A travel behaviour change framework for the city of Cape Town

Abstract

Rapid increase in car ownership, and associated externalities, have motivated Transport for Cape Town (TCT) to develop strategies to curb growth in car use, particularly growth in Single Occupancy Vehicles (SOVs) in and out of the city centre. This paper reports upon the results of a project which sought to develop a framework to guide TCT?s Travel Demand Management (TDM) strategy, based upon a review of theory and a meta-analysis of empirical evidence. This framework includes a TDM strategy scenario in which a set of phased interventions seek to reduce the share of weekday SOV traffic into the city centre by 10% after five years. It is argued, from a theoretical perspective, that the keys to effective TDM intervention include: identifying which trip decision elements should be targeted in the short and long term; recognising which TDM measures are likely to have the greatest impact upon these decision elements; understanding which groups are most susceptible to change so that TDM measures might be targeted strategically; understanding the triggers which lead individuals to deliberately reappraise their travel decisions; influencing the variables that create the necessary circumstances that prompt decisions leading to the desired pattern of ?asymmetry?; and ?locking in? the vehicle kilometres travelled and other benefits, when they accrue. On the basis of the meta-analysis of secondary data, it is contended that financial charging can be expected to register the highest reduction in SOV mode use share, at around 15% at a precinct scale, followed by financial incentives, regulatory and voluntary measures at around 5%, 3% and 2% respectively. It is suggested that with the correct packaging, sequencing, targeting and resourcing, a 10% reduction in the SOV mode share of traffic travelling in and out of the city centre could be achieved.