Dam it, farm it (Image: Getty)

The government wants to dam northern rivers to create a giant food bowl – but no one knows how it will effect the environment or Indigenous people

AUSTRALIA has a daring plan: to convert its tropical north into a huge “food bowl”. The area being considered spans 3 million square kilometres. The plan offers many benefits, but the environmental risk has not yet been properly measured and may be huge.

Developing the north is a major aim of the Liberal party governing Australia. They want to double the country’s agricultural output by mid-century. In a policy paper last June, they said: “No longer will northern Australia be seen as the last frontier: it is in fact, the next frontier.” They are now preparing a white paper.


At first glance, north Australia is promising. It gets 1 quadrillion litres of rain a year. Most falls in just four months, so the idea is to build dams to store these wet season rains, and irrigate the land during the eight bone-dry months.

There is clearly potential, says Peter Stone of the CSIRO in Brisbane. Aquifers alone could sustain 60,000 hectares of crops, according to a 2009 report. Then there are the rivers. Dams on just two, the Flinders and Gilbert, could support 50,000 hectares of crops, according to a study by Stone in December.

Stone says 1.7 million hectares could conceivably be irrigated. But he says the government will probably miss its target. “I’d be surprised if we could double Australia’s agricultural output.”

A key problem is that most of the rain evaporates fast, so only 20 per cent or so enters rivers. “If you took all of that, then there would be zero stream flow,” Stone says. Perhaps only 1 per cent would be available for irrigation.

The variable climate makes things even riskier. Yearly rainfall can be half or twice the average.

Then there are the downsides. Northern Australia contains 25 per cent of the world’s tropical savannahs – the only significant area in a wealthy, stable country. Each wet season, rivers overflow and flood the savannah, and life blooms. The region is home to 40 per cent of Australia’s reptiles and 75 per cent of its freshwater fish, says the Wilderness Society.

This environment will suffer if it is farmed. Yet the government wants to relax environmental regulations – to cut the “green tape”. Prime Minister Tony Abbott has said Australia needs to throw away “green extremism“.

The trouble is, the “wasted” rain is all used somewhere, such as supporting fisheries. For example, damming the Gilbert river would cut the water flow to nearby wetlands by 10 per cent.

We don’t know how these pros and cons will add up, says Michael Douglas of Charles Darwin University in Darwin, Australia. “We couldn’t tell you exactly how much you can take out before you start to degrade fisheries or reduce the number of turtles that Aboriginal people harvest.”

We can’t tell you how much you can take out before you degrade fisheries or reduce the turtle harvest

One thing’s for sure: Australia won’t get something for nothing.

Geese ate the seedlings, crocodiles threatened workers and the rice that did grow was too far from markets

Invading the north? An Indigenous Australian carries a wallaby back to camp (Image: Justin McManus/Fairfax Media) Everyone acknowledges, at least in principle, that the development of northern Australia must benefit Indigenous Australians. They already own 30 per cent of the land and claim land rights over 80 per cent. They are concentrated in the north, where they make up 16 per cent of the population, despite being only 2 per cent of the country’s total. Indigenous Australians have been enormously disadvantaged since the arrival of Europeans. Their life expectancy is 12 years shorter, and they are incarcerated 12 times as often as other Australians. They only got the right to vote in 1962. For the government, redressing the balance means “creating opportunities through education and economic development“. The trouble is, Indigenous Australians may not benefit from those opportunities, says Natalie Stoeckl of James Cook University in Townsville. Her research suggests they have less to gain from development than non-Indigenous people, and more to lose. They have few connections to the economy, so are unlikely to get jobs. Moreover, some Indigenous people rely on harvesting wild plants and animals, and irrigating crops threatens that (Biological Conservation, doi.org/tj2). Nevertheless, some Indigenous groups have expressed support for developing the north so long as their interests are prioritised. Stoeckl says this is essential. “New ‘developments’ need to forge strong financial links with existing residents, Indigenous and non-Indigenous,” she says. “Otherwise, the ‘development’ will be similar to what the Europeans did when conquering the new world.”

Lost in the Fogg No-frills response: the lizard is one of many species in the park (Image: Superstock) Fogg dam is an object lesson in how not to develop northern Australia. It was a gung-ho attempt to create a food bowl, one that unequivocally failed. The dam was built in 1956 to support rice farms. But the project flopped for all the reasons that are now recognised as problems in developing the region. Native wildlife like magpie geese ate the seedlings, crocodiles were a risk to workers, and the little rice that did grow was far away from markets. One story illustrates how badly wrong Fogg dam went. After the dam was built, it took eight years to build the channels for irrigation – because the flood plain was too wet for bulldozers. Instead of a big farm, the region is now a wildlife park, home to animals like frilled lizards, and a reptile and amphibian research lab.

Success, sort of (Image: Alamy) The Ord river scheme shows how developing Australia’s north will go: a partial success at best. It is the country’s largest dam and artificial lake. The main dam (above) was completed in 1972. Some hate it. The Wilderness Society says it “should serve as a clear and costly reminder of the development model we should not follow in the future“. They point out that food crops, mostly rice and sugar, failed. They have been replaced with sandalwood. Worse, 42 years on, the dam still hasn’t made back its cost. Others see it is a clear win. Ex-prime minister Kevin Rudd stood on the dam when he announced plans to further develop the area. In truth it is a fairly typical new irrigation project, says Peter Stone from the CSIRO in Brisbane. After lots of trial and error, it is finally working out. He says there is nothing wrong with growing sandalwood if there is demand. “It’s not my business what farmers grow.”

The right sort of dam The Flinders and Gilbert rivers are right next door to each other but they are strikingly different in their physical characteristics. The Gilbert would be suited to a large in-stream dam, while the Flinders could only support lots of small off-stream dams, according to a 2013 study. Like many of Australia’s northern rivers, they support massive flood plains in most wet seasons and shrink to trickles in the dry season. Together, they could support about 50,000 hectares of irrigated land in about 85 per cent of years. From an ecological point of view, in-stream dams are much worse, says Michael Douglas of Charles Darwin University in Darwin, Australia. Many fish, especially in the rivers that feed into the Gulf of Carpentaria such as the Flinders and Gilbert, need to move up and down the rivers. They can’t do that if there is a dam in the way.

Not visionary but useful The Burdekin dam supports the largest irrigated area in northern Australia: 80,000 hectares, mostly growing sugar cane. The water comes from a combination of surface water and groundwater. Some of the water from the dam is used to top up the groundwater, preserving it for the long term. Further developing the Burdekin is an obvious thing to do, but probably not as attractive to politicians who want to present their ideas as “visionary”, says ecologist Damien Burrows of James Cook University in Queensland. “The Burdekin is underutilised,” he says. “It has spare water and there’s spare soil downstream.” Even The Wilderness Society agrees. They say further developing existing, proven farmlands, rather than moving to risky greenfield sites, is a no-brainer.

This article appeared in print under the headline “The taming of a vast wilderness”