20 November 2018
Feedback sought on plans to improve Porirua wastewater system
Community feedback is being sought on proposals to upgrade the wastewater system that serves Porirua and northern
Wellington city suburbs, to improve the health of Te Awarua-o-Porirua Harbour.
Wellington Water Principal Advisor RMA and Environment Stewart McKenzie says discharge consents for the wastewater
treatment plant will expire in 2020 and need to be renewed, and some capacity and performance upgrades to the plant are
“However, there are broader issues with the ageing wastewater network of pipes and pumping stations, including overflows
during heavy rainfall as well as dry weather leakages. These are not consented but need to be, as part of managing and
“That is why we are proposing to prioritise improvements to the wastewater network over the treatment plant, as this
will reduce overflows and leaks, and help improve the health of the harbour and coastal environment.”
Wellington Water has worked collaboratively with Porirua City Council, Ngāti Toa, Greater Wellington Regional Council,
Wellington City Council, the Whaitua Committee and other stakeholders in developing the proposed wastewater improvement
Porirua City Council Councillor Ross Leggett says improving the health of Porirua Harbour and the catchment is one of
the council’s four strategic priorities set out in the Long-term Plan.
“Te Awarua-o-Porirua Harbour is the heart of our city and community. It is taonga for Ngāti Toa Rangātira and it is one
of our community’s greatest ambitions to improve its health,” says Councillor Leggett, who is also Chair of the
Wastewater Treatment Plant and Landfill Joint Committee with Wellington City Council.
“We are already investing more in wastewater infrastructure to not only protect the harbour but ensure we have a
wastewater infrastructure that will support the ongoing healthy growth of our city and the northern Wellington city
suburbs it also serves.”
Mr McKenzie says improvements to the wastewater network being considered include continuing to upgrade pumping stations
to reduce overflows into the harbour during storms, building wastewater storage tanks to hold back the flow of water to
the treatment plant in heavy rainfall and reducing the amount of stormwater that can enter the network in heavy
Upgrades to the treatment plant would include equipment upgrades, increasing its capacity to treat up to 1,500 litres of
waste water per second following heavy rainfall and investigating new locations for the discharge from the plant.
“We are now reaching out to the community for your feedback on the approach we are proposing to improve wastewater
management in the catchment,” Mr McKenzie says.
“Over the next few months we’ll be out talking to community groups and schools and encourage people to come forward with
their views and ideas.”
Wellington Water expects to lodge an application with Greater Wellington Regional Council for the treatment plant
discharge consents in late 2019, which would be followed by a submissions and hearing process.
Wellington Water plans to lodge consent applications for network overflows, along with plans to reduce them, in 2020.