Meeting - 15 July 2024

Guest Speakers: Karen Melville & Peter Wilson

Topic: The Central Interceptor

The Central Interceptor is a wastewater infrastructure project in Auckland undertaken by Watercare Services and involves boring a 4.5 metres (15 ft) diameter wastewater pipe underneath the Auckland central isthmus, to carry wastewater flows from many parts of the city to the Mangere Wastewater Treatment Plant. The project allows for population growth in Auckland and the resulting increased wastewater demands. It also aims to reduce the amount of wastewater overflows from the older combined wastewater/stormwater systems in western Auckland, which currently, on strong rainfall days, are forced to dump excess water (contaminated by faeces) into the Waitemata Harbour. One typical example was on 27 January 2023, when a water quality alert was issued for 11 Auckland beaches because of wastewater overflows in heavy rain. The new capacity of the central interceptor is expected to reduce these overflows by at least 80%, reducing the times per year contaminated stormwater is dumped into the harbour from 52 days a year to 10 or fewer days.A major pump station, plus 16 access shafts, up to 78 metres (256ft) deep, will be constructed.                                                                                                                                                                                                                                                                                                                                                                        The new interceptor will be New Zealand's largest ever wastewater project, costing approximately $1.5B, 13 km long plus 4.3km of link sewers running from Western Springs to Mangere. In 2021 consent was granted to extend the project to Tawariki St, Grey Lynn - enabling the new tunnel to connect to the Orakei Sewer Main. In May 2024, resource consent was granted to extend the tunnel further to Point Erin Reserve - giving the project a final length of 16.2 km.

Our presenters to tell us all about this project are:

Karen Melville, who is the Stakeholder and Communications Manager for Ghella Abergeldie JV (GAJV) the contractor constructing the Central Interceptor. Her team looks after the various stakeholders impacted by the project. She’s been with the JV for more than four years and previously worked for Aurora Energy, an electricity distribution company in Dunedin.

Peter Wilson, who is Stakeholder and Communications Lead for Watercare, dedicated to the CI project for the past four-and-a-half years. He sets the stakeholder strategy, promotes the benefits of the project via a range of communications media and manages relationships with local politicians.

This is an excellent presentation of a major project that we know very little about. You will be enthrtalled with the scope of the project and the outcomes to the benefit of Auckland Central City. So bring your partner and/or a guest to be equally entertained by this presentation!