But years of drought, which some blame on global warming, have savagely depleted the huge dams built 60 years ago to hold the snow melt from the Australian alps and push it hundreds of kilometers inland to the parched west for farm irrigation.

The Murray-Darling normally provides 90 percent of Australia's irrigated crops and A$22 billion ($18.1 billion) worth of agricultural exports to Asia and the Middle East.

Murray-Darling Basin.

But with some crops now just 10 days from failure, farmers are to receive no water at all for irrigation through the summer, while others will get a fraction of their regular entitlement to keep alive vital plantings like citrus trees and grapevines.

A thin winter green carpets Australia's southeast hills and plains, camouflaging the onset of a drought catastrophe in the nation's food bowl.

Sheep and cattle farmer Ian Shippen stands in a dying ankle-high oat crop under a mobile irrigation boom stretching nearly half-a-kilometer, but now useless without water.

"I honestly think we're stuffed," he says grimly.

"It's on a knife edge and if it doesn't rain in the next couple of weeks it's going to be very ugly. People will be walking off the land, going broke."

Shippen's property "Chah Singh" sits in the heart of Australia's Murray-Darling river basin, a vast plain bigger than France and Germany, home to 2 million people and in good times the source of almost half the nation's fruit and cereal crop.

©Michael Bell, Murray-Darling Basin Commission
The mouth of the River Murray in South Australia.

The massive Hume Weir, which can hold enough water to fill seven Sydney Harbours, is so dry that a lakeside holiday village is now half-a-kilometer from the depleted shore and rods to measure water depth stand on bare rock far from the waters' edge.

"It's grim. The water is not there," says Wendy Craik, the head of the Murray-Darling Basin Commission which oversees storage in the country's longest river and dam system.


Australia's Prime Minister John Howard warned of an "unprecedentedly dangerous" drought in April and advised the nation to pray for rain as economists warned the dry would wipe one percent off the A$940 billion economy in 2006-07.

Those prayers were answered briefly in May and June after winter storms lashed the east coast and major cities, bringing localized flooding and seemingly the end of a dry spell which has lasted near a decade in some areas of the country.

But by bringing hope, the rains ironically may have also worsened the drought's impact on battling farmers through the hot months ahead.

"We thought it was just going to keep on raining. When you go into drought people normally just lock up and don't spend, but after that rain everyone just went out and spent money to plant crops and climb out of the hole they were in," says Shippen.

Near the town of Griffith in the Murrumbidgee River valley, renowned for its citrus and wines, thousands of oranges lie rotting under rows of trees stretching to the horizon under relentless blue skies.

"We are in the lap of the gods and rainfall. The trees are under a great deal of stress and any adverse weather or hot weather is creating an enormous amount of fruit drop," says second generation citrus grower Louis Sartor.

Sartor's father Giulio was among the Italian immigrant pioneers who opened Griffith to farming in the 1950s and he still works at age 80, pruning back trees against the drought.

"He thinks it will pass. He came here from Italy when it was like going to the moon. He is the total optimist," says the nuggety Sartor over tea and biscuits in his still-leafy garden.


Sartor, like many conservative Australian farmers, is deeply skeptical about climate shift's role in the drought, despite a UN Intergovernmental Panel on Climate Change predictions that temperatures could rise by 6.7 degrees Celsius by century's end.

"Find me the scientist that can stand up on a platform and say 'I know'," he says.

That skepticism runs even deeper south along the Murray, with many farmers certain irrigation shortages are the result of government bungling and a determination to claw back precious water for a green agenda driven by majority city-dwellers.

"I class this as a human-induced crisis, not a climate induced one," says Neil Eagle, 79, a fourth-generation citrus grower at Barham, a retirement and farming haven on the Murray.

Eagle's forebears settled this so-called "Golden Rivers Country" in the 1890s, bringing paddleboats into the area and opening up irrigated cropping in a region verging on desert.

"I believe it was warmer in the 1930s and 40s than it has been in the last 50 years. These things are cyclical," he says.

At the same time environmental scientists like Australian of the Year Tim Flannery argue the continent is a "harbinger" of climate shift and experiencing accelerated greenhouse warming.

They want to pipe the open irrigation ditches carved laser-straight across the landscape and cut back water use by 1,500 gigaliters to protect long-term river health.

"If we are going to devastate the regions for agricultural production, that's exactly what will do it," says a frustrated Eagle. "If that sort of insanity does not prevail, there's no reason we won't get good years again."


But dairy farmer Phil O'Neill, who faces ruin with his critical water allocations cut, suspects climate change may be a part of what some say is the worst drought for a century.

"I'm a bit of a believer. This weather change combined with cyclical downturn in rains, it's a bloody disaster," he says.

O'Neill, a stocky 49-year-old with huge hands and steel-wool hair, is one of the last dairy farmers near Barham, with the long dry having already forced most others off the land.

With a rueful smile he says he spent A$300,000 to keep going through last summer and wont be doing it again, instead opting to sell off parts of his cherished 1,100 acre farm.

"There is 30-40 years of breeding there and it could all be gone soon," he says, his voice cracking with emotion as he hefts three-day-old calves onto pickup truck for sale or slaughter.


George Warne, the head of Murray Irrigation, lives in Barham and is training staff to spot depression in farmers as the drought hits harder.

"There's an underlying epidemic of fear and worry out there," he says. "We've got all the signs of a stressed community."

Reserve Bank figures show rural debt has risen sharply from A$26 billion in 1999 to A$43 billion in 2005. "We are hearing stories of farmers defaulting on lease payments," Warne says.

Adding to the economic vice are rising interest rates, with most farmers already heavily in debt for millions of dollars worth of tractors, harvesters and irrigation equipment.

Warne backs a A$10 billion plan put forward by Prime Minister Howard to protect water supplies in the months ahead, but which is being whittled back by bickering between competing states over water. Howard wants to seize control of the river system to end state squabbling and make water a nationally-controlled asset.

Shippen says the drought and a new sense of the importance of water in the driest inhabited continent, with prices having gone from A$30 a megaliter to hover near A$800, will change Australian farming forever and make some irrigation unviable.

"It's going to be a massive change," the one-time rice farmer says. "I spent the first half of my life developing irrigation and I'll spend the second half pulling it down."

To Warne the only solution to a disaster threatening to unravel whole rural communities is in the heavens.

"We are now in something that is beyond probabilities. We are in a drought sequence that's worse than our white history," he says.