Ocean’s Dilemma

Severe droughts are stoking renewed interest in tapping the seas. But turning their bounty into freshwater comes at great cost.

The early 1960s were a time when there seemed to be no problem so big that American technology couldn’t conquer it, including the eternal threat of drought. The solution seemed simple: build industrial plants capable of generating fresh drinking water from a limitless source–the sea. So on June 21, 1961, President John F. Kennedy inaugurated one of the first demonstration desalination plants in the U.S.–built in Freeport, Texas–with a speech that looked forward to a world where water scarcity would be a thing of the past. Kennedy argued that no water-resources program was of greater long-range importance; he dubbed the ocean the world’s greatest and cheapest natural resource. “Such a breakthrough would end bitter struggles between neighbors, states and nations,” Kennedy said.

While seawater desalination has become a vital technology in the arid countries of the Middle East–desalination produces a quarter of Israel’s water, for example–its promise has never quite been fulfilled in the U.S., hobbled by high costs and environmental concerns. But the desperation of a severe drought has a way of focusing policymakers’ attention on any possible solution, and right now California is in a drought for the ages. The state had its driest year on record in 2013, and 2014 doesn’t seem much better. At the beginning of March, more than 90% of California was in some category of drought. “We have to live with a very serious drought of uncertain duration,” Governor Jerry Brown said in his State of the State speech in January.

So California is taking a fresh look at the potential role of seawater desalination. Statewide there are 17 plants in some stage of planning along the coast, from north of the Bay Area to the border with Mexico. The biggest desalination facility in the western hemisphere is being built in Carlsbad, and when it’s completed in 2016 it will feed 50 million gal. of freshwater a day into the thirsty San Diego water system.

Seawater desalination is reliable–we’re unlikely to run out of ocean anytime soon–but industrial-scale plants aren’t cheap to build, with the Carlsbad plant checking in at nearly $1 billion. And then there are additional operating costs.

Energy costs aren’t fixed–if the price of producing electricity rises, so will the cost of desalinated seawater. And in California, electricity prices are projected to rise about 27% over 2008 levels by 2020, in inflation-adjusted dollars, thanks in part to the integration of more-expensive renewable sources. If desalinated water gets too expensive, customers may in turn reduce their water use, which can leave a desalination plant with a lot of water and no one to sell it to. It’s happened in California before. A major drought in the late 1980s led to the construction of a large desalination plant near Santa Barbara, but it was mothballed after being finished in 1992 because water from conventional sources had become much cheaper with the end of the drought.

Even in parched California, seawater desalination will likely never become a major source of freshwater. The Carlsbad plant, for example, will supply only about 7% of the region’s needs at most. Conservation and water efficiency can play a much more immediate and inexpensive role in responding to a drought than a billion-dollar desalination plant.

Seawater desalination in the U.S. may never reach the heights that President Kennedy envisioned more than 50 years ago, but it will become an increasingly important tool for water officials struggling to meet demand. For a state as parched as California, no potential water source can be ignored–especially one as big as the Pacific Ocean.

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