High tide

25 February 2015

It’s an exciting time for the International Tunnelling Association (ITA) leadership. With growing international acceptance that climate change is affecting the world, there are two outcomes. Firstly, governments try to change the habits of the planet to slow the pace of a changing biosphere. This is a boost to the demand for tunnelling on the larger scale; governments looking for low-carbon per capita means of transportation, for example. Metro networks rather than private car ownership.

The second is an acceptance that natural disasters induced by a warming globe are likely to increase in frequency and intensity. This is a problem the ITA can really help with on a project planning level.

In a Q&A session released by the ITA and featured in this issue, President Soren Degn Eskesen looks at the role that tunnelling, and the clever use of underground infrastructure in general, has to play in protecting people and structures from disasters. There is, he says, a growing recognition that the costs of not acting (reacting) are now outweighing the costs of being prepared for such events. In the most straightforward sense, the costs of efforts to rebuild look more and more prohibitive when compared with defences.

Efforts in recent years to show the clever uses underground space can be put to are paying off, Eskesen says, as it appears the relevant UN bodies are consulting ITA more and more to learn the possibilities tunnelling has to offer in this regard. Multifunction tunnels such as Malaysia's SMART project are a good example of this, and are an efficient use of capital and space.

Eskesen references early investment in metro projects in some of the world's major cities, and the benefits enjoyed by several generations of urban populations.

He doesn't point out the enduring problems that can be caused by poor planning. On, for example, the early London Underground lines. While the benefits of infrastructure investment are felt by generation after generation, poorly planned - or just not optimal - projects can create problems for future engineers trying to solve a problem that could have been identified earlier.

A few years ago, a lot of the excitement from the ITA centred on underground master plans. Helsinki was held up as the golden example - reserving areas underground and placing current infrastructure in such a way that wastage of space could be minimised.

Unfortunately for some of the older cities with extensive networks of underground infrastructure, placing new infrastructure with maximum efficiency is impossible.

Even without strategic placement considerations, individual projects sometimes have to take a less than optimal route to avoid even defunct, small-diameter tunnels.

But for a lot of newer cities in Southeast Asia, the underground is less spoilt, and engineers have options, if they look for them.

It's lucky when you think of another of Eskesen's points: that Southeast Asia seems to be taking the brunt of the flooding.

And tunnelling can help treat the symptoms of a warming world.