The carbon devil in the detail on urban density

Paul Mees of RMIT has compiled and compared official data on the density of North American and Australian cities. His peer-reviewed work shows that the densest city in the United States is not New York but Los Angeles, which few Australian urbanists aspire to emulate.

Sydney, Australia’s densest city with 20 persons per hectare is only three quarters as dense as Los Angeles, which has 27 persons per hectare. Yet public transport commuting in Sydney is five times the Los Angeles rate. Transport policy, Mees argues convincingly, is at least as important as urban form in shaping a city’s transport outcomes. Density is not destiny.

With high-rise urbanism facing scientific doubts, its advocates often decorate their arguments with circumlocutions about the aesthetic or cultural qualities of high-rise living. These claims are usually subjective and contestable. For every high-rise architectural masterpiece there are dozens of shoddy apartment blocks thrown up with little ecological or aesthetic concern.

The supposed “vibrancy” of high-rise living is often balanced against provision of green open space, especially at the neighborhood scale. Children’s development advances through free physically active play but a recent literature review by my colleagues Jason Byrne and Neil Sipe argues planning for higher densities rarely considers children’s needs. Blubberville anyone?

Why then have views favoring high densities gained traction? Despite the waning of the old cultural cringe, a view persists of Australia’s essential suburban character – where most of us live – as artless against the boulevards of Europe or the boogie-woogie of New York.

The intellectual misadventure of high-rise urbanism also perpetuates a pernicious bias in Australian environmental debates in which less affluent suburban dwellers are treated as environmentally unsophisticated “bogans” – a stereotype recently denounced by Melbourne University’s David Nichols.

It fits within a long and regrettably continuing Australian tradition of denigrating suburbia whose recent version sneers at “aspirationals” in suburban “McMansions” driving “monster-trucks”. That complaints about suburban consumption lack objective scientific foundation, raises suspicions that the anti-suburban prejudice serves to deflect scrutiny from the more harmful consumption patterns of wealthier – and typically denser – inner urban households.

Those who criticise high-rise urbanism, though, risk being cast as apologists for urban sprawl. Disagreeing with Sydney’s Barangaroo proposal, for example, doesn’t equate to support for the latest fringe growth area splurge.

More single, detached dwellings in low-density estates at the suburban fringe also causes harms. These range from the destruction of bio-diverse habitats to the social isolation of new residents from work and services. My own work on household oil vulnerability clearly reveals the future perils from higher fuel prices already planned into the fabric of many of our car-dependent fringe suburban zones.

So how dense should we be? One possibility is a mid-level suburbanism. Focused nodes of three to six storey developments – terraces, walk-ups and low-rise apartments – are dispersed across an entire metropolitan area, not just inner zones. Tied to an employment decentralisation program where more jobs exist outside the CBD, such nodes can then be used to anchor improved suburban public transport networks.

As Paul Mees has shown, suburban densities can easily support high quality public transport if we plan our networks effectively. Such a model can accommodate new residents more widely across the city, and avoids the ecological damage of very high or low densities.

There is an even better solution to the density debate though. Maybe we should abandon our obsession with density as a driving objective of urban policy and instead design our living environments to best accommodate our overall economic, social and environmental goals, at whichever scale is most appropriate.