Transport Infrastructures and Acceptability: the Role of Economic Evaluation for Conflict Mitigation

  • Silvia Maffii TRT Trasporti e Territorio
  • Riccardo Parolin TRT Trasporti e Territorio


Large and medium-size transport infrastructure shall increasingly cope with acceptability-related problems. This is due to the lack of confidence that nowadays characterises the relations between public administrations and their citizens, as well as between citizens and the project promoters. Moreover, the subjects that take advantage from the project implementation and those not often do not coincide, whereas the latter are not compensated for the damages they bear.
A sound cost-benefit analysis supporting the entire decision-making process may be a valuable tool for fostering the dialogue with all concerned subjects, provided that a set of basic conditions is met. Firstly, cost-benefit analysis has to be credible as far as the effects generated by the project are concerned. Therefore, it shall: (i) secure transparency of: results achieved by the evaluation (including the assumptions and criteria that led to such results), and procedures embedded into the evaluation process; (ii) be performed by independent evaluators rather than those sponsoring the project; (iii) be as much robust as possible, and finally (iv) deliver structured and thorough risk analyses. In order to reinforce credibility and soundness of the analysis and the evaluations undertaken, previous project experiences shall be duly taken into account, which implies fine-tuning ex-ante evaluations upon the basis of the results obtained by ex-post analysis of projects already implemented. Additionally, the evaluation shall be dynamic, as it shall back since the very beginning the whole process of infrastructure designing, and until the project is finalised. Transparency of such process is then a key pre-requisite.
The second condition refers to the fact that stakeholders interested into the project shall be actively involved into the planning process. Further major token is that the economic evaluation at the level of approximation featuring the various steps of the project cycle feeds and frame the public debate on the project implementation.
This article is based upon results from research activities, enriched with the explanation of few recent case-studies.


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Author Biographies

Silvia Maffii, TRT Trasporti e Territorio

Expert in transport economics and transport planning, she participated to a large number of feasibility studies, cost-benefit analysis of transport projects and urban transport planning, as well as development and application of transport models. She has an extensive professional and research experience in modelling at urban and regional scale and in the assessment of land-use, socio-economic and environmental impacts of transport investment and policies.
Managing Director of TRT Trasporti e Territorio, she is responsible for supervising model applications and transport policies assessment. She is Professor of Transport Planning at the Politecnico di Milano.

Riccardo Parolin, TRT Trasporti e Territorio

As senior expert in economic and financial analysis of transport projects, he has participated to, and has been in charge of carrying out several feasibility analysis, studies for the regulation of public transport, and the evaluation of transport plans. He has also proficiently participated in numerous applied research projects in the transport sector. In TRT he is responsible for the area of economic appraisal of transport projects.


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How to Cite
MaffiiS., & ParolinR. (2011). Transport Infrastructures and Acceptability: the Role of Economic Evaluation for Conflict Mitigation. TeMA - Journal of Land Use, Mobility and Environment, 4(4), 89-98.