"In fact, ocean desalination does not work"

Food & Water Watch responds to HTWW; Marin County shouldn't be considering an unproven, unreliable technology

Published April 19, 2007 8:53PM (EDT)

Zach Corrigan, a staff attorney and legislative representative at Food & Water Watch, takes issue with my criticism of their assertion that one reason to oppose desalination plans is that the technology "doesn't work."

Mr. Leonard's article says we were misleading in one of our factsheets when we say that desalination doesn't work. Mr. Leonard, you might not want to throw out our "it doesn't work" argument quite yet.

While it is true that the United States accounts for 17 percent of the global capacity of desalination, this is a figure that includes all forms of desalination. Our factsheet was solely about ocean water desalination. Mr. Leonard misses that on the very next page of the Pacific Institute's report, it shows that the water treated in U.S. desalination plants is different in the rest of the world. The great majority of water we desalinate in the United States is river or brackish water, which uses less energy and is more cost-effective to desalinate. Only 7 percent of the U.S. installed capacity for desalination is seawater.

Even this 7 percent figure is misleading. It measures installed capacity, or how much water could be produced through already-built seawater desalination plants -- not the amount of water that is actually produced. So, counted in the figure is one of the largest plants proposed in the United States, the Tampa Bay plant, which, despite the more than $110 million price tag, has never produced drinking water commercially or even reliably. Also included is one of the largest plants built in California, the Santa Barbara, which also has never operated commercially.

All this is to say that ocean water desalination is not a technology that has proven to be a viable or reliable alternative in the United States. The $110 to $173 million proposed plant in Marin should be viewed with extreme skepticism. The last thing that San Franciscans need is a boondoggle like the one in Tampa Bay or Santa Barbara.

Moreover, the real point of our blog is that, even if the plant works, it will certainly undercut the Marin Water District's first-in-the-nation commitment to reduce global warming pollution by more than tripling the water district's energy use. The water board president has proposed that the desalination plant be powered by solar power or some other combination of renewable energy. While these technologies are worth exploring, their viability for producing the amount of energy needed to produce drinking water form ocean salt water is even less tried than conventional desalination.

Measured against the water district's commitments, it becomes even more hazy whether this proposal will truly work.

-- Zach Corrigan, Food & Water Watch

By Andrew Leonard

Andrew Leonard is a staff writer at Salon. On Twitter, @koxinga21.

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Environment Global Warming Globalization How The World Works