The Central Interceptor will provide many benefits.
When it rains the central wastewater network overflows to local waterways and the Waitematā Harbour at more than 100 locations and to the north-eastern Manukau Harbour at 14 locations.
The Central Interceptor is an integral part of our long-term strategy to effectively manage wastewater within Auckland. While we’re building the tunnel, we will also be working on other projects in the western isthmus, such as separating the stormwater and wastewater pipes. Together, the Central Interceptor and our western isthmus strategy will reduce overflows in the area by up to 80 per cent.
Reduce environmental risks
The existing wastewater pipeline that passes under the Manukau Harbour was built in 1964. This pipe is now reaching the end of its operational life. If the pipe is damaged or fails, untreated wastewater could be discharged into the Manukau Harbour.
When the Central Interceptor is complete it will help keep the Manukau Harbour clean. It will also significantly reduce the largest existing combined wet-weather overflows in Auckland, located at Lyon Avenue in Mt Albert and Haverstock Road in Sandringham.
Increase network flexibility
The Central Interceptor will help us provide additional capacity in central Auckland and free up capacity in the east and west of the city. This means we can take critical infrastructure out of service for maintenance without impacting our services to you.
Help a growing city
Auckland ‘s population is growing significantly. Over the next 30 years, we’ll need room for another 1 million people. The Central Interceptor is critical to providing additional wastewater capacity for our expanding population and connection of future wastewater projects.
Connecting to the western end of the Ōrākei Wastewater Interceptor, the Central Interceptor will provide a more direct route to the Māngere Wastewater Treatment Plant for much of central Auckland’s wastewater flows. This will allow greater capacity for growth in other parts of the network. The Northern Interceptor, which we started to build in 2018, will divert some of the northern wastewater flows to Rosedale Wastewater Treatment Plant, freeing up more capacity in the southern network to allow for future growth
Download the Central Interceptor brochure.