Costs of Interchange: A Review of the Literature.

Interchange within mode influences the demand for that mode through the effect it has on time spent waiting, time spent transferring between vehicles and the inconvenience and risks involved, whilst interchange between modes has additional implications in terms of information provision, through ticketing and co-ordination. The valuation and behavioural impact of each of these factors will vary with an individual’s socio-economic and trip characteristics as well as with the precise features of the interchange.

A reduction in the costs of interchange brought about by an improvement to any of the above factors will lead to increasingly ‘seamless journeys’ and such benefits which must be quantified. Indeed, this issue has been identified as an area of key importance in the Government’s Transport White Paper (DETR, 1998a) which states:

Quick and easy interchange is essential to compete with the convenience of car use.

This message was reiterated by the draft guidance for Local Transport Plans (DETR, 1998b), which called for:

more through-ticketing, better connections and co-ordination of services, wider availability of information and improved waiting facilities.

Rather than being perceived simply as a barrier to travel, quality interchange is now also being regarded as an opportunity to create new journey opportunities. A recent report on the subject of interchange (Colin Buchanan and Partners, 1998) claimed that :

It will become more sensible and economic to base public transport networks around the concept of interchange rather than the alternative of trying to avoid it.

whilst in response to the diffuse travel patterns made possible by increased car availability, CIT (1998) commented:

people should readily be able to complete a myriad of journeys by changing services (and modes) if a through facility is not available. Ease of interchange should be something we take for granted.

Regardless of the precise direction in which transport policy and public transport provision develop, practical constraints and the fact that the most heavily trafficked routes tend to have through services places limitations on the extent to which the need to interchange can be reduced whilst no matter how fully integrated different modes of transport are the need to transfer between them cannot be removed. In contrast, the need to change would inevitably increase with the adoption of a practice of building networks around interchange to create new journey opportunities. However, there is considerable scope to improve existing interchange situations or to design new ones which impose minimum costs. Although previous empirical research has focused on the need to interchange or not, and this remains important, it is essential that research is also directed at improvements which facilitate interchange.The aims of this study, as set out in the terms of reference, are centred around the demand side response to interchange rather than the technical supply side issues relating to improving interchange and integration which have been covered in other studies (Colin Buchanan and Partners, 1998; CIT, 1998). The objectives are:

to explore the extent to which the reality and perception of interchange deters public transport use, absolutely and in relation to other deterrents

to investigate how public transport users perceive interchange; how they make choices and trade-offs in travel cost and time and the influence of interchange attributes (e.g. information, through ticketing) on those choices

to assess which components of interchange act as the greatest deterrent to travel

to investigate the extent to which interchange penalties vary according to journey purpose, distance and time of travel (or other factors).