Impacts of full cost pricing on the sustainability of urban transportation: towards Canada's Kyoto commitments

Certain concerns about sustainable transportation derive from the premise t hat significant atmospheric concentrations of carbon dioxide (CO2) and othe r greenhouse gases which contribute to global warming can be attributed to automotive emissions. Among measures considered to curtail automobile depen dency and increase transit modal split, "full cost pricing" - a means of ex tracting both environmental costs and hidden subsidies which road users all egedly impose on society - has emerged as an increasingly popular suggestio n. This paper examines the potential impact of full cost pricing on the "su stainability" of urban transportation, using Toronto as a case study. The a nalysis deals with the direct effects on mode choice and vehicle utilizatio n resulting from increased user costs as might be achieved through fuel tax es or road pricing, as well as the indirect, longer term effects on locatio n decisions. To investigate the land-use impacts, population distributions were altered to reflect more compact development and less urban sprawl as a proxy for relocations that might result from an increase in the costs of a utomobile use. Impacts are presented in terms of changes in total peak peri od vehicle-kilometres, mode split, and CO2 emissions. Despite several quali fications related to modelling techniques used in the case study, the analy sis suggests that, overall, the impacts of large increases in road user cos ts appear to be less than proponents of full cost pricing would expect. In addition, the analysis suggests the fairly obvious, namely, that the greate st impacts of pricing occur within those choice markets where reasonable al ternatives to the private automobile actually exist.