To inform their LGMS, badged ‘City Shape’, Brisbane has embarked on an extensive consultation process through ‘festival style’ Neighbourhood Planning Fairs featuring notable urban designers Marcia Hines and the Hooley Dooleys, as well as follow up local area workshops. They were however, an impressive attempt to engage, educate as well as entertain. At the Fairs, four conceptual models for City Shape were presented; Centralised, Multi-Centred, Corridor and Dispersed, with an assumption that one of those strategies was preferred or ideal. Many questions arose.
Each of these urban forms is evident in Brisbane now and why is there a need to choose one over the other? How much of what, where, seemed a more relevant and much harder question. What is a regional centre within the broader region? How big is it? Does it have a series of inner urban neighbourhoods with its own localised bus service? Similarly, with significant investment in busways proposed, what is the appropriate form and scale of an urban corridor? Do corridors exist on their own or connect to other centres? How are they different to the existing rail corridors, many of which pass through relatively low density traditional (and highly valued) neighbourhoods?
In order to conceptualise these issues, an idealised diagram of a city of 1 million people was created with the four major sub-regional centres of Brisbane surrounding the city centre, interspersed with four smaller centres all linked by large and small corridors across a field of smaller neighbourhoods. Typologies for hamlets, towns and corridors, both large and small were then prepared, using combinations of five minute (400m) and ten minute (800m) walkable catchments. These were overlaid with densities from 15 dwellings/ha to 200 dwellings/ha to show how various densities could be incorporated into each typology to create more sustainable urban forms.
These ideas are provocative and need further development and explanation, although a recent application in Maroochydore Shire on the Sunshine Coast showed their promise.
If urban designers are to productively communicate complex ideas about urban form, structure and growth, conceptual tools like these diagrams can assist to give form and structure to the debate.