In the Summer, the North American Tunneling (NAT) conference, held in Philadelphia, heard a number of presentations that discuss digitalization experiences. Conversations and information sharing continues in almost every tunneling forum in the region and internationally, and the next to do so is the Tunnelling Association of Canada’s (TAC 2022) annual conference, in Vancouver in November, which we preview.

Further on digitalization, we review the International Tunnelling and Underground Space Association’s (ITA) latest guide, focused on building information modelling (BIM). The guide was launched at the World Tunnel Congress (WTC), this year held in Denmark,

WTC also heard a number of presentations around sustainability – another theme of growing importance at industry gatherings, and to be a focus at TAC 2022. WTC was also the occasion where Prof Arnold Dix was elected as President of ITA and he brings an action-oriented agenda to create new measurement tools for sustainability in tunneling and a different approach to contract law, which outlines in an article inside.

The issue looks also at traditional ways of sharing lessons across sectors, such as offered by hydropower caverns for planning underground storage of oil & gas, which is of increasing strategic importance.

Keeping to caverns, a report discusses sequential excavation of a large cavern for LA metro.

Voids of a different sort, and undesired, are discussed on overcoming tunnelling challenges for TBM work in karstic limestone in St Louis.

Features on shafts for sewers and about shallow underpasses, respectively, add to the range of interesting tunneling infrastructure works covered in the issue.

Patrick Reynolds Editor