The TBM that will be used for the excavation of the Central Interceptor Project has officially been ordered. The Central Interceptor is New Zealand’s largest ever wastewater tunnel, that will run between Western Springs and the Mangere Wastewater Treatment Plant.

The tunnel will be excavated with a 5.45m diameter Earth Pressure Balanced Tunnel Boring Machine (EPB TBM) provided by Herrenknecht.

The TBM will be tunnelling underneath Auckland, at depths between 15 and 110 meters underground. The internal diameter of the tunnel will be 4.5 meters, high enough to fit a giraffe.

The project includes also the construction of two long pipe-jacked sewers, at depths ranging from 12m to 70m. There will also be 16 permanent shafts, between 3m to 12m internal diameters at depths of 12m to 80m. These will be  for operational use and in the future they will collect and transfer wastewater from the existing network into the tunnel providing a more direct route to the Mangere Wastewater.

Tunnelling will start at Mangere in 2021. For further information please click here, here and nz/18 for the tunnelbuilder archive and also visit https://www.watercare.co.nz/About-us/Central-interceptor. 45/19.