Australia's population is expected to grow at 1.3 per cent a year to 2055, resulting in a population of 39.7 million - an increase of 60 per cent.5 The composition of the population is also changing. Like many countries, Australia has an increasing number of citizens aged 65 and over, with the number of Australians in this age group projected to more than double by 2055.6
Australia is also highly urbanised with 86 per cent of Australians living in cities and towns.7 Almost half of the country's 23.7 million people live in Sydney, Melbourne and Brisbane. Populations for the four largest cities - Sydney, Melbourne, Brisbane and Perth - are projected to reach 18.6 million by 2031.8
Urbanisation, population growth and the ageing population are placing increasing pressure on social and economic infrastructure. These factors are driving an unprecedented need to build more infrastructure and use existing infrastructure more efficiently. The Australian Bureau of Infrastructure, Transport and Regional Economics (BITRE) estimates the economic cost of congestion in Australian capital cities could be as high as A$37 billion in 2031.9