News release

From: The University of Sydney

Sydney and Melbourne increasingly divided at homeownership level

• Sydney and Melbourne are breaking up into multiple centres within the same city, new research shows
• Cities were shown to be divided at the home ownership level, with renters clustering with renters and homeowners with homeowners
• Possible new socioeconomic divisions based on suburb

The cities of Sydney and Melbourne are becoming increasingly polycentric – consisting of several sub-centres rather than radiating from one central business district, a new study by the University of Sydney’s Centre for Complex Systems has shown.

The study, published in The Royal Society, combines publicly available datasets from the 2011 and 2016 census records and the Australian Bureau of Statistics with a cutting-edge population dynamics model to also reveal suburb divisions: homeowners increasingly clustering in suburbs with other homeowners, and renters with renters.

“We also combined large, publicly available data-sets with a model of population dynamics to simulate what Sydney and Melbourne may look like in the near future,” said the study’s senior author and Centre for Complex Systems researcher, Dr Michael Harre.

The commercial centres of Penrith, Parramatta, Campbelltown, and Gosford further emerged as new population focal points, diffusing Sydney's population away from the CBD and creating a poly-centric city that is very different from its current mono-centric layout.

In Melbourne, the same trend was seen in Melton, Epping, Croydon, Dandenong and Frankston.

“The study revealed not only that the two cities are becoming increasingly poly-centric, but mortgagees and renters are clustering with their own, which may indicate new socioeconomic divisions based on suburb.”

The study’s lead researcher Dr Emanuele Crosato said: “Our study found that the highest population of renters are in Sydney and Melbourne’s CBDs. The areas of Sydney with the highest mortgagor populations – owner occupiers – are around Gosford, Penrith, Parramatta and Campbelltown. In Melbourne, they are around Melton, Epping, Croydon, Dandenong and Frankston.”

“The population model has also allowed us to see how, at the suburb level, populations redistribute themselves based on job locations and where the renters and house owners want to live,” said Dr Crosato.

“Along Sydney’s arterial routes – high capacity urban roads , rental costs have increased to nearly match those of mortgagors, which may mean that those renting in these areas will find it more difficult to buy in those areas in the future.

“This is an example of how “big data” can be extended with state-of-the-art dynamical models to provide insights into the distribution of renters and homeowners across a large city.

Director of the Centre for Complex Systems, Professor Mikhail Prokopenko said: “Our work is an example of an exciting new field of research called Complex Civil Systems, and could be used to understand our cities in ways that were previously impossible.”

“Accurate simulations such as this one allows us to address these and many other points that policymakers are looking to answer in the complex evolution of our cities,” he said.

DISCLOSURE

There are no competing interests to declare. The research was funded by the Australian Research Council (ARC) Discovery Project, grant no. DP170102927. Sydney Informatics Hub at the University of Sydney provided access to HPC computational resources that have contributed to the research results reported within the paper.