The excavation of this part was started on 19 April 2021, when the construction had been started almost one month ago. The construction activities were commenced beneath the Isarco river for the future Brenner Base Tunnel railway. Excavation under the river was only possible after freezing the soil with liquid nitrogen and then maintaining low temperatures by circulating brine.
The digging process was done using a percussion hammer that has meanly 1.5 m advancement per day. The next phase of the work after finishing the excavation stage will be the final concrete lining of the tunnel. By utilizing the soil consolidation method one of the other tunnels was broke through during 2020, while two other tunnels are yet to be dug using the same method. Click here for tunnelingworld archive and also visit this website for more information.