Twenty years of urban growth and change

Australia is said to be one of the most urbanised countries in the world. The 2021 Census showed that 90% of the population lived in urban areas with more than 1,000 people. This blog looks at the growth of urban areas in Australia over the period 2003-23. What are Australia's largest urban areas? Which ones have grown the most? Read on to found out.

Defining "urban"

There are many ways to define "urban", but this blog uses Significant Urban Areas (SUAs). These are defined by the ABS and are designed to provide a spatial unit of analysis for urban areas with more than 10,000 people. An advantage of this geography is that population estimates are calculated on an annual basis (ie the ERP). This is distinct from urban centres and localities which are only available in Census years. 

What are the largest urban areas in Australia?

The table below shows the ten largest SUAs by population in 2003 and 2023. There were two key changes over these twenty years. Firstly, Melbourne replaced Sydney as the largest SUA in Australia (more on that below). Secondly, the rankings were relatively unchanged, with only new entry in the top ten (Sunshine Coast), and a corresponding exit (Wollongong). 

Australia is dominated by five large cities, each with over 1 million in population, and the two largest now exceeding 5 million. This dominance of large cities is a legacy of our colonial history and the concentration of the export economy in the state capitals. The capital cities in Australia's states are much larger than their secondary cities, a phenomenon known as urban primacy. For instance, Sydney's population is almost ten times that of Newcastle-Maitland, the second largest SUA in New South Wales. However, The level of urban primacy is extreme in South Australia, where Adelaide (1.43 million) is almost 50 times larger than the regional city of Mount Gambier (30,580).

Australia now has an additional SUA with a population exceeding 500,000. Gold Coast-Tweed Heads (735,210) and Newcastle-Maitland (526,520) were joined by Canberra-Queanbeyan in 2023, which now has a population of 503,400. Of these, Gold Coast-Tweed Heads recorded the strongest annualised growth rate over the twenty years (2.3%). 

When will the Gold Coast become the sixth member of the 1 million plus club? It's not something that can be easily assessed as population forecasts are not produced for SUAs. It's further complicated on the Gold Coast as the SUA crosses a state border into NSW to include Tweed Heads. This makes sense from a urban measurement perspective as the two areas are contiguous but it does highlight some of the issues in measuring "urban".

Population forecasts (medium series) produced by the Queensland Government Statistical Office indicate that the Gold Coast LGA (ie does not include Tweed Heads) will have a population of 983,000 at 2046. Even with the future population of the Tweed Heads section added to this, and based on current assumptions, it's likely that Australia will not see another SUA exceeding 1 million for some time.

No urban areas in Tasmania or the Northern Territory ranked in the top ten. The largest SUA in these states is Hobart (population 232,450) and Darwin (137,002) respectively.

The great rivalry - Sydney vs Melbourne

The graph below shows the population of Sydney and Melbourne over the period 2003-2023. In 2003, the population of Sydney exceeded Melbourne by 300,000. However the rapid growth of Melbourne, particularly after 2006, saw the difference between the two cities contract. Melbourne's population overtook that of Sydney in 2018. By 2020, Melbourne's population exceeded Sydney's by more than 68,000. 

In 2021, the population of both cities declined as a result of extended COVID lockdowns, as well as an exodus of international students and other temporary visa holders out of the country. The impact was felt harder in Melbourne, where the population declined by around 87,000 in 2020-21, against Sydney's loss of around 35,000 people. However the post-COVID rapid surge in overseas migration has seen both cities resume a strong growth trajectory. As the table above shows, Melbourne's population is 5.103 million in 2023, compared to 5.041 million in Sydney - a difference of 62,250 people.

But is Melbourne really the largest city in Australia? The joys of geography really comes to the fore in this example. The SUA geography is different to other measures such as the Greater Capital City Statistical Area, or the combined total of LGAs in the metropolitan area (a measured often used by state governments). Perhaps the most diplomatic answer is that Melbourne and Sydney are roughly the same size - depending on how its measured.

What urban areas grew the most?

The table below shows the fastest growing SUAs over the period 2003-2023. There were 13 SUAs that recorded an annualised growth rate of 2% or more. Many of these were located within the peri-urban area surrounding the state capitals, or along the coast. They tend to attract new residents such as families and retirees seeking lifestyle opportunities. Warragul-Drouin, located south east of Melbourne, heads the list, closely followed by Busselton (Western Australia) and Airlie Beach-Cannonvale (Queensland). All three SUAs recorded an annualised growth rate exceeding 3.0%, and their populations almost doubled over the twenty years. 

Only six SUAs recorded population decline over the twenty years. These were Broken Hill, Mount Isa, Lithgow, LIsmore, Whyalla and Port Pirie. With the exception of Lismore, all of these SUAs are long established mining centres. However structural change in recent years has impacted job opportunities, and out migration of young adults further entrenches population decline. This trend is played out across the country in many smaller settlements, particularly in agricultural and remote areas.

Although Lismore's population was relatively stable over the twenty year period, devastating floods in 2022 resulted in the loss of many homes and subsequent loss of population as people moved elsewhere. In 2023, the population declined by -1.6%. Reconstruction work and flood mitigation are ongoing and it remains to be seen how quickly Lismore regains its population.  

Summary

Australia is a highly urbanised country with a small number of large cities. There were five cities with a population exceeding 1 million in 2003 and 2023. Despite strong growth on the Gold Coast, it's likely to be some time before it reaches this milestone. Between 2003 and 2023, Melbourne overtook Sydney to become the largest urban area in Australia. This is despite both cities recording population decline in 2021 due to COVID restrictions. SUAs with the strongest growth over the twenty years were located in peri-urban or coastal areas. Only six SUAs recorded population decline between 2003 and 2023.