Impact of new tunnels on those from the industrial era in Spain

Tunnels have been constructed in Spain since Roman times, when they were constructed for both mining and water transmission purposes. Those tunnels were bored using the available tools for soils and soft rocks and with mining methods for hard rocks: the ‘fire setting’ technique and wooden wedges soaked with water to split the rock. Further tunnelling took place in the middle ages, but the advent of the nineteenth century industrial age heralded increased activity – for example, for railway network expansion, often mining related. These tunnels signal an important heritage, which must be protected through legislation and environmental awareness. Current plans for network expansion, in particular for the Asturias region, require appreciation and sensible protection of these old, mature tunnels right across the whole spectrum of the development process. This paper presents five different types of examples in which the presence of old tunnels has had an important impact on the solution chosen for further tunnelling with or without rehabilitation or reuse of an existing tunnel, and stresses how these solutions are or should be presented publicly.