A Multi-Criteria Analysis as a Rational Evaluation Process for Building a New Highway in Italy

Abstract

The low accessibility of transportation to the main Italian touristic places (during the summer period) produces road congestion that is often high and negative environmental impacts (externalities). This is the case of the coastal area between Cesena and Venice, which is particularly affected by this phenomenon because of a unique local road, the Romea: it allows car trips among all these touristic places. Beginning from these considerations, the realization of a new highway was proposed, to improve transport accessibility to this area. A Multi-Criteria Analysis (MCA) was identified as the rational evaluation process to verify the sustainability (economic, social and environmental) of this transportation project. The aim of this paper is to describe the MCA evaluation analyses applied to this case study, underlining the main results obtained. One of the main findings of the research was the applied evaluation methodology. A rational and participated weights definition criterion process was implemented, through a "Delphi method" within a Public Engagement process. The MCA results show that the best design alternative is the construction of a highway plus the realization of a "green-way". Furthermore, we found that the estimated non-user's benefit incidence was about 80% of the total, underlining the appropriateness in using this evaluation method, useful to better quantify non-monetary externalities (versus the cost-benefit analysis). Finally, to verify the robustness of the results we also performed a sensitivity analysis, confirming the main results.

Decision-Making in the Transport Sector: A Sustainable Evaluation Method for Road Infrastructure

“…The CBA method, thanks to both national and EU guidelines [35,36], is more standard and less discretionary, enlarging the consensus, legitimizing the analysis, and reducing the risk of planning fallacy [37]. However, the CBA have some limits, tending to underestimate externalities (non-monetary impacts) such as the environmental, landscape, and social impacts [9,26,37,38]. On the contrary, the MCA, which with several multi criteria approach, aims at identifying the best "compromise" solution, is more suitable for the non-users (and non-monetary) impacts estimation.…”

A Sustainable Evaluation Processes for Investments in the Transport Sector: A Combined Multi-Criteria and Cost–Benefit Analysis for a New Highway in Italy

“…Definitely, the multi-criteria analysis generally allows a more reliable estimation of the non-users' impacts [78][79][80][81][82][83][84] (e.g., non-monetary externalities such as greenhouse gas emissions, naturalistic impacts, aesthetic quality) that are generally underestimated with cost-benefit analysis. On the other hand, cost-benefit analysis is a more standardized and less discretionary procedure (e.g., application of the national and/or the EU guidelines [85,86]) and it is commonly considered a "solid" evaluation method to reduce the risk of planning fallacy and minimize conflicts over decisions (enlarges the consensus).…”

“…Due to the different measurement units, a normalization process must be performed. There are several normalization techniques (e.g., [80]). The successive step of the MCA is the "weight" estimation, aiming to define the importance (the weight) for each criterion compared to the others.…”

“…The definition of the weights is a crucial activity that could impact on the decision-making result and for this reason it is important that all the stakeholders involved in the process can express their judgments. There are several methods to define these weights (e.g., Delphi method, stakeholder engagement, for details see [80]).…”

“…Table 10 (evaluation matrix) shows the results derived from the analysis. For details on the estimation of the indicators (qualitative/quantitative) for the three project scenarios reported in Table 10, see [80]. The design Scenario 1 "stand alone" produces the lower benefits both for users and for non-users but also presents the lower investment costs.…”