Besides, they can't support the wet ground, so the tunnel walls are collapsing! TBMs work much better in rock tunnels. Try this technique in a rock tunnel to find out why!

The cutter head carves a smooth round hole through the rock -- the exact shape of a tunnel. Conveyor belts carry the rock shavings through the TBM and out the back of the machine to a dumpster.

The tunnel’s entrances, designed by Snøhetta, will feature rough-hewn rock walls, walkways, and a road bridge to blend with the natural landscape and provide scenic viewpoints, potentially ...