Central wastewater storage tank

A major infrastructure project for a storage tank is underway to help stop wastewater overflowing into Porirua Stream and Te Awarua-o-Porirua Harbour.

For a healthier harbour and coastal waters, we need to reduce the amount of untreated wastewater overflowing from the network. Overflows happen when wet weather increases the amount of water flowing through the network beyond the amount the pipes can carry.

To reduce overflows we're building a storage tank in central Porirua, to help stop wastewater overflowing into Porirua Stream and Te Awarua-o-Porirua Harbour.

The tank will be located north of Porirua railway station, between SH1 and the railway line (artist's impression shown above).

It will hold up to seven million litres (about three Olympic-sized swimming pools) of wastewater when there is heavy rain. Once the rain stops, the wastewater from the tank will be pumped to the Wastewater Treatment Plant in and fully treated.

The first stage of the project is an access bridge over the Kenepuru Stream to provide safe access to the site for construction and ongoing operation, from the south side of the stream within the existing park and ride facility.

For info about the project from Wellington Water click here

The access bridge over the Kenepuru Stream.

Click here for more information, maps and lots of FAQs.


Proposed location for the tank

Community questions received

The planned construction completion date is 2026.

The proposed partial-buried reinforced concrete tank has a life span of 100 years.

The NOR is permanent and the Construction Consents last for five years.

Via the Council's Long-term Plan (LTP) process. The consent process costs have been budgeted within the estimated total project cost.

Central Government removed water projects from shovel ready funding.

Business and Economic Research Limited's (BERL) projected population for 2057 of 121,800 was used to size the tank.