Yet that doesn’t equate to perpetual workload and revenue. The current economic challenges for clients, in the UK and internationally, can bring a squeeze, such as of late.

Projects are happening though, including major ones continuing and achieving key milestones with breakthroughs and completions of excavations, or preparing for tunnel bores to begin.

Those are all business challenges. What factors never goes away are the technical challenges. How could they – geology is forever variable, both a marvel and headache.

Entrancing. Enough so to distract – almost – from economic swings and roundabouts. But never totally, for how the engineering is approached and undertaken can bring comfort or otherwise to projects, in some cases. Tunnelling projects are, indeed, tough challenges.

But so much is achieved and there is much work, and so let’s look at some upsides.

In this issue we have features that discuss how surveying technology help a contractor move quickly on a rock tunnelling project in Norway; on other projects, the ability of tight-turning technology for TBMs helps to expand sewer networks in congested Mumbai; the drive for more sustainability has lower carbon concrete linings being pursued; multiple tunnelling methods get employed in Vienna for metro expansion; and, a delicate part of the Pacific Northwest coastline is left untroubled by using trenchless systems for wave energy R&D; and more.

There is, indeed so much happening – and to come, as we spotlight with a pipeline of projects in the Americas, thanks to analysis by T&T’s sister publication GlobalData. Much to talk about, such as at NAT 2024, in Nashville, in June.

And, there is so much that has happened, giving much to celebrate on the challenges of the past that were met and overcome, as is noted in ITA’s list of iconic projects of the last 50 years, which we review.