Melbourne density

London density
Population density of Melbourne vs London at same scale and same key (source: Charting Transport)

The managing director of planning at Transport for London, Richard de Cani, reportedly claims Melbourne is five times bigger than London even though it only has half the population.

Five times bigger? The Age has been promoting this myth for years; here it is back in 2010 asserting that “Melbourne is already the eighth largest city in the the world in geographical size”.

It might reinforce the preconceptions of many in Fairfax’s target demographic, but this old canard is seriously wrong on two counts.

Fortunately, we can refer to the estimates of population density for a range of world cities at the same scale put together recently by Chris Loader, including both London and Melbourne (I discussed Paris yesterday; see How dense are our cities compared to Paris?).

The first error is evident from the exhibit. London isn’t a mere one fifth the size of Melbourne; its urbanised footprint is at least as large.

The sizes of cities can’t be usefully compared on the basis of their administrative boundaries; borders can be drawn anywhere on a map and are often determined by local political convenience. (1)

The area of contiguous urbanisation is a much better measure (e.g. the area under streetlights), but it has limitations too; in partiular, it doesn’t capture suburbs separated by green belt or water.

For example, the satellite suburb of Melton is separated from the main urban fabric of Melbourne by 9 km of green belt (known locally as green wedge) but almost 60% of its workforce commutes to ‘mainland’ Melbourne.

It can be labelled a city, a town, or a village, but it’s as economically and socially connected to the rest of the metropolitan area as any other outer suburb.

Defining where a city ends is a difficult task, but any sensible approach should start by taking account of connections, particularly the extent to which workers in a suburb or town commute to jobs in the rest of the urban area.

After all, agglomeration economies, especially in labour, are the reason cities exist. Outlying towns that are closely connected to the continuously urbanised area should be considered part of the main city.

The second error is the claim that Melbourne’s population of 4.2 million is half that of London’s. It’s true the population within London’s green belt is circa 8 million, but there’s close to a further six million living beyond the green belt.

London is surrounded by an extensive system of ‘overspill’ or satellite towns like Hemel Hempstead and Milton Keynes that are economically and socially connected to London. They’re as much outer suburbs of London as Melton is of Melbourne.

London’s commuter belt covers much of the South East region and part of the East of England region, including the Home counties of Kent, Surrey, Berkshire, Buckinghamshire, Hertfordshire and Essex.

The important spatial difference between London and Melbourne isn’t geographical spread; it’s the fact London is both a lot denser and has a more decentralised form. Chris Loader estimates London’s population-weighted density (the best way of measuring density) is three times Melbourne’s.

Mr de Cani no doubt knows his stuff, but being drawn by the media into discussing places you’re visiting is fraught. The local media tends to have its own agenda. (2)

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  1. When I was a child I was under the delusion that Brisbane was the third largest city in the world. Years later I learned what that really meant is the Brisbane City Council covered one of the largest administrative areas of any municipality in the world.
  2. The Age says it even managed to draw a comment from Mr de Cani on the VCAT Nightingale apartments decision I discussed last week (see Are councils dealing with the problem of inner suburban parking?); indeed, the paper made it the angle of its story i.e. Car-free housing encouraged in London, says city’s transport planning boss. The VCAT decision is such a specific and complex subject it makes me wonder if perhaps Mr de Cani was speaking more generally than The Age implies.