Abstract

This paper provides a first appraisal of welfare losses caused by urban road freight in the Paris region, including congestion and the main environmental impacts. To do so, we calibrate an aggregate supply-demand model of passenger and freight road transport. Demand is represented by two independent functions, which in practice aggregate OD matrices generated by the freight model FRETURB and by the 4-step model MODUS regarding passenger travel. Supply functions are co-dependent and account for congestion within a multiclass framework, based in practice on the road assignment module of MODUS. We find that the current (un-tolled) situation leads to substantial welfare losses (2M€ per hour). Trucks account for 18% of these losses, though representing only 4% of total traffic. Indeed, the marginal social cost of heavy vehicles is significantly larger than for light vehicles (4.81€/vkm vs. 1.54€/vkm). Still, under reasonable assumptions we find that traffic mitigation efforts should focus more on light vehicles than on heavy vehicles in the Paris region in order to improve social welfare.