• Integrating emerging national wastewater standards and regulatory guidance into project decision-making

Our approach

The project has been progressed through a collaborative, working group-led approach involving Council, iwi representatives, and technical specialists.

Hoskin have supported this process by coordinating investigation and assessment activities, managing the implementation of the electrocoagulation trial, and facilitating ongoing engagement with stakeholders and landowners.

Through this process:

• A trial of electrocoagulation has been developed and is now underway to assess treatment performance

• Discharge to land via sub-surface irrigation has continued to advance as the preferred long-term solution

The approach has maintained a strong focus on aligning technical investigations with stakeholder expectations and regulatory requirements.

Outcomes

The project has progressed a clear pathway toward improving wastewater outcomes at Taipa.

Key outcomes to date include:

• Commencement of an electrocoagulation trial, identified as a key component in assessing future treatment options

• Advancement of investigations confirming that land-based discharge is technically achievable

• Continued progress toward securing suitable land for discharge and aligning with updated environmental standards