By Yves CROZET

Professor at IEP Lyon, Laboratory of the Economics of Transportation

Abstract

Faced with weak economic growth during the past five years, several European countries are calling for more investment in infrastructures for transportation. Many of these projects have run afoul of financial or socioeconomic assessments of feasibility. The return on investment is low, sometimes negative, even when taking into account nonmonetary benefits such as saved transit time or positive effects on the environment. To skirt around this difficulty, new methods of project assessment have been invented in Great Britain and France. Using different approaches to assign an economic value to the “gains in accessibility” due to new infrastructures and new services in transportation, they establish a direct relation between improved accessibility and increases in the GDP. Can we trust them? In general, gains in accessibility cannot be turned into gains in economic growth, unless we adopt very controversial, simplistic hypotheses. Rather than fixating on the growth supposedly resulting from the saved transit time (as in plans for certain high-speed trains), we should investigate another aspect of accessibility, namely: reliability and capacity.