Urenui/Onaero wastewater project

This project is to collect and pipe wastewater from the Urenui and Onaero towns and domains to a local treatment plant and then irrigate treated water to land.

Why do we need a wastewater treatment system?

Water quality testing of the Urenui River has shown there are issues with the performance of some private septic tanks, which are contaminating the surrounding environment and stormwater systems.

In addition to the water quality concerns, the wastewater flows from the domains are currently greater than our resource consent allows, the Onaero wastewater irrigation site is at risk of coastal erosion, and the Urenui wastewater irrigation site is on culturally important land.

Due to health concerns, Te Whatu Ora (Health New Zealand) has advised recreational users of Urenui River to stay off the mud flats, avoid collecting kai mātaitai/shellfish from the river and avoid swimming in the river for 72 hours after heavy rain. Ngāti Mutunga has also updated the existing rāhui on Urenui River to align with this advice.

Since 2019, NPDC has been working with Taranaki Regional Council, Ngāti Mutunga and Te Whatu Ora to help residents fix and maintain their septic tanks and managing wastewater issues at both the Onaero and Urenui campgrounds. Unfortunately, this work is unlikely to resolve the contamination issue as the towns’ septic tanks are too close together (due to property size) and the soil isn’t suitable for septic tanks.

During NPDC’s community consultation on the 2021-31 Ten-Year Plan, Ngāti Mutunga and locals made it clear that they wanted a long-term solution to the contamination of the Urenui River, which has led to NPDC approving the construction of a new wastewater treatment system.


The new wastewater treatment process

When the new system is in place:

  • Wastewater will be collected from properties and piped to a new treatment plant.
  • New treatment plant will be built to treat the wastewater.
  • The clean, disinfected water from the treatment plant will be irrigated onto land around the plant.

Click/tap on the image to enlarge.

Project updates

Late February 2024: Quarterly site progress update available here.

February 2024: We're updating NPDC's Strategic Projects Committee about the Urenui/Onaero wastewater project at its meeting on 6 March. The agenda paper will be available on our Meetings webpage around 28 February, and you can watch the meeting live via that webpage too.

December 2023: Quarterly site progress update available here.

October/November 2023: Pop-up information stands at the Urenui Market, and a flyer sent to all households in Urenui and Onaero.

February 2023: NPDC purchased 84ha site on Main North Road Onaero, as the favoured site for the project. This property was purchased because it is larger and closer to the Urenui and Onaero townships than the Waiau Road property (previously purchased), which will simplify and reduce the cost of construction and operations. Working through obtaining resource consents for the site and design. Both properties will be retained until the consenting process is completed.  

February 2023: Assessment of potentially suitable sites for the project completed.

October 2022: Urenui and Onaero Community Open Day to update residents on progress.

May 2022: NPDC buys 41ha of land on Waiau Road near Urenui and Onaero potentially for a treatment plant and irrigation site.

October 2021: Replacement of the Urenui public toilet’s septic tank.

October 2021: Urenui Community Open Day on good septic tank management.

2019: Curious Minds project with Urenui and Mimi schools, Ngāti Mutunga and Taranaki Regional Council find contamination in the Urenui River.

Join our mailing list to receive updates from us on this project

    Frequently asked questions