Going, going, ... gone
Australia is a country endowed with abundant natural resources. It has also become the first First World society to feel the limits of those resources.
In the past five years, Australia’s five southern mainland capitals have awoken to the frightening possibility that they could run completely out of water – not in some virtual future that can be planned for, but shockingly soon. For the two million people of greater Brisbane and its extended satellite populations, even under the severest water restrictions, their water supply is set to run out in 2009.
The nation’s 2.5 million hectares of irrigation developments, a core part of a sophisticated agricultural system that allows Australia – population 21 million – to produce enough food for 70 million people, have already run completely dry. Some irrigated farms, with millions of dollars invested in infrastructure, have had little or no water allocation for the past three years.
Even the nation’s ecological systems, evolved to handle the vagaries of life on the continent with the world’s most variable rainfall, are failing. Nature can readily handle the long sequence of drought years that have desiccated the landscape, but not when they come on top of the ecological alterations and water diversions that modern Australians have thrown into the equation.
The good news is that human fallibility is part of the problem. Much of Australia’s current water crisis is a consequence of poor, or at best optimistic, decision-making. But over-allocated irrigation licences can be bought back, leaking pipes replaced and water usage habits changed.
The bad news is that a dramatic downturn in rainfall since 2001 has exposed these human failings. And in a warming world, there’s no guarantee that the rain will return to the more comfortable levels of the past.
Drought and flooding rains
Australia has one of the most variable climates in the world. Not for nothing did poet Dorethea McKellar write of ‘A land of drought and flooding rains’. On a so-called co-efficient index, the variability of Australia’s rainfall is about 17 per cent. On the same scale, the variability of rainfall in the UK is under eight per cent, and for the USA, it’s about five per cent.
A case study of what this means in practice can be seen in the 467-kilometre Hunter River, which drains a fertile valley about two hours drive north of Sydney. In June, the river burst its banks, killing nine people. A few days earlier, it had been barely trickling – the river’s typical state since 2002. On a scale of variability between maximum and minimum annual flows, the Hunter comes in at a chart-topping 54.3. By comparison, China’s Yangtze River scores a two and the Rhine in Switzerland scores 1.9.
Australia’s climate variability comes in different cycles, beginning with the daily west–east advance of atmospheric systems and seasonal variations, and moving into inter-annual patterns related to warming and cooling of the Pacific Ocean. But climatologists are now talking of another cycle: ‘climate shift’. It’s spelled out in the rainfall falling across the catchments of four Sydney dams, including the city’s main dam, Warragamba. Between 1909 and 1948, the average annual rainfall across this area was 780 millimetres, with calculated dam inflows of 892 gigalitres. A climate shift then appears to have occurred between 1949 and 1990, when annual rainfall leapt to 907 millimetres and inflows to just over 2,000 gigalitres.
Since 1991, however, average annual rainfall has slumped to 681 millimetres, and inflows to 572 gigalitres. Modern Sydney uses about 600 gigalitres of water a year.
Here, in a nutshell, says New South Wales natural resources commissioner Dr John Williams, is Sydney’s current water crisis. ‘From the 1950s to the mid-1990s, we had some dry sequences, but the underlying trend was much wetter than the first half of the century,’ he says. ‘That was the period when Sydney’s population grew from about a million to more than four million, and we put in all our major infrastructure. We may have overstressed the system based on decisions made during a wet period.’
The continent as a whole shows a similar pattern. National Climate Centre data suggest that average rainfall across the landmass was 477 millimetres between 1900 and 1946, rising to 573 millimetres between 1947 and 2000. Since 2001, the average has fallen to 484 millimetres. The UK has an average annual rainfall of 1,100 millimetres.
What the broad continental statistics don’t reveal is that the sharp 21st-century drop in rainfall has occurred mainly in the continent’s lower third and its far east, home to its major population centres and its most productive agriculture. In the north and northwest, which is dominated by sparsely populated cattle stations, annual rainfall appears to be steadily rising.
For most of the continent, it’s too early to say whether this trend is a climatic hiccup or harbinger of a climate change future; not so in southwest Western Australia. During the 1970s, says Dr David Jones, head of climate analysis at the Bureau of Meteorology, average annual rainfall in southwest Western Australia dropped by ten per cent. Now the charts are suggesting that over the following 30 years, rainfall slid another ten per cent.
‘When the first decline occurred, river flows dropped by up to 50 per cent, give or take a bit, and with the subsequent decline the flow situation is even worse,’ Jones says. ‘There is now a clear mismatch between past expectations of how much surface water was available in Western Australia and the current reality.’
The drying of southwest Western Australia fits neatly with computer modelling of the effects of climate change on Australia, Jones observes, ‘only the models might have underdone the severity of the change’.
In the northwest, in places such as the Great Sandy Desert, rainfall has increased by 25–50 per cent over the past 30 years. ‘We don’t know why,’ Jones says, ‘but again, the general suspicion is that it’s climate change.’
For southeast Australia, the links between disappearing rain and global climate change – or any other discernable climatic pattern – are less clear. What is clear is a warming trend. In 1980, Australia experienced the highest average continental temperatures on record. In 1998, that record was broken by 0.1°C. In 2005, the ’98 record was itself broken, by 0.3°C. The first five months of this year have been a whopping 1.6°C above the last record average maximum for the period, set in 1981. ‘It’s taken 25 years to break the record, but now it’s broken, we’ve smashed it,’ says Jones.
Drawing a trend line across the temperature graph indicates that the continent as a whole is warming by about 0.2°C per decade.
It’s highly likely that there is a link between this warming trend and rainfall decline. ‘Statistically, rainfall over the past ten years has been unlike any other decade over the past century,’ says Jones. ‘It would be foolish to suppose that it’s unrelated to climate change… but we dearly hope not.’
Australia’s breadbasket
The impact of rainfall declines on rivers and streams isn’t linear. A millimetre of rain doesn’t mean a dam gains by the equivalent amount. Because bone-dry soil needs to become sodden before runoff occurs, every ten per cent decline in rainfall can mean a five-fold decrease in stream flows.
In the Murray–Darling Basin (MDB), the 1.06-million-square-kilometre catchment of the 2,740-kilometre Darling and the 2,530-kilometre Murray rivers – and 21 other major rivers – this century’s drying has already had profound consequences for the region described as Australia’s breadbasket.
About half of Australia’s croplands – 11 million hectares – are in the basin. The catchment also generates a third of the nation’s beef cattle production, two thirds of its dairy production, and about 15 per cent of its wool and sheep meat.
About three quarters of Australia’s 2.5 million hectares of irrigated land is also in the MDB – except that this year, no surface water is available. On 1 July, the Australian government turned the taps off to the three quarters of the basin’s irrigators who rely on surface water. (The remainder draw on groundwater, also a dwindling resource.) Most of the basin’s 200 large water storages had been drawn down to critical levels by the middle of this year.
The Darling River, Australia’s longest, drains the flat, semi-arid inland of Queensland and New South Wales. It’s certainly no stranger to desiccation: it stopped flowing 48 times between 1885 and 1960.
In 2002, after prolonged drought, even formerly permanent water holes began to dry up. Collectors were able to walk the beds of billabongs and pick up the bottles thrown overboard from paddle steamers that plied the river during Queen Victoria’s reign. Despite some small flows since, today, the river is a sandy gutter cutting through Australia’s inland.
The Murray, whose upper-stream waters come largely from snow melt at its headwaters in the Australian Alps, is regulated by a hydro-electricity scheme built in the 1950s. Even though it retains the appearance of a river, it too is in trouble. The major dams that deliver much of its water are currently at little more than ten per cent of their capacity. Most of the dams in smaller valleys throughout the basin are in even worse shape.
Over years of floods and droughts, the mean annual discharge of the Murray–Darling system is 10,090 gigalitres. In 2004–05, towns and irrigators used about 11,000 gigalitres from the catchment under licence. The disparity between water extractions and average long-term flows hasn’t been lost on governments, which set a formal ‘cap’ on extractions in 1995. More than a decade of talking later, however, little real progress has been made on removing the anomaly.
The body charged with managing the basin’s resources, the Murray-Darling Basin Commission, warns that things are unlikely to get better. It says that estimates of the effect of climate change on the basin suggest a 5–10 per cent decrease in rainfall in the northern, summer-dominant rainfall areas, and a larger 10–20 per cent decrease in the south – with corresponding reductions in stream flows.
Stressed systems
If the humans who depend on the rivers are feeling the effects of drought, the rivers are feeling it more. In a 2000 national audit, about a third of Australia’s rivers were classified as being in ‘extremely poor condition’, and the situation has since been exacerbated by drought.
The curlew sandpiper and the red-necked stint are in decline on the Coorong, a 50,000-hectare coastal wetland system in South Australia that was once fed by the interplay between the Murray and the tidal flows at its mouth. Pelicans no longer breed there. Brine shrimp are on the increase, however, as the water at the lower end of the system becomes saltier, and the shrimp-loving Australian banded stilt has followed.
Flows into the Coorong have been in decline for 20 years; for the past four, there have been no inflows into the wetlands at all. Leading freshwater ecologist Professor Peter Cullen believes the wetland may be doomed unless thinking about ecological management of water changes.
‘Australian aquatic ecosystems are adapted to drought, but between natural drought and man-made drought we’ve stressed systems beyond their normal capacity,’ Cullen says. ‘We have to rethink the way we manage the ecosystem. In the past, for instance, animals and plants in rivers survived drought by sheltering in deep pools. We’ve put in weirs so animals can’t get to the pools, and people are pumping out the pools for stock water.’
In some parts of the lower Murray, up to three quarters of the river red gums that line the river, or form floodplain woodlands such as the 66,000-hectare Barmah-Millewa Forest, are considered to be dying or stressed. That means much more than a loss of centuries-old eucalypts and some fine scenery, according to Professor Sam Lake of Monash University.
‘Red gums drop their leaves into streams, where they are then eaten by microbes,’ Lake says. ‘The microbes are, in turn, food for invertebrates, which are eaten by vertebrates such as fish. The red gums are a major driver of river health.’
In addition, periodic flooding in the Murray-Darling Basin’s rivers – and elsewhere in Australia – is necessary to trigger bursts of floodplain plant growth and animal breeding that pour organic nutrients back into waterways. In full swing, Lake says, floodplains are some of the world’s most productive ecosystems.
Dams and water extractions have tamed many of these flooding ecosystems, including those of the Murray. In belated recognition of the needs of flood-reliant environments, governments have, in recent years, legislated ‘environmental flows’ from some dams. In the case of the Murray, this has seen dam releases of up to 500 gigalitres at a time to replicate the sudden excesses of unregulated history. Lake acknowledges the good that this has delivered to environments such as the Barmah-Millewa Forest, but observes that it isn’t enough.
‘Environmental flows were designed to turn on river processes, but we also need flows to turn on wetlands if we’re to keep the rivers alive,’ Lake says. ‘It seems likely that we’re in for an extensive period of drying in southeastern Australia. We may have to quarantine environmental water, and take total control of how we use it if we want to keep our river environments.’
Imaginary distinctions
At the other end of nature’s spectrum, Australia’s urban dwellers have been quarantined from the effects of drought by the big infrastructure developments that began after the Second World War. But in the past few years, the imaginary distinctions between urban life and the natural world have crumbled.
For the nearly two million people living in southeast Queensland – in Brisbane, the Gold Coast and ten surrounding councils – the practical effects of too little water for too many people meant that from early April, people and businesses were only able to ‘water their gardens with buckets three times a week in the evenings’. The ‘Level 5’ water restrictions are aimed at bringing water use down to less than 140 litres per person per day. A month after the restrictions were introduced, the population was still using 152 litres per head per day – albeit an improvement on the 190 litres per head per day it consumed in wetter times.
Summer rains have already failed the region four years in succession. Dam levels are, on average, below 20 per cent, and water authorities warn that even if the target usage is met, dams will be at less than five per cent capacity within two years if no heavy rain is forthcoming.
Last year, in a race against the clock, the Queensland government announced a AU$1.7billion (£700million), 200-kilometre pipeline to take treated recycled sewage from the city and nearby Ipswich to two coal-fired power stations and, in a worst-case scenario, the city’s main water storage, Wivenhoe Dam. Construction is well underway in what is supposed to be a three-year project, but critics argue that the project is too little, a decade too late.
Perth, the world’s most remote city, realised it faced a water crisis several years ago. It wasn’t a difficult conclusion: the city’s catchments now yield half the water they did 30 years ago due to declining rainfall. The Western Australian capital draws half its water from dams, half from underground aquifers that are being inadequately recharged by diminishing rainfall.
The West Australian government responded by sinking new bores into the layered aquifers beneath the city, planning two small new dams – and commissioning a desalination plant, the country’s first. The reverse osmosis plant will eventually deliver up to 45 gigalitres a year – 17 per cent of the city’s water requirements. In a nice ‘green’ touch, the plant will be powered entirely by a wind-generation installation north of the city. Earlier this year, the government announced the commissioning of a second desalination plant, also powered by renewable energy, which will initially deliver another 45 gigalitres a year, but will have the capacity to produce 100 gigalitres. ‘We can no longer rely on traditional, seasonal climate patterns and rainfall,’ said the state’s premier, Alan Carpenter.
The Victorian government has reached the same conclusion. The parlous state of the water supply for Melbourne, the Victorian capital, was underlined earlier this year when Melbourne Water hailed a rise of a mere 0.1 per cent in its storages as good news: ‘The first time storages have risen by more than 1,600 million litres in one day since December 2005’. The inflow brought the city’s storages to 28.5 per cent full, compared to 48.3 per cent at the same time the previous year.
Confronting the grim water outlook, in June, the Victorian government announced a AU$4.9billion package to restore a reliable water supply to the state capital and its agricultural sector. Among the measures is a major desalination plant, one of the world’s largest, with the capacity to convert 150 gigalitres of seawater to potable water each year; 250 kilometres of pipeline to expand the Victorian water grid and make water more easily transferable between towns; and modernisation of irrigation infrastructure in the state’s north to prevent ‘leaks, evaporation and inefficiencies’ that will ultimately, the government hopes, deliver an extra 450 gigalitres of water a year.
The New South Wales government is moving in step. After announcing plans for a desalination plant in 2005, in June, the government doubled the specifications, announcing that the plant would be capable of producing 250 megalitres per day, ‘effectively drought-proofing the city’, according to the premier, Morris Iemma. The plant is due to be completed by 2010.
Sydney’s network of 11 dams sank to just a third of their combined 2,584 gigalitre capacity in February, but good rains throughout the catchment kicked the city out of immediate danger by mid-year, boosting capacity to 50 per cent.
In April, Adelaide’s authorities refuted media reports that it was 40 days away from running dry, saying that the city’s Murray River storages were at 56 per cent of capacity, giving the city eight months of water if there are no other inflows. The city is uniquely reliant on the stressed Murray-Darling system for its water. Good snowfalls in the Australian Alps promise a snowmelt flush down the Murray next spring, but by mid-year, the storages and rivers in the basin had received little benefit from promising autumn rains. Consequently, Adelaide, although less wealthy than mining-rich Perth, is also considering the desalination option.
Low-hanging fruit
Desalination is a relatively quick and workable answer to an urban water crisis, but like the sudden push for domestic rainwater tanks by local councils, it’s the low-hanging fruit in a whole tree full of tricky water-related questions that are casting a shadow over Australia’s future.
‘The way we do irrigated agriculture will have to be rethought; how we provide water to cities will have to be rethought,’ says NSW Natural Resources Commissioner John Williams. ‘We’ve avoided these questions for years, but out of necessity, we now have to consider major reforms.’
The possible changes are many. Lifestyle looms large among them. Australians are profligate users of water. A global study published this year ranked the water ‘footprint’ of each Australian at 341,000 litres a year – easily the world’s highest. English-style gardens and swimming pools are two inappropriate Australian enthusiasms that may have to be modified in a drier climate.
Australia’s 2.5 million hectares of irrigation will also have to be revisited. Part of the solution lies in plugging leaks and stopping the evaporation inherent in the open-channel system. If that proves inadequate, however, governments will have to bite harder and start buying back irrigation licences – forcefully. A voluntary buyback system now in place has pulled in only a fraction of the licences that must be decommissioned if water security is to be secured in over-committed catchments such as the Murray–Darling.
The nature of the crops grown under irrigation will also have to change. Cotton production used 1,821 gigalitres of water in 2004–05, dairy farming used 2,275 gigalitres, sugar 1,270 gigalitres and rice 630 gigalitres. As water becomes more scarce, and thus more valuable, low-return, water-hungry crops such as rice or even cotton may no longer be viable in Australia.
In urban areas, a national distaste for the notion of recycled water – the ‘yuk factor’ – is yet to be overcome. Sydney recycles only three per cent of its water, Melbourne ten per cent and Adelaide 20 per cent. Australian household water use amounted to 1,874 gigalitres in 2004–05; use of recycled water by households was just 1.3 gigalitres in the same year. Brisbane will have the ability to recycle drinking water when its new pipeline is completed, but politically, the yuk factor suggests that actually putting recycled water into Wivenhoe Dam will be a last resort.
Dam-building is also a political minefield. Following the successful campaign to halt the construction of the Franklin River dam in Tasmania in 1983, and with the environmental consequences of damming a major catchment better understood, governments have tended to stay away from dams out of self-preservation. Nor will a dam, which takes years to build and fill, resolve any current water crisis. Out of desperation, however, the Queensland government has flagged its intention to build two dams near Brisbane, and so far borne the subsequent political fallout.
Australia does, theoretically, have ample water for its current population. It’s just in the wrong place. Australia’s far north remains mostly undeveloped, but three of its vast catchments – the Timor, Gulf and North-Eastern – carry 60 per cent of the nation’s runoff during the monsoon season. The drought in the south, and increasing rainfall in the north, have revived ambitions to make use of this resource. Some plans involve piping the water south; others taking agriculture north. Both have serious limitations.
The West Australian government considered piping water to Perth from the huge Ord River dam in the Kimberley region, 3,300 kilometres to the north. However, the cost in infrastructure and energy to shift the water could, researchers have calculated, instead provide the city with 12 desalination plants.
A Federal taskforce is currently considering the costs and implications of opening up the north to more intensive agriculture, but the proposal faces a major obstacle. Most of the crops grown so productively in the south – cereals, oilseeds, frost-dependent horticultural crops – can’t be grown in the north’s harsh, hot climate. Cattle are able to live in the north, but the British-breed beef cattle and the dairy breeds that dominate in the south don’t perform well in these conditions.
Extreme challenges
Out of necessity, the political resolve to address Australia’s water challenges is firming. In 2004, the federal government created the National Water Initiative, a strategy to put water trading and policy on the same, market-driven basis across the country. This year, it took the extra step of taking water management away from state control and placing it under one national body. For the Murray–Darling Basin in particular, the move means that water flowing across four state boundaries is no longer subject to four different laws made in state interests.
Experienced scientists and observers recognise the extreme challenges that Australia faces, but believe that solutions can be delivered if the political will is behind them. Those solutions will have little to do with the past. ‘We simply no longer have historical benchmarks to use,’ says David Jones on climate change. ‘We have to shift from managing known risks, to managing unknown risks.’
That means, Cullen says, that Australians have to start building a ‘resilience framework’ into their cities, agriculture and ecosystems. ‘When you don’t know what’s confronting you, the ability of your systems to adapt to changing conditions is essential.’
The hidden water cost
People eat water – lots of it, embodied in our food. And in a country such as Australia, where meat is a central part of the diet, they eat even more. People also use water every time they flick the switch on an electrical outlet.
To run Australia’s current economy, taking into account factors such as exports and power generation, takes about 1.4 megalitres per person per year. Relatively little of that is drunk.
Barney Foran of the Australian National University in Canberra looked at figures for water consumption in affluent inner Sydney. Here, just ‘lifestyle’ use annually accounts for about 850,000 litres per person. About 44 per cent of that total is embodied in food, Foran says.
To put this in context, making a cup of coffee has been calculated to require 140 litres of embodied water. A litre of milk takes about 1,000 litres of water. A kilogram of rice takes 3,000 litres, and a kilogram of grain-fed beef takes 16,000 litres. Manufacturing a microchip requires 32 litres.
In Sydney’s inner suburbs, ‘having showers and watering the three pot plants we have out on the terrace and so on’ consumes another 20 per cent of ‘lifestyle’ water, Foran says. And then there’s the third of total water use that is hidden away in energy (13 per cent in Foran’s Sydney calculation) and services (20 per cent).
Foran’s response to these figures is to urge a ‘re-naturing’ of the Australian economy. ‘There has been a very concerted effort over the past 100 years of economics to take all environmental and resource implications out of what makes economic growth, and that is just not a valid way to go,’ he says. ‘Underpinning every dollar generated in this economy is an energy, a water and a land transaction, so we have to reintroduce a concept up-front that nature is well inculcated into.’
A better way of storing water
Fly over any part of closely settled Australia, and the reflection from farm dams winks back from all quarters. In warmer parts of the country, evaporation rates from such open storages approaches two metres a year.
There is a better way of storing water. ‘Aquifer storage and recovery’ (ASR) is a proven technology that involves injecting water into underground aquifers and then pumping it out when needed.
But, says hydrogeologist Dr Rick Evans of consultancy Sinclair Knight Mertz, Australia’s water is currently valued far to cheaply to make the solution viable. ‘In our gravity-fed irrigation areas, water is valued at AU$30 a megalitre – very, very cheap. A typical ASR scheme costs AU$500 a megalitre for water treatment, injection and extraction. Against current costs, the ASR method isn’t viable. But
if the real costs of surface-water infrastructure and loss were taken into account, ASR is actually cheaper.’
Australia is rapidly re-evaluating the real value of its water, and there is a small ASR scheme near Adelaide. But it’s likely that climate change will have to bite harder before ASR is picked up as a preferred water storage option. In the meantime, Evans wryly observes, ‘if we go out of our way to make dams that leak, we’re creating ASR schemes’.
Drought's depressing statistics
As this article went to press, the majority of drought-stricken eastern Australia was enjoying the best rain it had seen for years. For some farmers, however, green paddocks merely represented a chance to sell up in an up-beat market. Years of hand-feeding stock, a run of failed crops, or the inability to create mortgage repayments out of dust, have taken them to the end of the line. But perhaps not as dramatically as the media suggested in the height of the drought.
Last year, media outlets around the world reported that every four days, an Australian farmer committed suicide. It was a headline-grabbing figure, but it came from a decade-old report that actually cited a farmer suicide on average about every six days. Overall, Australian suicide figures have dropped about 20 per cent since the report was released, and some argue that rates among farmers have shown a similar decline – despite the drought.
There is no question that there has been some drought-induced suicide, although figures are unavailable. There have also been widespread reports of extreme depression among drought-stricken Australian farmers. But awareness campaigns on the dangers of depression, and greater willingness among men to be treated – although usually at the request of their wives – may have short-circuited the more extreme responses.
What remains to be seen is whether the rain brings down depression and suicide rates, or lifts them. Government forecaster the Australian Bureau of Agricultural and Resource Economics, reported earlier this year that average farm cash incomes for 2006–07 would be the lowest on record – AU$26,600, down from an estimated AU$81,290 in 2005–06. What the figure doesn’t reveal is the debt hole that many farmers will never climb out of.
August 2007
In the past five years, Australia’s five southern mainland capitals have awoken to the frightening possibility that they could run completely out of water – not in some virtual future that can be planned for, but shockingly soon. For the two million people of greater Brisbane and its extended satellite populations, even under the severest water restrictions, their water supply is set to run out in 2009.
The nation’s 2.5 million hectares of irrigation developments, a core part of a sophisticated agricultural system that allows Australia – population 21 million – to produce enough food for 70 million people, have already run completely dry. Some irrigated farms, with millions of dollars invested in infrastructure, have had little or no water allocation for the past three years.
Even the nation’s ecological systems, evolved to handle the vagaries of life on the continent with the world’s most variable rainfall, are failing. Nature can readily handle the long sequence of drought years that have desiccated the landscape, but not when they come on top of the ecological alterations and water diversions that modern Australians have thrown into the equation.
The good news is that human fallibility is part of the problem. Much of Australia’s current water crisis is a consequence of poor, or at best optimistic, decision-making. But over-allocated irrigation licences can be bought back, leaking pipes replaced and water usage habits changed.
The bad news is that a dramatic downturn in rainfall since 2001 has exposed these human failings. And in a warming world, there’s no guarantee that the rain will return to the more comfortable levels of the past.
Drought and flooding rains
Australia has one of the most variable climates in the world. Not for nothing did poet Dorethea McKellar write of ‘A land of drought and flooding rains’. On a so-called co-efficient index, the variability of Australia’s rainfall is about 17 per cent. On the same scale, the variability of rainfall in the UK is under eight per cent, and for the USA, it’s about five per cent.
A case study of what this means in practice can be seen in the 467-kilometre Hunter River, which drains a fertile valley about two hours drive north of Sydney. In June, the river burst its banks, killing nine people. A few days earlier, it had been barely trickling – the river’s typical state since 2002. On a scale of variability between maximum and minimum annual flows, the Hunter comes in at a chart-topping 54.3. By comparison, China’s Yangtze River scores a two and the Rhine in Switzerland scores 1.9.
Australia’s climate variability comes in different cycles, beginning with the daily west–east advance of atmospheric systems and seasonal variations, and moving into inter-annual patterns related to warming and cooling of the Pacific Ocean. But climatologists are now talking of another cycle: ‘climate shift’. It’s spelled out in the rainfall falling across the catchments of four Sydney dams, including the city’s main dam, Warragamba. Between 1909 and 1948, the average annual rainfall across this area was 780 millimetres, with calculated dam inflows of 892 gigalitres. A climate shift then appears to have occurred between 1949 and 1990, when annual rainfall leapt to 907 millimetres and inflows to just over 2,000 gigalitres.
Since 1991, however, average annual rainfall has slumped to 681 millimetres, and inflows to 572 gigalitres. Modern Sydney uses about 600 gigalitres of water a year.
Here, in a nutshell, says New South Wales natural resources commissioner Dr John Williams, is Sydney’s current water crisis. ‘From the 1950s to the mid-1990s, we had some dry sequences, but the underlying trend was much wetter than the first half of the century,’ he says. ‘That was the period when Sydney’s population grew from about a million to more than four million, and we put in all our major infrastructure. We may have overstressed the system based on decisions made during a wet period.’
The continent as a whole shows a similar pattern. National Climate Centre data suggest that average rainfall across the landmass was 477 millimetres between 1900 and 1946, rising to 573 millimetres between 1947 and 2000. Since 2001, the average has fallen to 484 millimetres. The UK has an average annual rainfall of 1,100 millimetres.
What the broad continental statistics don’t reveal is that the sharp 21st-century drop in rainfall has occurred mainly in the continent’s lower third and its far east, home to its major population centres and its most productive agriculture. In the north and northwest, which is dominated by sparsely populated cattle stations, annual rainfall appears to be steadily rising.
For most of the continent, it’s too early to say whether this trend is a climatic hiccup or harbinger of a climate change future; not so in southwest Western Australia. During the 1970s, says Dr David Jones, head of climate analysis at the Bureau of Meteorology, average annual rainfall in southwest Western Australia dropped by ten per cent. Now the charts are suggesting that over the following 30 years, rainfall slid another ten per cent.
‘When the first decline occurred, river flows dropped by up to 50 per cent, give or take a bit, and with the subsequent decline the flow situation is even worse,’ Jones says. ‘There is now a clear mismatch between past expectations of how much surface water was available in Western Australia and the current reality.’
The drying of southwest Western Australia fits neatly with computer modelling of the effects of climate change on Australia, Jones observes, ‘only the models might have underdone the severity of the change’.
In the northwest, in places such as the Great Sandy Desert, rainfall has increased by 25–50 per cent over the past 30 years. ‘We don’t know why,’ Jones says, ‘but again, the general suspicion is that it’s climate change.’
For southeast Australia, the links between disappearing rain and global climate change – or any other discernable climatic pattern – are less clear. What is clear is a warming trend. In 1980, Australia experienced the highest average continental temperatures on record. In 1998, that record was broken by 0.1°C. In 2005, the ’98 record was itself broken, by 0.3°C. The first five months of this year have been a whopping 1.6°C above the last record average maximum for the period, set in 1981. ‘It’s taken 25 years to break the record, but now it’s broken, we’ve smashed it,’ says Jones.
Drawing a trend line across the temperature graph indicates that the continent as a whole is warming by about 0.2°C per decade.
It’s highly likely that there is a link between this warming trend and rainfall decline. ‘Statistically, rainfall over the past ten years has been unlike any other decade over the past century,’ says Jones. ‘It would be foolish to suppose that it’s unrelated to climate change… but we dearly hope not.’
Australia’s breadbasket
The impact of rainfall declines on rivers and streams isn’t linear. A millimetre of rain doesn’t mean a dam gains by the equivalent amount. Because bone-dry soil needs to become sodden before runoff occurs, every ten per cent decline in rainfall can mean a five-fold decrease in stream flows.
In the Murray–Darling Basin (MDB), the 1.06-million-square-kilometre catchment of the 2,740-kilometre Darling and the 2,530-kilometre Murray rivers – and 21 other major rivers – this century’s drying has already had profound consequences for the region described as Australia’s breadbasket.
About half of Australia’s croplands – 11 million hectares – are in the basin. The catchment also generates a third of the nation’s beef cattle production, two thirds of its dairy production, and about 15 per cent of its wool and sheep meat.
About three quarters of Australia’s 2.5 million hectares of irrigated land is also in the MDB – except that this year, no surface water is available. On 1 July, the Australian government turned the taps off to the three quarters of the basin’s irrigators who rely on surface water. (The remainder draw on groundwater, also a dwindling resource.) Most of the basin’s 200 large water storages had been drawn down to critical levels by the middle of this year.
The Darling River, Australia’s longest, drains the flat, semi-arid inland of Queensland and New South Wales. It’s certainly no stranger to desiccation: it stopped flowing 48 times between 1885 and 1960.
In 2002, after prolonged drought, even formerly permanent water holes began to dry up. Collectors were able to walk the beds of billabongs and pick up the bottles thrown overboard from paddle steamers that plied the river during Queen Victoria’s reign. Despite some small flows since, today, the river is a sandy gutter cutting through Australia’s inland.
The Murray, whose upper-stream waters come largely from snow melt at its headwaters in the Australian Alps, is regulated by a hydro-electricity scheme built in the 1950s. Even though it retains the appearance of a river, it too is in trouble. The major dams that deliver much of its water are currently at little more than ten per cent of their capacity. Most of the dams in smaller valleys throughout the basin are in even worse shape.
Over years of floods and droughts, the mean annual discharge of the Murray–Darling system is 10,090 gigalitres. In 2004–05, towns and irrigators used about 11,000 gigalitres from the catchment under licence. The disparity between water extractions and average long-term flows hasn’t been lost on governments, which set a formal ‘cap’ on extractions in 1995. More than a decade of talking later, however, little real progress has been made on removing the anomaly.
The body charged with managing the basin’s resources, the Murray-Darling Basin Commission, warns that things are unlikely to get better. It says that estimates of the effect of climate change on the basin suggest a 5–10 per cent decrease in rainfall in the northern, summer-dominant rainfall areas, and a larger 10–20 per cent decrease in the south – with corresponding reductions in stream flows.
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Stressed systems
If the humans who depend on the rivers are feeling the effects of drought, the rivers are feeling it more. In a 2000 national audit, about a third of Australia’s rivers were classified as being in ‘extremely poor condition’, and the situation has since been exacerbated by drought.
The curlew sandpiper and the red-necked stint are in decline on the Coorong, a 50,000-hectare coastal wetland system in South Australia that was once fed by the interplay between the Murray and the tidal flows at its mouth. Pelicans no longer breed there. Brine shrimp are on the increase, however, as the water at the lower end of the system becomes saltier, and the shrimp-loving Australian banded stilt has followed.
Flows into the Coorong have been in decline for 20 years; for the past four, there have been no inflows into the wetlands at all. Leading freshwater ecologist Professor Peter Cullen believes the wetland may be doomed unless thinking about ecological management of water changes.
‘Australian aquatic ecosystems are adapted to drought, but between natural drought and man-made drought we’ve stressed systems beyond their normal capacity,’ Cullen says. ‘We have to rethink the way we manage the ecosystem. In the past, for instance, animals and plants in rivers survived drought by sheltering in deep pools. We’ve put in weirs so animals can’t get to the pools, and people are pumping out the pools for stock water.’
In some parts of the lower Murray, up to three quarters of the river red gums that line the river, or form floodplain woodlands such as the 66,000-hectare Barmah-Millewa Forest, are considered to be dying or stressed. That means much more than a loss of centuries-old eucalypts and some fine scenery, according to Professor Sam Lake of Monash University.
‘Red gums drop their leaves into streams, where they are then eaten by microbes,’ Lake says. ‘The microbes are, in turn, food for invertebrates, which are eaten by vertebrates such as fish. The red gums are a major driver of river health.’
In addition, periodic flooding in the Murray-Darling Basin’s rivers – and elsewhere in Australia – is necessary to trigger bursts of floodplain plant growth and animal breeding that pour organic nutrients back into waterways. In full swing, Lake says, floodplains are some of the world’s most productive ecosystems.
Dams and water extractions have tamed many of these flooding ecosystems, including those of the Murray. In belated recognition of the needs of flood-reliant environments, governments have, in recent years, legislated ‘environmental flows’ from some dams. In the case of the Murray, this has seen dam releases of up to 500 gigalitres at a time to replicate the sudden excesses of unregulated history. Lake acknowledges the good that this has delivered to environments such as the Barmah-Millewa Forest, but observes that it isn’t enough.
‘Environmental flows were designed to turn on river processes, but we also need flows to turn on wetlands if we’re to keep the rivers alive,’ Lake says. ‘It seems likely that we’re in for an extensive period of drying in southeastern Australia. We may have to quarantine environmental water, and take total control of how we use it if we want to keep our river environments.’
Imaginary distinctions
At the other end of nature’s spectrum, Australia’s urban dwellers have been quarantined from the effects of drought by the big infrastructure developments that began after the Second World War. But in the past few years, the imaginary distinctions between urban life and the natural world have crumbled.
For the nearly two million people living in southeast Queensland – in Brisbane, the Gold Coast and ten surrounding councils – the practical effects of too little water for too many people meant that from early April, people and businesses were only able to ‘water their gardens with buckets three times a week in the evenings’. The ‘Level 5’ water restrictions are aimed at bringing water use down to less than 140 litres per person per day. A month after the restrictions were introduced, the population was still using 152 litres per head per day – albeit an improvement on the 190 litres per head per day it consumed in wetter times.
Summer rains have already failed the region four years in succession. Dam levels are, on average, below 20 per cent, and water authorities warn that even if the target usage is met, dams will be at less than five per cent capacity within two years if no heavy rain is forthcoming.
Last year, in a race against the clock, the Queensland government announced a AU$1.7billion (£700million), 200-kilometre pipeline to take treated recycled sewage from the city and nearby Ipswich to two coal-fired power stations and, in a worst-case scenario, the city’s main water storage, Wivenhoe Dam. Construction is well underway in what is supposed to be a three-year project, but critics argue that the project is too little, a decade too late.
Perth, the world’s most remote city, realised it faced a water crisis several years ago. It wasn’t a difficult conclusion: the city’s catchments now yield half the water they did 30 years ago due to declining rainfall. The Western Australian capital draws half its water from dams, half from underground aquifers that are being inadequately recharged by diminishing rainfall.
The West Australian government responded by sinking new bores into the layered aquifers beneath the city, planning two small new dams – and commissioning a desalination plant, the country’s first. The reverse osmosis plant will eventually deliver up to 45 gigalitres a year – 17 per cent of the city’s water requirements. In a nice ‘green’ touch, the plant will be powered entirely by a wind-generation installation north of the city. Earlier this year, the government announced the commissioning of a second desalination plant, also powered by renewable energy, which will initially deliver another 45 gigalitres a year, but will have the capacity to produce 100 gigalitres. ‘We can no longer rely on traditional, seasonal climate patterns and rainfall,’ said the state’s premier, Alan Carpenter.
The Victorian government has reached the same conclusion. The parlous state of the water supply for Melbourne, the Victorian capital, was underlined earlier this year when Melbourne Water hailed a rise of a mere 0.1 per cent in its storages as good news: ‘The first time storages have risen by more than 1,600 million litres in one day since December 2005’. The inflow brought the city’s storages to 28.5 per cent full, compared to 48.3 per cent at the same time the previous year.
Confronting the grim water outlook, in June, the Victorian government announced a AU$4.9billion package to restore a reliable water supply to the state capital and its agricultural sector. Among the measures is a major desalination plant, one of the world’s largest, with the capacity to convert 150 gigalitres of seawater to potable water each year; 250 kilometres of pipeline to expand the Victorian water grid and make water more easily transferable between towns; and modernisation of irrigation infrastructure in the state’s north to prevent ‘leaks, evaporation and inefficiencies’ that will ultimately, the government hopes, deliver an extra 450 gigalitres of water a year.
The New South Wales government is moving in step. After announcing plans for a desalination plant in 2005, in June, the government doubled the specifications, announcing that the plant would be capable of producing 250 megalitres per day, ‘effectively drought-proofing the city’, according to the premier, Morris Iemma. The plant is due to be completed by 2010.
Sydney’s network of 11 dams sank to just a third of their combined 2,584 gigalitre capacity in February, but good rains throughout the catchment kicked the city out of immediate danger by mid-year, boosting capacity to 50 per cent.
In April, Adelaide’s authorities refuted media reports that it was 40 days away from running dry, saying that the city’s Murray River storages were at 56 per cent of capacity, giving the city eight months of water if there are no other inflows. The city is uniquely reliant on the stressed Murray-Darling system for its water. Good snowfalls in the Australian Alps promise a snowmelt flush down the Murray next spring, but by mid-year, the storages and rivers in the basin had received little benefit from promising autumn rains. Consequently, Adelaide, although less wealthy than mining-rich Perth, is also considering the desalination option.
Low-hanging fruit
Desalination is a relatively quick and workable answer to an urban water crisis, but like the sudden push for domestic rainwater tanks by local councils, it’s the low-hanging fruit in a whole tree full of tricky water-related questions that are casting a shadow over Australia’s future.
‘The way we do irrigated agriculture will have to be rethought; how we provide water to cities will have to be rethought,’ says NSW Natural Resources Commissioner John Williams. ‘We’ve avoided these questions for years, but out of necessity, we now have to consider major reforms.’
The possible changes are many. Lifestyle looms large among them. Australians are profligate users of water. A global study published this year ranked the water ‘footprint’ of each Australian at 341,000 litres a year – easily the world’s highest. English-style gardens and swimming pools are two inappropriate Australian enthusiasms that may have to be modified in a drier climate.
Australia’s 2.5 million hectares of irrigation will also have to be revisited. Part of the solution lies in plugging leaks and stopping the evaporation inherent in the open-channel system. If that proves inadequate, however, governments will have to bite harder and start buying back irrigation licences – forcefully. A voluntary buyback system now in place has pulled in only a fraction of the licences that must be decommissioned if water security is to be secured in over-committed catchments such as the Murray–Darling.
The nature of the crops grown under irrigation will also have to change. Cotton production used 1,821 gigalitres of water in 2004–05, dairy farming used 2,275 gigalitres, sugar 1,270 gigalitres and rice 630 gigalitres. As water becomes more scarce, and thus more valuable, low-return, water-hungry crops such as rice or even cotton may no longer be viable in Australia.
In urban areas, a national distaste for the notion of recycled water – the ‘yuk factor’ – is yet to be overcome. Sydney recycles only three per cent of its water, Melbourne ten per cent and Adelaide 20 per cent. Australian household water use amounted to 1,874 gigalitres in 2004–05; use of recycled water by households was just 1.3 gigalitres in the same year. Brisbane will have the ability to recycle drinking water when its new pipeline is completed, but politically, the yuk factor suggests that actually putting recycled water into Wivenhoe Dam will be a last resort.
Dam-building is also a political minefield. Following the successful campaign to halt the construction of the Franklin River dam in Tasmania in 1983, and with the environmental consequences of damming a major catchment better understood, governments have tended to stay away from dams out of self-preservation. Nor will a dam, which takes years to build and fill, resolve any current water crisis. Out of desperation, however, the Queensland government has flagged its intention to build two dams near Brisbane, and so far borne the subsequent political fallout.
Australia does, theoretically, have ample water for its current population. It’s just in the wrong place. Australia’s far north remains mostly undeveloped, but three of its vast catchments – the Timor, Gulf and North-Eastern – carry 60 per cent of the nation’s runoff during the monsoon season. The drought in the south, and increasing rainfall in the north, have revived ambitions to make use of this resource. Some plans involve piping the water south; others taking agriculture north. Both have serious limitations.
The West Australian government considered piping water to Perth from the huge Ord River dam in the Kimberley region, 3,300 kilometres to the north. However, the cost in infrastructure and energy to shift the water could, researchers have calculated, instead provide the city with 12 desalination plants.
A Federal taskforce is currently considering the costs and implications of opening up the north to more intensive agriculture, but the proposal faces a major obstacle. Most of the crops grown so productively in the south – cereals, oilseeds, frost-dependent horticultural crops – can’t be grown in the north’s harsh, hot climate. Cattle are able to live in the north, but the British-breed beef cattle and the dairy breeds that dominate in the south don’t perform well in these conditions.
Extreme challenges
Out of necessity, the political resolve to address Australia’s water challenges is firming. In 2004, the federal government created the National Water Initiative, a strategy to put water trading and policy on the same, market-driven basis across the country. This year, it took the extra step of taking water management away from state control and placing it under one national body. For the Murray–Darling Basin in particular, the move means that water flowing across four state boundaries is no longer subject to four different laws made in state interests.
Experienced scientists and observers recognise the extreme challenges that Australia faces, but believe that solutions can be delivered if the political will is behind them. Those solutions will have little to do with the past. ‘We simply no longer have historical benchmarks to use,’ says David Jones on climate change. ‘We have to shift from managing known risks, to managing unknown risks.’
That means, Cullen says, that Australians have to start building a ‘resilience framework’ into their cities, agriculture and ecosystems. ‘When you don’t know what’s confronting you, the ability of your systems to adapt to changing conditions is essential.’
The hidden water cost
People eat water – lots of it, embodied in our food. And in a country such as Australia, where meat is a central part of the diet, they eat even more. People also use water every time they flick the switch on an electrical outlet.
To run Australia’s current economy, taking into account factors such as exports and power generation, takes about 1.4 megalitres per person per year. Relatively little of that is drunk.
Barney Foran of the Australian National University in Canberra looked at figures for water consumption in affluent inner Sydney. Here, just ‘lifestyle’ use annually accounts for about 850,000 litres per person. About 44 per cent of that total is embodied in food, Foran says.
To put this in context, making a cup of coffee has been calculated to require 140 litres of embodied water. A litre of milk takes about 1,000 litres of water. A kilogram of rice takes 3,000 litres, and a kilogram of grain-fed beef takes 16,000 litres. Manufacturing a microchip requires 32 litres.
In Sydney’s inner suburbs, ‘having showers and watering the three pot plants we have out on the terrace and so on’ consumes another 20 per cent of ‘lifestyle’ water, Foran says. And then there’s the third of total water use that is hidden away in energy (13 per cent in Foran’s Sydney calculation) and services (20 per cent).
Foran’s response to these figures is to urge a ‘re-naturing’ of the Australian economy. ‘There has been a very concerted effort over the past 100 years of economics to take all environmental and resource implications out of what makes economic growth, and that is just not a valid way to go,’ he says. ‘Underpinning every dollar generated in this economy is an energy, a water and a land transaction, so we have to reintroduce a concept up-front that nature is well inculcated into.’
A better way of storing water
Fly over any part of closely settled Australia, and the reflection from farm dams winks back from all quarters. In warmer parts of the country, evaporation rates from such open storages approaches two metres a year.
There is a better way of storing water. ‘Aquifer storage and recovery’ (ASR) is a proven technology that involves injecting water into underground aquifers and then pumping it out when needed.
But, says hydrogeologist Dr Rick Evans of consultancy Sinclair Knight Mertz, Australia’s water is currently valued far to cheaply to make the solution viable. ‘In our gravity-fed irrigation areas, water is valued at AU$30 a megalitre – very, very cheap. A typical ASR scheme costs AU$500 a megalitre for water treatment, injection and extraction. Against current costs, the ASR method isn’t viable. But
if the real costs of surface-water infrastructure and loss were taken into account, ASR is actually cheaper.’
Australia is rapidly re-evaluating the real value of its water, and there is a small ASR scheme near Adelaide. But it’s likely that climate change will have to bite harder before ASR is picked up as a preferred water storage option. In the meantime, Evans wryly observes, ‘if we go out of our way to make dams that leak, we’re creating ASR schemes’.
Drought's depressing statistics
As this article went to press, the majority of drought-stricken eastern Australia was enjoying the best rain it had seen for years. For some farmers, however, green paddocks merely represented a chance to sell up in an up-beat market. Years of hand-feeding stock, a run of failed crops, or the inability to create mortgage repayments out of dust, have taken them to the end of the line. But perhaps not as dramatically as the media suggested in the height of the drought.
Last year, media outlets around the world reported that every four days, an Australian farmer committed suicide. It was a headline-grabbing figure, but it came from a decade-old report that actually cited a farmer suicide on average about every six days. Overall, Australian suicide figures have dropped about 20 per cent since the report was released, and some argue that rates among farmers have shown a similar decline – despite the drought.
There is no question that there has been some drought-induced suicide, although figures are unavailable. There have also been widespread reports of extreme depression among drought-stricken Australian farmers. But awareness campaigns on the dangers of depression, and greater willingness among men to be treated – although usually at the request of their wives – may have short-circuited the more extreme responses.
What remains to be seen is whether the rain brings down depression and suicide rates, or lifts them. Government forecaster the Australian Bureau of Agricultural and Resource Economics, reported earlier this year that average farm cash incomes for 2006–07 would be the lowest on record – AU$26,600, down from an estimated AU$81,290 in 2005–06. What the figure doesn’t reveal is the debt hole that many farmers will never climb out of.
August 2007
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