Boston’s Jacked Tunnels Solve Interchange Challenge

The Central Artery in Boston, Massachusetts, known locally as the ‘Big Dig’, is a landmark project in urban infrastructure redevelopment. It was vital to minimise the disruption during construction. The tunnel jacking, which provided a key solution to this need, is by far the largest and most complex project of its kind in the world. Well over ten times the size of any jacked tunnels attempted in the USA before, it has involved a wide range of innovation. The tunnel jacking has delivered a low maintenance, robust construction while bringing important environmental benefits and contributed to over US$300 million in construction savings. The project has strongly demonstrated that, for particular spatial and operational constraints, tunnel jacking can provide the best overall value and performance in creating new infrastructure.