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Murky solutions in the water crisis

ANYONE who has taken a sip from a drinking fountain at Disneyland recently may have unknowingly sampled a taste of the future - a small quantity of water that once flowed through a sewer.

Orange County Water District officials say that's a good thing, the result of a successful, year-old project to purify wastewater and pump it into the ground to help restore depleted aquifers that provide most of the local water supply.

The US$481 million recycling plant, the world's largest of its kind, uses microfiltration, reverse osmosis, ultraviolet light and hydrogen peroxide disinfection to treat 265 million liters of sewer water a day, enough to meet the drinking needs of 500,000 people. Just don't call it "toilet-to-tap."

County officials prefer the term "Groundwater Replenishment System," a name chosen after similar projects in Los Angeles and San Diego fell prey to public misconceptions, also known as the "yuck factor," and local election-year politics.

Their experience underscores one of the great lessons facing municipal officials across the US West as they seek to bring purification and recycling technologies to bear against drought cycles expected to worsen with climate change. Scientists, policy makers and investors agree ample know-how exists to solve the water crisis; the difficulties lie in energy constraints, economics and politics.

"We can solve most, if not all, of the world's biggest water problems with technology that exists today," said Stephan Dolezalek, who leads the clean-energy practice of Silicon Valley venture capital firm VantagePoint Venture Partners. "What we may not have is the willpower."

Pumping stations

Experts say price distortions in the West, where government has long subsidized farm irrigation and the cost of pipelines and pumping stations to send fresh water from distant sources to cities, have discouraged the development of new supplies.

"The water that we use in the West is generally undervalued," said Tim Barnett, a marine research physicist for the Scripps Institution of Oceanography at the University of California, San Diego.

The math has changed as the region's water grows scarcer, its population swells and environmental pressures mount.

"This is a new day, and we have conditions which compel us to look to new water resources," said David Nahai, general manager of the Los Angeles Department of Water and Power, the nation's largest municipal utility.

He and other water managers see tremendous potential in stepped-up conservation, from encouraging more waste-conscious personal behavior to installing low-flow showers, toilets, appliances and lawn sprinklers.

Such measures could add more than 43.5 billion cubic feet of water - enough for 8 million people - to Southern California's regional supply alone, or about 25 percent of current annual use, according to an economic development report.

Further gains are possible by replenishing groundwater basins with rainfall runoff that normally flows to sea.

Water managers say they now realize that an aggressive public education campaign is key to building support.

They want the public to understand that much of what comes from the tap today is recycled sewer water.

The Colorado River, for example, contains large amounts of heavily treated waste discharged from cities upstream, including Las Vegas.

But as an LA County Economic Development Corporation study puts it, "what happens in Vegas doesn't stay in Vegas."


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