Alice, one of world's largest tunnel boring machines, has started its second tunnel drive for the Waterview Connection project in Auckland, New Zealand.
The 90m-long, 3100tonne tunnel borer completed the first twin tunnel, at 2.4km, in September after 11 months of digging, as World Highways reported at the time. The machine has a boring diameter of 14.46m and its cutting wheel is driven by 24 electric motors with a total output of 8,400kW.