Some interesting analysis of the politics in this issue. Goodwin notes that the use of revenue from congestion charging is an essential part of any scheme, in which “the beneficiaries were as visible and influential as the motorists who paid it” even if the only goal is to reduce congestion, not to raise revenue. In London's case, the revenue was funneled to public transport improvements. He also notes the implications for modelling: the traffic reduction was at the upper end of the range estimated by models, and the revenues from the scheme were hence lower than expected. “This is not particular to road pricing: it is part of a general reappraisal of establish transport modelling techniques, which have a built-in tendency to underestimate the range and complexity of the behaviour response to policy, which in turn causes an overestimation of the benefits of infrastructure expansion, and an underestimation of the benefits of demand management.” In a footnote, he adds that “some of the earlier modelling work had actually forecast a bigger effect, closer to what happened, but this had been progressively revised downwards by the modelling teams in order to produce robust, defensible, conservative assessments.”

Keywords: congestion pricing, urban politics, transport modelling

Keywords: transportation demand management

Keywords: transport modelling

A recent article by Prakash et al. (Applied Economics, 33, 1579-85, 2001) asserted that induced travel effects do not occur. This paper is criticized on several grounds. It disregards much of the recent work in this area that has empirically estimated induced travel relationships. The models specified are inappropriate for properly addressing this question, both in their use of road expenditure data (based on a misunderstanding of how this may relate to traffic growth) and specification of a model that does not account for other variables that generally have a large effect on traffic growth (notably population and income growth). The evidence in the literature is summarized and an analysis of UK road expenditure data shows that expenditure is not a good measure of actual road capacity that is built.

Keywords: transport planning, urban planning

Reallocating roadspace from general traffic, to improve conditions for pedestrians or cyclists or buses or on-street light rail or other high-occupancy vehicles, is often predicted to cause major traffic problems on neighbouring streets. This paper reports on two phases of research, resulting in the examination of over 70 case studies of roadspace reallocation from eleven countries, and the collation of opinions from over 200 transport professionals worldwide. The findings suggest that predictions of traffic problems are often unnecessarily alarmist, and that, given appropriate local circumstances, significant reductions in overall traffic levels can occur, with people making a far wider range of behavioural responses than has traditionally been assumed. Follow-up work has also highlighted the importance of managing how schemes are perceived by the public and reported in the media, with various lessons for avoiding problems. Finally, the findings highlight that well-designed schemes to reallocate roadspace can often contribute to a multiplicity of different policy aims and objectives.

Keywords: transport planning, streets, roadspace reallocation

Keywords: transport modelling, transport planning

Keywords: transport modelling, transport planning, roadspace reallocation

Keywords: transport modelling

A good overview of progress from the 1960s “predict and provide” approach to the current idea that road capacity is fundamentally a policy decision.

Keywords: transport modelling, history, transport planning

Keywords: induced travel, land use transport link

Keywords: streets, transport planning

Keywords: transport planning

Keywords: congestion pricing