Land of milk and honey runs dry

Far out in the Mojave Desert a potential catastrophe loomed for Southern California. A subterranean stream laced with chromium 6 - the carcinogenic agent that galvanised Julia Roberts in Erin Brockovich - flowed inexorably towards the Colorado River, a major source of drinking water for 18 million people.

By March the slow-moving groundwater, released 30 years ago at a natural gas compressor station in Nevada run by Pacific Gas & Electric, was 38m from the river. The Metropolitan Water District, which controls the Colorado River Aqueduct, raised the alarm. Several days later PG&E, which paid out US$333 million in damages in the Brockovich case, began pumping up contaminated groundwater and trucking it to a toxic waste dump.

Officials at the Metropolitan Water District seemed confident the toxic spill, which contains at least 408 million litres, would be halted before it reached the Colorado. Still, it was a near-run thing. Levels of chromium 6 were 240 times the legal limit.

The crisis underscores how dependent the world's sixth-largest economy is on imported water.

A few kilometres inland from the Pacific, Southern California quickly becomes desert. Los Angeles averages 38cm of rain a year, plummeting to 10cm during droughts. Without imported water LA's fantasy paradise of lawns, pools and golf courses would perish.

Each year Southern California consumes 3.8 million acre-feet of water (an acre-foot, or 1.23m litres, covers an acre to a depth of one foot, enough to supply eight people for a year). Ground water supplies 1.5 million acre-feet. The rest is imported by a massive network of tunnels, aqueducts, dams and pumping stations.

The history of the American West is, in large part, a saga of water wars. Water, not gold or oil, is the most precious commodity in the vast region referred to on many 19th century maps as the Great American Desert.

And nowhere have those wars been played for such high stakes as in California. Last February, environmentalists went to court to force the Department of Water and Power to start releasing water into the drought-stricken lower reaches of the Owens River, 320km north of Los Angeles to the east of the Sierra Nevada Range, by September 2005.

The parched conditions of the once-fertile Owens Valley, now subject to periodic dust storms, were created by the infamous 1910 water grab, engineered by William Mulholland, that made LA's rapid expansion possible

California's water use is profligate. "Go out to Palm Springs and you'll see all these lavish golf courses on what was desert sand," says Jack Keyser of the LA Economic Development Council. "You have to say, does it make sense economically?"

When Mulholland stole the Owens Valley water, unleashing an LA real estate boom that has rolled into the present, the city dominated the American Southwest. It still does. But now LA has to compete for imported water with Las Vegas, Phoenix and San Diego, all of which grow ever thirstier.

Last October, after a seven-year struggle with six riparian states over how much water each could tap from the Colorado, California agreed a deal with the Imperial Water District in the Colorado Desert for farmers to fallow 5 per cent of their land and sell water to San Diego.

The Imperial Valley had long enjoyed the lion's share of Colorado water. "Water is King, and Here is the Kingdom", boast signs in the heavily irrigated Imperial Valley, in which emerald fields flourish amid dazzling white sands in a harsh environment lucky to average 8cm of rain a year. Farming accounts for just US$22 billion ($34 billion) of the state's US$1.3 trillion ($2 trillion) economy, outstripped by technology, aerospace, biomedicine, tourism and entertainment. Yet it consumes 80 per cent of California's water, leaving the rest for business and urban dwellers.

With the state's population expected to hit 54 million by 2025, clearly something has to give.

"What you're seeing in California is occurring in a lot of other places," Professor Norris Hundley, author of The Great Thirst: Californians and Water: A History said last year. "Here, it's reached a flashpoint. In the long term when there's a conflict between people and agriculture in this state, people get the water."

The state's woes parallel a growing global water crisis. Water demands are beginning to outstrip supply in many regions, which is likely to worsen as the world's population grows to an expected 9 billion by mid-century.

A 2001 UN report predicted one in three people would lack fresh water by 2025. Tensions over water rights will likely be a prime cause of regional wars. To whom does water belong? Suddenly, water is a political issue.

The wild card in this volatile mix is global warming. Much of Southern California's water originates as snow in the Sierra Nevada, melting gradually to fill dams, which supply water during long, dry summers. The dams are also used to provide hydro-electricity.

But a 2002 report by the University of California at Santa Cruz predicted that climate change would raise temperatures and deplete Sierra snowpacks over the next decades.

Climate change means much precipitation will fall as rain, and snowpack could shrink by 70 per cent in 50 years. At the same time, higher temperatures mean that snow will melt faster. Faster thaws could overwhelm dams unless water is released into the Pacific.

Such waste - which would also spell big problems for hydro-electricity - could have dire consequences for America's most populous and wealthy state.

Mike Davis, whose books on California have often proved prescient, wondered in Ecology of Fear if the south would again suffer the sort of apocalyptic droughts that paleoclimatologists say twice scorched California in the Middle Ages. One lasted 220 years, the other 140 years.

Clearly, the state can't grow if there isn't enough to drink. But the impact of California's population explosion is a red-hot issue few politicians dare to tackle.

Still, faced by fierce competition for imported water, diminishing aquifers, and concerns that snowmelt will diminish, California is seeking new supplies. More than 20 desalination projects are being considered to supply fresh water from the sea.

"It's not a question of if, or whether, there will be desalination projects along the Californian coast," said Peter Douglas, executive director of the Californian Coastal Commission. "It's a question of when and where."

Advocates say 1.5 million Californians could get water from the sea by 2030. Opponents fear environmental damage to marine life and suggest treating sewage for water instead.

Poseidon, a Connecticut company, wants to build the Western Hemisphere's two largest plants in Southern California. Each would produce 189 million litres of drinking water a day.


The state can also take heart from the US Geological Survey's report in March that conservation - low-flush toilets and the like - has cut per capita water consumption in Southern California from 794 to 644 litres a day.

But, ultimately, neither desalination nor conservation will slake California's thirst. Too many people, not enough water and climate change spell a looming catastrophe.

Hard decisions about water use need to be made quickly. California has long cherished its reputation as a laboratory for change. Its people will have to hope it hasn't lost the knack.