The former Australian of the Year, environmentalist Tim Flannery, is worried what effects a growing population will have on the environment.

South-east Queensland is a region where population pressures are at their greatest, with 2,000 people moving into the area each week. Some are from interstate, others from overseas.

Queensland's population is set to double within 50 years.

Professor Flannery says no-one has any real idea of the environmental effects of population growth and it is time for an independent inquiry to look at the issue.

"I'm pretty aware that we live in a fragile country with limited water availability, with a significant biodiversity crisis, a limited capacity to feed ourselves because our agriculture is under increasing stress from climate change," he said.

"And what I see is a government-set program for immigration, which really seeks to increase our population very quickly but without any proper analysis of the environmental impacts or indeed the social impacts of that program."

Finance Minister Lindsay Tanner has weighed into the population debate, saying it is laughable to argue Australia has too many people at this early stage.

He says Bangladesh is roughly twice the size of Tasmania but has seven times the population of Australia.

Professor Flannery says that is a meaningless comparison.

"Antarctica is bigger than Australia and it hasn't got any people at all, size isn't everything," he said.

"Lindsay Tanner may well be right but we need the figures. We need the analysis to understand what we can do in terms of a sustainable population living at this standard of living.

"It's all very well to wave your hands in the air and say everything's going to be okay, but show me the data, that's what we actually need.

"At the moment ... all of our population-related policies, such as immigration and rebates for children, all that sort of stuff are just happening in a vacuum and that's not good enough."

'Growth manageable'

Premier Anna Bligh says Queensland can handle the projected population growth.

"I think this growth is manageable but it does have to be managed, we can't let it happen unchecked and we can't let it happen without a plan," she said.

"What's interesting living in a federation and governing at a state level is that some of the levers on population are often beyond your control but the consequences all fall into your basket.

"Some of the levers, such as immigration policy, things like the baby bonus, have consequences and state governments end up having to manage some of those consequences.

"It does require serious and careful thinking and serious and careful planning and some very serious infrastructure that does I think need partnership from all levels of government."

Ms Bligh says she agrees with the current immigration levels but says there is scope for better planning between state and federal governments about where the new Australian population should be concentrated.

And she says more debate is needed on the issue of sustainability, environment and resources.

"Over the last five years, as we've put together our south-east Queensland plan which is a statutory plan to manage growth, there has been a wide consensus about the need to restrict growth and not let it go in to big urban sprawls," she said.

"But as the rubber hits the road on making decisions about higher density in people's neighbourhoods, the community I think is becoming less settled about that. "They're very alarmed by the prospect that they'll see a lot of high rises and concerned about the character of their neighbourhoods and their communities changing and changing too rapidly."

Professor Flannery concedes population growth is needed to grow the economy but he says it's vital to get the balance right.

"The economy will always need more people, business will always need more customers, government will always need more taxpayers," he said.

"That's not a valid argument for eternal growth. We all know there are limits to growth and we need to work out how to grow our population, if that's what's required, at the appropriate level over the appropriate time scale.

"To do that you've just got to really look at proper triple-bottom-line accounting and the Government's always getting onto businesses about doing triple-bottom-line accounting, well it's time the Government did it itself.

"Our environment, social and economic outcomes all have to be fed into these very important policies that will change our country in the long term, change it forever. You can't really wind back population once you've built it in."