The impact of the Vallvidrera Tunnel and Motorway on the territory: an example of applied geography

Abstract

This subject of research carried out by the Barcelona Institute of Metropolitan Studies involved the valuation of the expected impact of the construction of the Vallvidrera tunnel, the consequent motorway extension to Terrassa, connecting roads to the existing Barcelona city network and the basic road network between towns in the West Valles region. The obstacle to be overcome is the Serra de Collserola, which forms part of the Catalan coastal mountain chain. This has long been considered a barrier to the expansion of the formation of an extensive green belt, considered the most important park in the Barcelona Metropolitan Area. In this article two basic aspects are considered: (1) the role which this new infrastructure will play in Catalonia's basic road network, and (2) its direct and indirect impact on the surrounding physical environment. One fact clearly demonstrated by the study is the need to improve access within the Barcelona Metropolitan Area in the south-western part of the Serra de Collserola, and that the construction of a tunnel and some form of rapid transport might therefore be advisible. However, control of the impact on the physical environment i equally essential, bearing in mind above all the number of vehicles involved. Vehicle fume ejection combined with the unique atmospheric conditions of the zone could generate irreversible damaging effects such as acid precipitation. The principal limitation is the volume of transport-daily traffic which exceeded 20. 000 vehicles could cause more negative than positive effects. This study recommends, as a solution, the improvement of public transport between Barcelona and the Valles region, in order to dissuade the use of private transport beyond present limits.