External Factors That are Likley to Affect Travel Patterns

Primary Author :Steven Piotrowski

Co-authors : Hugo Wildermuth

Organisation: Consultants, Department of Transport, WA


As part of the Perth Transport Plan for a City of 3.5m people, long range transport modeling was undertaken using strategic travel models.The strength of conventional transport models is in short-to-medium term projections, in realistically distributing demand among the thousands of origin-to-destination pairs, and in differentiating between various activity centres and between peak and off-peak travel. The weakness of the current models is that they do not explicitly allow for changes in people’s travel behaviour in response to “external” factors not directly related to the transport system. Two travel behaviour scenarios were considered: a “Base Scenario” employed traditional modeling and a ‘business as usual’ situation. The “External Influence” scenario was expected to include changes to travel demand as a result of expected changes in the external operating environment for transport such as the introduction of autonomous vehicles.


A workshop was held with 20+ Perth-based transport experts who were asked to rate qualitatively the expected impacts on travel demand of changes to several “external influences” including: socio-demographic, employment, education, shopping, ITS, and other technology. The anticipated impacts on land use, road capacity, daily trip rates, car usage, public transport usage, active transport, peak period travel, commercial vehicle trips and value of travel time savings were estimated and tabulated.