Planned spatial restructuring of Australian cities: Are the transport benefits of employment decentralisation policies greater than those of transit-oriented development?

Perth and Brisbane are both subject to new state government office decentralisation policies. Unlike residential Transit-Oriented Development (TOD), which is proving difficult to achieve in practice, moving workplaces out of Australia's highly centralised city centres is proving easier for governments to enact. Urban restructuring via employment decentralisation is thought to offer specific transport benefits and risks, yet these are mostly unexplored in the contemporary Australian context. This paper explores whether the transport benefits of planned employment decentralisation policies are greater than those of residential TOD, to help gauge whether Australian planners should give support to the decentralisation agenda. The efficacy of residential TOD as a means to change travel behaviour is summarised from a systematic review of previous studies. Modelling of an idealised employment decentralisation scenario for the year 2031 was produced for Brisbane to generate a set of likely travel behaviour changes. Methods for doing a comparative scenario for residential TOD are developed. The results suggest that planned decentralisation can improve transport systems and sustainability, particularly by reducing vehicle travel times, albeit after the short-term dislocations of workplace moves are resolved. The research brings into question the overwhelming and continued focus of much of the planning profession on residential TOD as the main (and sometime only) transport and land use intervention being harnessed to help alleviate traffic congestions and generate sustainable travel behaviour. A broader focus on urban structure in metropolitan transport and land use policy and planning appears warranted.