Shutdown of the main outfall pipeline to Pencarrow (up to 6 weeks)

A shutdown of the main outfall pipeline that carries fully treated wastewater from the Seaview Wastewater Treatment Plant to Pencarrow will be in place for up to six weeks from Monday 25 May 2026.

The shutdown is for a planned programme of maintenance on the pipe, pump stations, and related machinery and installations, to support resilience and operation of the pipeline.

The maintenance is being conducted in accordance with our resource consent with the Greater Wellington Regional Council.

For the shutdown and works to occur, the pipeline needs to be emptied. This will involve discharging fully treated wastewater from the main outfall pipe from scour valves along the coast for a period up to five days from 25 May.

To keep the pipe empty for the duration of the maintenance works requiring the pipeline to be empty, fully treated wastewater will also be discharged to the Waiwhetū Stream. There will also be limited discharges of groundwater from at least one scour valve along the coast while the pipeline is empty.

There will be public signage at each discharge location. While there are no expected health, environmental, or odour risks associated with these works, people are advised to please read the signage and refrain from gathering kaimoana and swimming at the points of discharge.

Our crews will be working at different locations along the pipeline concurrently to advance this work as quickly as possible, which includes:

• inspecting the pipe and fixing leaks if required
• replacing parts at scour valves along the pipeline
• mechanical parts renewals and maintenance at the pump station and vortex installations at Pencarrow Head
• general maintenance along the pipeline, for example at culverts and to manholes.

For more detail on the maintenance plan, visit our website at Seaview Wastewater Treatment Plant.

There will be some traffic management in place for some of the works. We appreciate the impact of traffic management arrangements on the community and are working with Hutt City Council to finalise a plan to reduce the impact on you.  We will provide more information on dates and locations closer to the works starting.

Thank you for your patience while this important work is completed.

We will provider regular updates as this work progresses, including on our Facebook page.