Industries have been increasingly engaging with calls for more sustainability in their performance, including those requiring major civil engineering infrastructure such as tunnels. The long-term ownership of tunnels brings questions around their design, construction and operation from the perspective of sustainability.

So, too, comes the question of whether new build is always, necessarily, the option to choose. Perhaps a different choice will come into the frame when sustainability is considered in its widest perspective. The possibility must be held.

But underground assets that exist already also need to be considered, including whether such tunnels are robust enough to deal with anticipated changes to climactic patterns – in addition to basic refurbishment requirements. Upgrade and expansion may, at times, be the way to go.

Suitable methods of measurement need to be settled to be most appropriate to tunnelling and straightforward to execute. The metrics of sustainability need to be practical but they are not enough. Equally important for delivery, and building momentum, is how clients and industry can work together, the extra options that could help them do so.

Confrontational relationships and lowest financial cost bid awards are unlikely, at scale, to deliver sufficient change. Options may include some new approaches in contract law and procurement to reduce friction, quicken results and undertake more projects.

Many such points on sustainability in tunnelling are covered in this issue of T&T, including in our WTC 2022 preview special which includes contributions from ITA presidential nominee Prof Arnold Dix and also Dr Alun Thomas, Antonia Cornaro and Han Admiraal.

Recognition of the practical challenges ahead along with a shared desire to deliver change are necessary – and the leadership to do so. There is much to discuss at WTC 2022, in Denmark, and in national tunnelling societies.

Patrick Reynolds Editor