Advancing tunnelling: recognising a UK engineering legacy

Between 1760 and 1820, the Georgians pioneered modern tunnelling, constructing 47 tunnels for canals across the UK. In 1789, the then longest canal tunnel in the UK was completed after 5 years and 4 months of construction; at 3490 m, the Sapperton tunnel conveyed the Thames and Severn Canal. But there were many failures, often involving loss of life; from these, as much as from the successes, tunnelling techniques and skills were developed. The mastery of tunnelling techniques for safely traversing through the earth remains challenging for civil engineers. Since 1965, there have been over 100 reported tunnel failures across the world. While Georgian historic structures are familiar on the skylines of today’s cities, a further hidden legacy can also be discovered from the past of collective engineering experiences. This paper reviews the causes of tunnelling success and failures, bequeathed to civil engineers by their Georgian predecessors, and seeks to derive lessons for today’s civil engineers.