01.09.2008

Our Water Future

With memories of recent drought still vivid in most parts of Australia, how we use water is uppermost in most of our minds. A new book suggests that, once again, the choices we make as individuals are vital for our future. Story by Nicola Silva

With memories of recent drought still vivid in most parts of Australia, how we use water is uppermost in most of our minds. A new book suggests that, once again, the choices we make as individuals are vital for our future. Story by Nicola Silva

Those who are fond of quoting poet Dorothea MacKellar's words about this sunburnt land, often do so out of patriotism rather than for the realism embedded in her poetic imagery. Australia truly is a land "Of drought and flooding rains", but for a very long time we have been living as if this were not the case.

Now, one of the most severe droughts ever experienced, and irrefutable proof of climate change require us to look at our land with new eyes. Information is vital for widespread change to occur, and a new book, Thirsty Country, by journalist Asa Wahlquist, paints a holistic picture of Australia's water resources and how science can help us make the most of them.

Wahlquist describes water as "an every day miracle". We turn on a tap and out comes water safe enough to give a baby. Although we live on the driest inhabited continent, water is literally free as the charges levied are for supply and purification. Have we, as a society, paid too little attention to this precious resource, taking it for granted? The evidence is an overwhelming yes.

How thirsty is Australia? Consider these facts. Only Antarctica is drier than our continent. Australia has an annual average rainfall of 457 mm, but the quantity that goes into the rivers, streams and lakes, known as "run off", is only about 10 per cent. In comparison, Europe has a run off rate of 39 per cent and Africa, 38 per cent. There is huge loss of water through evaporation, which exceeds rainfall in most places, and can even be 10 times higher than rainfall. Most of our rainfall comes from the ocean, and thus has a high salt content. And one last fact - because there has been no recent glaciation of the Australian landmass, it lacks the deep and fertile soils evident for instance, in North America.

"Ours is an ancient landscape, flat and eroded, dry and thin skinned, low in fertility, with an ancient plant and animal population - and that poses particular problems," Wahlquist writes.

Our landscape is both fragile and sustained by complex ecosystems, where any change extracts a heavy toll; the proof is in our high rate of species extinction.

Into this alien landscape, for so it would have seemed to them, came the European settlers. They searched in vain for the gushing brooks and strong flowing reliable rivers akin to the Thames that had been a part of their native environment. Even the Darling River, with its brackish water, was a disappointment to Charles Sturt and his men.

Oblivious to variable rainfall caused by El Nino patterns (this would not be understood for 200 years), the settlers set out to green the desert. They planted European crops, diverting water for towns and agriculture. They dammed rivers to obtain more reliable flows. The echoes of this sentiment still echo today in periodic calls to "drought proof" the land. This is perhaps one of the more enduring myths regarding water, because it fails to acknowledge what Dorothea MacKellar expressed so evocatively - this is a land of extremes.

"Australia is a country where, despite the expectations of its inhabitants, the water supplies are, to a greater or lesser degree, a matter of boom and bust. And those booms and busts are determined by our climate," Wahlquist states unequivocally.

The search for a regular and reliable water supply inevitably led administrations to build dams, which we have done with typical Australian ingenuity and great success. Projects such as the Snowy Mountains Hydro Electric Scheme are part of our nation building narrative. There was a veritable boom of dam building after the 1950s as populations grew rapidly: most of the more than 500 dams that exist today were built during that period.

Dam water is cheap and for decades governments have relied on it to supply our fast growing cities, merely restricting water use during periods of drought. The current water crisis is thus a wake up call for individuals and communities that we can no longer rely on governments and big water utilities to supply our water future. Since 1990, they have failed abysmally to plan for, and invest in, sustainable sources of water, with the exception of Perth.

Wahlquist describes Perth as the first climate change city in Australia. Since 1975, rainfall in Perth has fallen rapidly and, by 2005, a 20 per cent decrease was evident. The impact on Perth's dams was more dramatic - inflows reduced by 66 per cent between 1997 and 2005. Significant action was required, and Perth authorities invested more than one billion dollars in sourcing new water, such as accessing ground water supplies, which has doubled the city's water supply. The city was the first in Australia to build a desalination plant, which supplies 17 per cent of Perth's water.

Wahlquist argues that around Australia we require "a portfolio of water sources" to secure our future. We must move away from the centralised solutions favoured by government authorities. There is much that individuals and communities can do, and are already doing.

People often comment that the dams are in the "wrong" place. This is because coastal cities like Sydney and Brisbane receive more rainfall than the dams, and yet it ends up as stormwater. Yet 20 years ago, it was illegal for Sydney households to install rainwater tanks - no doubt authorities feared a loss of revenue. Today, approximately 17 per cent of Australian households have water tanks - in drought conscious Adelaide this figure is 40 per cent. One report has found that if just 5 per cent of Sydney and southeast Queensland households installed rainwater tanks each year, it could put off the development of new water sources for at least one decade.

Some other water saving methods around the home are: Shorter showers using a waterwise showerheadOpting for water saving washing machines and dishwashersUsing pool covers to reduce evaporation - approximately 4 billion litres is lost in evaporation from Perth pools each year.

Wahlquist also draws attention to "virtual" water, or our shopping, which represents about half the water used at home. I had not realised that a basket of everyday items such as a loaf of bread, butter, a litre of milk, 500g beef and a few kgs of fruit and vegetables requires more than 30,000 litres of water to grow. It's great motivation for growing your own fruit and veggies as home gardeners use less water than farmers.

It is also critical that we inform ourselves of the facts of water recycling, an area that is awash with myths and misinformation. Wahlquist asserts, "(T)he phrase 'toilet to tap', is one of the great lies of Australian political lobbying. It is big on the yuck factor, but short on the truth. The fact is there is no such thing as new water. All water is re-used, whether it falls as rain or is pumped out of a dam, or comes out of a recycling plant."

We have the technology to purify water to a very high standard. Highly treated sewage is re-introduced to some of the best known rivers in the world including the Thames, Rhine, and Mississippi and Hudson Rivers.

In Australia, recycled water is mainly used outdoors, in agriculture and to a limited extent in industry. Sydney's Rouse Hill delivers recycled water to 16,500 households via a purple garden tap, with the sign "recycled water - do not drink". There are plans to extend this scheme further in Sydney and also on the Gold Coast.

Increasingly, local councils are harvesting stormwater and using recycled water on parks, golf courses and sportsfields. Adelaide uses recycled water from Christies Beach to irrigate wine grapes. Adelaide has had to be resourceful as its dams hold less than one year's supply and solutions have come from a range of options, including aquifer storage.

One of the paradoxes of Australia, Wahlquist highlights, is that while we have some of the most technologically advanced agriculture in the world, there is also a great deal of wastage due to poor infrastructure and out-of-date allocation systems. Notions of greening the desert, led to cheap, subsidised irrigation without proper scientific analysis and this has cost the health of our rivers. The first wake up call came in December 1991 when the Darling River became infected with a toxic blue-green algal bloom spreading for 1,000 km. A few years later, the Salinity Audit of the Murray-Darling Basin found that by 2020 people in Adelaide would not be able to drink the water two days out of five.

Federal and state governments are finally awake to the plight of our ailing rivers and are spending billions of dollars on returning water to the environment. There is no quick fix, however, as it will take decades of sustained investment and conservation to bring the rivers back to their former vitality, if ever. This is because climate change is almost impossible to predict with a high degree of accuracy.

In the meantime, big questions remain: ageing irrigation systems like that in Melbourne, which currently loses double that city's water supply, must be replaced. The whole question of water allocation needs to be re-visited on the basis of science and sustainability. Can we afford to have widespread agriculture, especially in areas that are no longer viable, even with irrigation?

I must admit to some uncomfortable moments when reading Thirsty Country chiefly because I knew so little about our water resources although, like most, I have reduced water use in a number of ways. As a nation, Australians have the ingenuity and courage, the scientific know how and technology to make the tough decisions that will ensure a sustainable future, but we cannot leave it to bureaucrats and politicians.

As Wahlquist points out, "Our water future will depend on the effort of individuals and households, on the community, and on our regions as well as the state. Curbing our water use, installing household rainwater tanks, collecting storm water, treating waste water, using ground water, buying in water, using water from dams and desalination must all play a role if we are to no longer be the thirsty country."

Thirsty Country
Asa Wahlquist
Allen & Unwin
RRP Aus $27.95

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