The director of the Australian Demographic and Social Research Institute, Peter McDonald, said the natural constraint of the Blue Mountains would force the city to spread to the north and south, until it eventually met growing populations in Newcastle and Wollongong.
”I think you will see the coming together of those three cities into a single urban area,” Professor McDonald said.
”It isn’t simply that the Sydney metropolitan area will continue to grow. I think at some point people will actually choose Wollongong and Newcastle over Sydney to avoid the crowding and congestion and the cost of living.
”But the end result is that they will probably end up living in a larger metropolitan area anyway, with Sydney at its centre and a continuous urban link to those regional centres.”
Planners and experts in health and sustainability said a 50 per cent increase in Sydney’s population would require tens of thousands of additional hospital beds and nearly a million new homes. The amount of water consumed for household use would increase from 1.3 billion litres a day to 2.1 billion litres, requiring a far greater utilisation of water recycling or a new dam.
”In the Sydney basin we may not be able to sustainably meet this population increase,” said Dr Chris Dey, a sustainability expert from the University of Sydney. ”We need greater diversification – more harvesting, recycling, more reuse of waste water.”
Stuart White from the University of Technology’s Institute for Sustainable Futures said public transport and housing would be greater challenges. ”These are major pieces of infrastructure that must be integrated into the city on a mass scale and that is an extremely difficult task, particularly when you’re starting from the position we’re in now.”
While the Prime Minister, Kevin Rudd, welcomed the population increase, Labor backbencher Kelvin Thompson said Australia was ”sleepwalking into an environmental disaster”.
”Another 13 or 14 million people will not give us a richer country, it will spread our mineral wealth more thinly and give us a poorer one,” Mr Thompson said. ”It will make a mockery of our obligation to pass on to our children a world in as good a condition as the one our grandparents gave to us.”