From railways to greenways: a complex index for supporting policy making and planning. A case study in Piedmont (Italy)

All over the world, a significant percentage of the railway network has been closed from the 1960s onwards. This represents a heritage that can be used to provide new features to local communities, to support sustainable development and landscape regeneration processes. Disused railways can be converted into greenways dedicated to not motorized users and people with reduced mobility. Greenways can be related both to leisure and tourism and to commuting. The growing interest and social demand for greenways can find obstacles in the scarcity of public funds. Decision-makers and land-use planners need to assess potential benefits and costs for local communities and the attractiveness for users. In this paper, we aim at providing a transferable working tool able to support decision-making and land-use planning processes related to the conversion of disused railway lines into greenways in mixed urban-rural contexts. We tested the developed methodology in Piedmont (Italy) a region with almost 600 km of abandoned railway lines and over 200 disused stations. We used Geographical Information System (GIS) to carry out spatial data analysis and analytic hierarchy process (AHP) for integrating the preferences of stakeholders. We assessed the characteristics and current conditions of the disused railways network and the territorial and social context, defining a synthetic global index (the Greenway Suitability Index - GSI), for the evaluation of the priorities. We defined four scenarios in order to verify how the priorities can change in relation to the objectives, and calculated GSI, that consider the importance of the different territorial characteristics (natural element, historical-cultural resources, traditional food and local wine, landscape/scenery, accessibility and population), in relation with specific scenarios. The successful application demonstrated that the methodology can be used to calculate a sort of “priority score” considering stakeholder’s preferences and allowing the land-use decision makers to concentrate the investments in a priority way.