Food, oil shortages predicted as population soars

Perth already runs more than 100km along the West Australian coastline. Photo / Thinkstock

CANBERRA - Australia's big cities are eating the nation's future as they spread out across shrinking farmland, increase pollution, threaten water supplies and hit the quality of life.

A study confirming earlier research warns that these problems will grow as pressures from immigration trigger even greater urban sprawl, massively increasing the size of state capitals within four decades.

"The magnitude of the impacts at all [projected] net migration levels suggests that, unless substantial and timely actions are taken to address these impacts, some have the potential to disrupt Australia's economy and society," the National Institute of Labour Studies report said.

The Government is already reducing net overseas migration from a record 298,000 in 2008-09 to a target of 215,000, although the Opposition pushed for a far lower level of 170,000 during last year's election.

Pressures have already been starkly demonstrated by a housing shortage that has made Australian homes the least affordable in the latest annual Demographia International Housing Affordability Survey.

Urban Taskforce chief executive Aaron Gadiel said Australians were increasingly being priced out of the market.

"Australia's housing shortfall is close to 200,000 homes, with a projection for it to grow to 308,000 dwellings over the next four years," he said.

But the nation's vast urban sprawl - Perth already runs more than 100km along the West Australian coastline - has alarmed policymakers.

Treasury Secretary Ken Henry warned in 2009 that population would grow by 13 million, or 60 per cent, over the next 40 years, with Perth expanding by 106 per cent, Melbourne by 74 per cent and Sydney by 54 per cent.

The Royal Australian Institute of Architects has urged governments to tackle the sprawl by clamping down on new fringe suburbs and focusing instead on higher population densities in inner and middle suburbs.

In South Australia, the cost of providing new outer-city suburbs with power, water, sewerage, schools, hospitals and local government services has been estimated at A$85 million (nearly $110 million) for every 1000 new homes.

In Queensland, Premier Anna Bligh last year proposed new curbs on Brisbane's expanding borders.

Severe congestion and shortage of services also fuelled anger in crucial western Sydney seats against Prime Minister Julia Gillard during last year's election.

The Labour Studies Institute report, prepared for the Department of Immigration and Citizenship, said higher levels of net overseas migration meant greater adverse impacts on both natural and developed environments.

It warned of increasing pressures on water supplies and quality, land use, food production, air pollution, greenhouse gas emissions, traffic congestion and transport infrastructure.

The report said that if there was no migration Australia's big cities would still expand by up to 50 per cent, and at present rates of immigration they would balloon by up to 150 per cent.

Bigger cities would drive up demand for oil, but as demand grew Australia's domestic production would rapidly diminish at a time when the availability and price of foreign supplies were under pressure.

"The outlook for oil is particularly grim for transport oil," the report said.

ON THE WEB

Long-term physical implications of net overseas migration: Australia in 2050, immi.gov.au