Crews in New Jersey are assembling a pair of custom-built machines that will dig out the first new set of Hudson River train tunnels in more than a century.
Officials behind the $16 billion project, the centerpiece for the larger Gateway Program, showed off the high tech boring machines on Monday. Each one is made up of nearly a hundred pieces and when put together, will make up a 500-foot, 1,700-ton digging behemoth.
The machines highlight how far tunneling technology has come since the early 20th century, when workers for the Pennsylvania Railroad dug a set of Hudson River tunnels by hand in pressurized chambers that sickened many with the bends…