Auckland Council and Watercare are working together to invest in quality stormwater and wastewater services for central Auckland.
The primary goal is to ensure our waterways are healthy and sustainable over the long term, as well as providing quality waste and stormwater infrastructure for a growing Auckland.
Central Interceptor already underway
Already happening in this term of council is the construction of the Central Interceptor – a $1 billion combined stormwater/wastewater tunnel project which will carry wastewater from Western Springs to the treatment plant in Māngere.
The Central Interceptor is proposed to be completed by 2026. One significant outcome of the interceptor is it will reduce wet weather overflows by up to 80 per cent.
The interceptor will also provide additional capacity on the current wastewater network to enable continued growth in central Auckland and parts of the south.
The council has also undertaken immediate solutions in the affected area. For example, some properties will come off the combined wastewater/stormwater system through separation programmes, such as in Waterview, where 400 properties are estimated to be put onto a separated system by 2018.
Another solution is the network optimisation work being undertaken by Healthy Waters in St Marys Bay, as well as a project in Three Kings where stormwater will be separated and disposed of via soakage (in the ground).
Currently the cross-council team, made up of Watercare and the council’s Healthy Waters department supported by key external advisors, is investigating further improvement options within central Auckland catchments.
Old combined network
During wet weather, overflows within the combined stormwater/wastewater network regularly occur.
This is due to a decades-old combined network – which mainly covers 16,000 homes across central Auckland including parts of Point Chevalier, St Mary’s Bay, Remuera and Three Kings.
This combined wastewater/stormwater network is designed to discharge through outfalls, mainly into local streams. Consequently, this has an adverse impact on some central Auckland beaches.
Watercare estimates that, each year, up to 1 million cubic metres of combined stormwater and wastewater from central Auckland's combined infrastructure is being discharged through outfalls.
Committed to a solution
Both Watercare and Auckland Council are committed to significantly reducing this and want to improve the water quality in central Auckland’s receiving environments. This is why the group will report back to the council in the coming months with potential costed solutions, timings and pricing.
The findings of the cross-council group will be considered as part of the 2018 draft Long-term Plan, which will be presented to Aucklanders later this year.
Auckland residents will have an opportunity to respond to the various stormwater/wastewater options and how they will be funded.