The 7 Million Sustainable Dense City?

Australia has only 23 million inhabitants, but the population is increasing by 1000 people a day. This is maybe not so remarkable in a world where the population is increasing by 100.000 people a day. But for Australia this equals 1.6 % annually, and for the world (only) 0.6 % annually.

But housing 1000 new people a day requires a lot of new homes and rising house prices. New homes requires land, streets, water, power etc, and more people requires more parks, playing fields, shops, cars, transport, wifi etc. But sadly, the cities of Australia are growing as much outwards as they are growing inwards.

20-40 million new inhabitants require a different approach
Sydney and Melbourne as the two largest cities and Brisbane and Perth as the two most growing cities (in terms of proportion), are still partly stuck in a 1950s planning regime, where suburban lifestyle and the car is dominant, despite that household sizes are decreasing, people are growing older and there are fewer children around.

By mid twenty-first century the population of Australia may almost double to 43 million inhabitants and by the end of the century almost tripled to 62 million inhabitants. Then Australia may be the tenth most populous South-Eastern Asian nation. However, in doubling its population, the country may need to double the densities at which people live within its larger cities.

Me observing and reflecting upon the city center life outside the Central Post Office of Brisbane.

My time in Australia is coming to a close. I have thoroughly enjoyed my seven weeks in Sydney and two weeks in Brisbane. I also spent a weekend in the bushland north of Sydney. I have experienced how two large and rather suburban cities function, and observed with joy and horror their approach to a rapid growing population. I've met some very wonderful people, many who were recent immigrants from either Europe or Asia.

During my last three weeks in Sydney, I have spend a lot of time swimming in the sea, half the time next to my house in Double Bay, jogging around my neighbourhood of Bellevue, visiting the beaches at La Perouse twice, Middle Head twice, Watson Bay once, Nielsen Park once, Otford once, travelling on the ferry to Circular Quay and to Watson Bay, swimming at the pool at Woolloomooloo and kayaking half way to Shark Island.

Leaving Australia for Europe makes me somewhat sad and exiting. Sad because I leave Sydney in late summer but before the autumn starts for real. Exiting because I arrive in Europe in early spring, but maybe a little too early as there is still snow in much of northern half of the continent.

2-3 million new inhabitants in one city alone
In Sydney and Melbourne, that may sound like an utopian dream or nightmare, but it may not be so difficult. Thinking back 50 years, there were few high risers, and thinking forward, many parts of the two cities would benefit from more medium high rise living. By doubling the proportion of the two cities with double the average density, the two cities could accommodate half as many people as today, increasing from 4-4.5 million to 7 million inhabitants. And a similar pattern could be applied to Brisbane, Perth and other cities throughout Australia (and elsewhere), with the ratios a little different.

Doubling the proportion of the city with double density may not seem so difficult. But increasing the density in already high density districts may seem a much more daunting task. But by targeting the lower density developments within a designated district and replacing it with double the highest density in the same distinct, densities could substantially increase in the designated district as a whole. In other words, the most important may be do identify the lower density developments close to higher density developments that could be subject to (much) higher densities. The reason for this, is that these areas are the ones that could offer the largest gain. This approach would be in contrast to an approach that would aim to achieve higher densities throughout (the entire) designated district.

Sydney's Hyde Park where residential buildings heights are restricted along west (right) and east sides but less so along south side (left).

Preserving identity and heritage
In terms of identity and heritage, this choice of approach could be more successful, as some of the higher density developments may have qualities that would be valuable to preserve. This could be a high street, historically with higher density. So rather than increasing densities in the high street itself, densities could be increased (substantially) in the side streets, where (historically) densities are lower, preserving the older higher density high street. This should of course not be seen as a blanket ban on increasing densities elsewhere within a designated district, but in areas that already have higher densities, the approach could be more cautious.

Of course this approach would result in the loss of a large part of low density developments adjacent to and within higher density areas, but this may be a long term gain for a wider community, as the concentration of services and functions within the (new and larger) higher density district would increase as a result of many more people living within such a higher density district. This approach does not mean that all the lower density development must be replaced with densities double the highest density development. But it will mean that all the (designated) lower density development must be replaced.