Presently, the densification of disused railway areas is an important issue in the development of sustainable urban zones. The symbiotic relationship between efficient railway networks and targeted densification interventions around train stations illustrates the valuable concept of promoting sustainable development by limiting automobile use. In Switzerland, these areas offer high potential for increased urban growth, due to their context of excellent centrality and accessibility. Their development is therefore considered an attractive alternative to urban sprawl. However, the transformation of disused railway areas is not habitual, caused by numerous resistances, notably concerning their inhospitable environment and, consequently, its negative perception.
This research is aimed to highlight the optimal conditions necessary for the development of disused railway areas in urban zones. Initially, three postulates were made to help direct the elaboration of urban projects within disused railway areas, despite their specificities: optimization of train stations and their respective flows, maximum qualitative densification and functional and social diversity.
In order to adequately study this issue, a detailed analysis of disused railway areas was executed. Thanks to a strong collaboration between the research team and SBB Real Estate, second largest land owner in Switzerland, the first phase consisted of critically evaluating the SBB portfolio. Completed in 2004, this document classifies all land which is currently not used, or will not be used in the near future for railway activities. The development strategy of SBB Real Estate is also defined, particularly the criteria of evaluating the overall inventory and the applicable urban planning processes for preferred sites.
Based on this inventory, the team focused its attention on the Geneva – St. Gallen railway line as a representative sample for the entire network. The railway line extends over the country from Lake Léman in the South-West to Lake Constance in the North-East, crossing many major cities and other rural zones. This includes the Swiss Plateau, a densely populated region with a high concentration of economic growth and cultural activities. To evaluate the development potential and future obstacles, a sample of 30 disused railway areas was selected, depicted, analyzed, and portrayed using a methodology that incorporated architectural, urban, and sociological approaches.
The results of the previous phase illustrated the importance of each site’s specificity, complicating the possibility of establishing “global guidelines” and reinforcing the idea of specialized interventions for each particular case. The principal resistances against densification were also identified and analyzed, such as the site’s inhospitable environment, negative perception, slow processes of urban project elaboration, weak coordination between land owners, relocation of active railway activities, land contamination, normalization restrictions… In light of these findings, the team reoriented the research and principally focused on the process of an urban project, a major factor in ensuring the sustainable urban development of these areas.
In order to specifically understand the mechanisms and particular issues within these processes, the team examined several case studies of urban projects on disused railway areas with different progress phases, ranging from completed projects (Zurich-West, Chur) to projects currently being built (Zurich Stadtraum-HB), planned (Lausanne-Malley), or conceived (Fribourg). The five
A final analysis generated two general recommendations. The first outlined the necessity to adapt the processes to the site’s specificity, notably through the use of a flexible managerial structure. The second recommendation focused on implementing measures to initiate, rather than normalize, disused railway areas in order to improve their attractiveness, such as the modification of federal ordinances, increase of land use indicators, and financial instruments. More specifically, the research established twelve principals that can be used against resistances as a toolbox for the SBB, decision-makers, architects, urban planners, and private land owners.