Australians, proudly “sunburnt” according to the hackneyed national myth, have withstood long dry spells before. But the current seven-year drought has come to be known as “the big dry.” It is the longest, hottest and most devastating in the country’s history. To Tim Flannery (Australian evolutionary biologist), Australia, the world’s 15th-biggest economy, is a climate canary, learning first the hard lessons on the limits of water in an era of shifting weather patterns. He reckons the western U.S. may be hit next.
The crisis in Australia is an extreme version of shortages hitting the U.S. Southwest, Israel and North Africa, focusing attention on what may be the most immediate environmental crisis facing the world: shortages of water. Far more than oil, our societies run on water. And unlike oil, there is no substitute for it. Yet an increasing body of evidence suggests there simply isn’t enough to support future population and economic growth, not to mention waste born of years of abundance in places like Canada, one of the world’s biggest water consumers.
From Tofino to Tucson, hydrologists, limnologists and government ofﬁcials are reporting similar climatic trends: a longer dry season, less snow, more rain and earlier spring melts. “Half the annual flow of the Fraser now occurs nine days early,” says Steve Litke of the Fraser Basin Council, a Vancouver NGO that studies the health of the massive watershed—home to two-thirds of B.C.’s population. These shifting climate patterns are changing “where, when and how” water falls and flows, eroding our ability to manage water for large populations, says Meena Palaniappan, with the San Francisco-based Pacific Institute.
Take California: snowpack from the Sierra Nevada mountain range provides the bulk of its water. But even the most optimistic climate models are showing a 30 to 70 per cent reduction of the Sierra Nevada snowpack by the second half of the century. This year, snowfall in the mountain range was down to about two-thirds of normal. By 2050, California’s population will have grown to 60 million, up from 36 million today. The “exploding” human population in the U.S. Southwest and its shrinking clean water supply are clearly on two “colliding paths,” acknowledges Pat Mulroy, the outspoken head of the Southern Nevada Water Authority. She oversees Las Vegas, the most vulnerable metro area on the continent, still “very much in the throes of an ugly drought” now entering its ninth year.
By contrast, Canada, with 20 per cent of the world’s freshwater resources, and less than one per cent of its population, looks like the Saudi Arabia of water. China, for example, has less than half Canada’s supply and 40 times as many people. Still, scientists warn that Canada is facing a distribution problem: 80 per cent of the country’s water resources are locked in the north, while 80 per cent of the population is packed along the U.S. border. Freshwater is scarce in Manitoba, Saskatchewan and Alberta, says David Schindler, one of the country’s top water scientists. There, he adds, lakes were retreating even in the 20th century: the wettest century of the past millennium, according to tree-ring fieldwork done by the universities of Arizona and Regina. Schindler predicts a likely mid-century return to ’30s-era, “dust-bowl” conditions—yes, even in Manitoba, land of 100,000 lakes—noting a 30 to 85 per cent reduction in summer river flows in the previous 30 years.
As aquifers under Beijing, Delhi, San Antonio and dozens more cities with mushrooming populations dry up, some experts suggest the era of cheap, easy access to water is coming to an end. Palaniappan calls it “peak water”: the point when demand outstrips renewable supply, and resources trend ominously downward. Humans, she says, are extracting and polluting it faster than it can be replenished. “In the developing world, more than 90 per cent of all sewage, and 70 per cent of industrial waste, is dumped untreated into surface water,” says Robert Sandford, Canadian chair of the UN Water for Life initiative, noting that 75 per cent of the river water flowing through China’s cities is unfit for drinking or fishing. This summer, Lake Mead, the largest reservoir in the U.S., which supplies nearly all the water for Las Vegas, fell to 43 per cent capacity. The Scripps Institute of Oceanography has given it 50-50 odds of surviving to 2021. Levels on the Sea of Galilee, the largest freshwater source in Israel—locked into year five of a devastating drought—have fallen to within inches of the “danger line.” Last year, Atlanta came within 90 days of running out of water.
The economic impact of water scarcity is grim: in the past two years, new power plants in four U.S. states, as well as several dozen commercial and residential development projects in California, have been cancelled because developers weren’t able to secure long-term water supplies. This summer, as California approaches its fourth year of drought, up to 30,000 workers will be laid off in its 650-km-long Central Valley, the country’s agricultural engine. Economic losses could top a half-billion dollars. In Australia, they’ve surpassed $20 billion.