Traffic congestion in Australia’s major cities is set to worsen and could cost the nation more than $50 billion in lost productivity by 2031 unless addressed, says the Committee for Economic Development of Australia (CEDA).
CEDA says that Sydney, Melbourne, Brisbane and Perth - which generate 80 per cent of Australia's GDP - will need to accommodate 5.9 million more people by 2031.
Given the low population density in the metropolitan areas, those living further out have to drive further to get to their jobs and generally make longer road trips.
At the same time, says CEDA, there has been chronic underfunding of infrastructure in Australia's capital cities.
"Without action the cost of congestion could rise to more than $50 billion annually by 2031, with the demand for key urban rail and road corridors projected to exceed current capacity by 2031," CEDA said in a report on Australia's agenda for economic growth.
CEDA said public investment in infrastructure had been restrained by perceived budget constraints.
Also, allocating the available budget had shown insufficient regard to maximising the overall social benefit, and the politics involved had been less transparent than desirable.
The potential for the private sector to contribute more to infrastructure had been under-utilised partly because of unclear and unstable long-term planning by public authorities.
"For the prosperity of the entire country, it is increasingly important that the nation's major cities work efficiently," CEDA said.
"For this reason, it is important that governments put in place mechanisms for the establishment of published long-term plans for infrastructure development."