Modelling the compact city: capacities and visions for Melbourne

Abstract

The metropolitan planning strategy ‘Melbourne 2030’ was released by the Victorian state government in 2002 as a major step towards a low-carbon city and a counter to urban sprawl; it provides for intensification of land-use within an urban growth boundary focused on activity centres and transit-oriented development. It is now widely acknowledged that this policy has not been implemented, while the growth boundary has been expanded substantially. A primary reason for this failure is the government's fear of negative electoral reaction if Melbourne's much-loved urban ‘character’ is transformed. There has been a lack of both capacity modelling to show where and how the existing fabric can be densified, and of realistic urban design visions that might stimulate the electorate's imagination. This paper has two aims: first, to quantify the capacities for compact growth and, secondly, to use these measures as frameworks for understanding the urban design opportunities embodied in them. Using a combination of GIS mapping and digital modelling tools, scenarios based on transit-related planning principles and urban design criteria are explored as a basis for understanding resident responses. A key finding of this study is that Melbourne does not need a particularly radical change to its built form to achieve substantial increases in gross density. Modest height limits in activity centres and of 4–5 storeys along transit lines are easily enough to accommodate the projected population growth within the existing built-up area. We suggest that if height controls can be properly enforced then this can be achieved democratically and without significant electoral backlash.