Abbott shows green credentials as he puts pressure on Rudd

Opposition leader Tony Abbott is thrusting the environment to the centre of this year's federal election campaign, gaining Greens support for the first time as two state Labor governments fall out over supplies of water from the Murray Darling Basin.

Abbott, a climate change sceptic who ousted predecessor Malcolm Turnbull over the former leader's support for the Government's greenhouse emissions trading scheme, is turning his focus away from global concerns to local problems of immediate concern to voters.

Central to this is the Murray Darling Basin, the vast river system that stretches almost 3400km down eastern Australia, supporting the bulk of the nation's agriculture and its biggest cities and towns.

The basin is in deep crisis, with its waters afflicted by salination and pollution, their flow dehydrated by overuse and years of drought, and the crucial wetlands at its mouth facing extinction.

Abbott has proposed a climate change policy that avoids an ETS - which remains blocked in the Senate - and aims instead at reducing carbon emissions through fuel efficiencies and land management. While this approach was heavily criticised, a dispute between New South Wales and South Australia over the renewed flow of water down the Murray River from recent heavy flooding has given him the traction he needs for his "backyard first" approach to the environment.

The basin has long been bitterly disputed between the eastern states, whose control over the portion that runs through their jurisdictions is protected by the Constitution.

This gives each the power to block and store whatever it requires - traditionally leaving South Australia, at the river's end, with a trickle of relatively low quality.

Prime Minister Kevin Rudd brokered a federal approach that he claimed would bypass states' rights and manage the entire basin in the national interest, but which has failed at its first real test. The floods pumped an estimated 500 gigalitres of water into the basin, almost all of it immediately earmarked by NSW for its storage systems, which can accumulate 640 gigalitres before federal control is triggered.

The move was greeted with fury by SA, Victoria and Canberra, and by water managers who warned that the Murray needed an urgent boost to its flow, especially for the threatened Coorong Lakes, the internationally recognised wetlands at the river's mouth.

NSW finally relented, this week agreeing to release some of the water to SA.

But the dispute allowed Abbott to pitch his new green credentials, slamming the Government for its failure to effectively manage the basin and promising new federal action if the Opposition wins power this year.

"Australia's biggest environmental problem is reconciling the human, economic and environmental demands on the Murray-Darling, where low environmental flows are having an impact on wildlife and wetlands," he said in a speech to the Sydney Institute.

"The basin provides a third of Australia's food supply and much of our agricultural exports.

"The millions of Australians living in its catchment largely depend on its rivers for their livelihoods and even drinking water."

Abbott said if elected he would seek a new agreement on the basin's management with the states and, if no agreement was reached by mid-2012, he would put the issue to a constitutional referendum the following year.

The proposal - and another calling for the creation of a "green army" of about 15,000 members to work on local environmental problems - was welcomed by the Greens, whose preferences Abbott is actively seeking.

Although a new Morgan poll, the first of the year, reported that support for the Opposition had nudged up 2 per cent over the holiday period, the Government still has a commanding 14-point lead.

Abbot wants green votes and believes the environment will be a vote-changing issue this election.

"It's high time the green movement rethought its habitual preference for Labor," he said.

"Actual improvements are more likely to come from conservative governments than Labor ones, which have a tendency to lock up land without maintaining it."