Australia is one of the least densely-populated nations in the world, with our cities and architecture being designed accordingly. But what will happen when our population inevitably grows?

Population density definition

Population density is defined as the number of people living in a unit of area (eg. The number of people per square kilometre). The population density formula is simply: population ÷ area.

Australia’s population density

As of 2019, Australia has an estimated population of 25.09 million. According to the latest UN data, Australia has a population density of 3.22 people/sq km. This puts Australia at 228th in the world in terms of population density, sitting between Iceland and Namibia.

Population density by city

The most populated city in Australia is Sydney, with a recorded population of 5.48 million and a density of 407 people/sq km. The least populated city in Australia is Darwin, with a population of 148,564 and a density of 703 people/sq km. Despite a population of 2.48 million, Brisbane only has a density of 145 people/sq km. 

Australia’s population density by state and territory

Among the states and territories, the Australian Capital Territory has the highest population density at 171 people/sq km, followed by Victoria (27), NSW (9.7) and Tasmania (7.6). The remaining states and territories have population densities below the Australian figure, with the Northern Territory having the lowest population density at just 0.2 people/sq km.

Population density by country

The most densely populated country is Monaco (26,105.37 people/sq km). The second-most dense country is China Macao SAR (21,151.10), while the least densely populated country is Greenland (0.14).

The world’s most dense cities

Monaco and China may be the world’s most densely populated countries, but the cities with the highest population density include Dhaka, Bangladesh (44,500 people/sq km), Mumbai, India (31,700 people/sq km) and Medellin, Colombia (19,700 people/sq km).

Population density and architecture

When the population becomes more dense, this tends to impact architecture in that there is an influx of apartments and high-rise buildings as well as a lack of green space. Stress is also placed on transport and other infrastructure which needs to be developed quickly to serve these growing cities.

This can sometimes result in building defects, as has been seen a number of times in China for example, which is a very densely-populated nation. Australia is not immune to these problems and it is important that we plan appropriately for development before population growth.

One of the biggest issues we are starting to deal with is housing. With more and more people clustering around big cities rather than rural or farm areas, there is an increasing number of families living in apartment dwellings. The problem with this is that many of our new apartment dwellings are geared towards investors and luxury buyers and there is a lack of affordable medium-density housing. Countries like Sweden are a good example of how apartments can be family-friendly, with most apartment buildings being built on the “human scale” of three to five storeys.  

It is also important that we preserve our green space and create places for communities to gather, as a way to reduce the social isolation that can be prevalent in big cities, and to promote health and activity among residents. Parks and playgrounds are also crucial spaces for children to play, grow and develop.

Finally, while this is currently not common in Australia, as the population grows we will need to consider the flexibility of private and semi-private property. Spaces such as schools could easily be opened up to the community after hours for a wide range of activities, like the pioneering South Melbourne Primary School.


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