The biggest Tunnel Boring Machines ever to be used in Australasia and the 10th biggest in the world will soon go to New Zealand to help build Auckland’s Waterview Connection.
The 14-metre diameter mega machine will dig two 2.4 kilometre tunnels over a period of two years, going as deep as 45 metres underground, to connect State Highways 16 and 20 and finish a motorway ring route around the city.
At 14.5 metres, the TBM’s shield or head diameter’s total length is 97m. The 12-metre long shield will go to New Zealand in eight pieces, with total weight of 2300 tonnes. It will have a top speed of 80mm per minute or 0.0005km/h.
Around 800,000 cubic metres of earth will be removed from both tunnels. That’s enough to fill 320 Olympic-sized swimming pools.
Auckland’s primary school children were asked to name the TBM and from over 500 entries, the project team chose four finalists.
The names are Soteria, Alice, Tara and Ngawini. According to the student who chose it, Soteria is the Greek goddess of safety and delivery without harm. The student chose the name in the hope that the tunnel will be completed without harming workers.
Tara was chosen as it is short for Tarawa, which is Maori for earthworm. According to the student, the TBM is like an earthworm burrowing through the ground.