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Ethanol and Water

In the case of corn, it takes 2,500 gallons of water to grow enough corn to produce 1 gallon of ethanol. That's right, 2,500 gallons.
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If I could offer our soon-to-be Secretary of Agriculture Tom Vilsack one piece of advice, it would be this: "We're already running low on water. Don't make matters worse."

I would offer my advice with hope, but out of fear. My fear is that in Des Monies and in his short-lived presidential campaign, Mr. Vilsack was an ardent supporter of ethanol, so has been President-elect Obama. Once he becomes agriculture's advocate in the new administration, it will mean more and more ethanol plants for America.

Mr. Vilsack is in for an unpleasant surprise.

That's because while many of ethanol's problems (energy inputs, land use, food prices and more) have been thoroughly discussed, we have oddly (or maybe purposely) overlooked its true Achilles heel: water. And if we stick to our current plans to massively boost ethanol, an ethanol-fueled water crisis will come fast and furious.

Producing ethanol requires enormous amounts of water. Water America does not now have. That's true for corn ethanol and its supposedly more efficient and environmental cousin, cellulosic ethanol made from husks, wood chips, and other waste. The most efficient ethanol plants need 4 gallons of water to produce one gallon of ethanol fuel. That doesn't account for the feedstock, and in the case of corn, it takes 2,500 gallons of water to grow enough corn to produce 1 gallon of ethanol. That's right, 2,500 gallons.

Look at what happened in Minnesota: In June 2006, Governor Tim Pawlenty heralded the grand opening of a 40 million gallon-per-year ethanol refinery by Granite Falls Energy. Lost in the excitement was the fact that the plant consumes almost 400 gallons of water per minute. It didn't take long before wells 3 miles away started to run dry leaving families without water.

To "solve" the problem, engineers started diverting water from the Minnesota River, a "solution" which might work until the next drought. To say the least, it portends trouble when one modest-sized plant in, of all places, the Land of Ten Thousand Lakes, is straining water supplies.

Nationwide, there were only 54 ethanol plants in 2000. By 2008 that number had grown to 139, with an additional 62 refineries under construction. Mr. Vilsack and others will oversee an ethanol boom created by large production mandates in the Energy Policy Act of 2005. The existing and proposed plants will have the capacity to produce 12 billion gallons of ethanol. Refining that much ethanol will consume 48 billion gallons of water. And that's just for the production process. First farmers must have water to grow the corn or whatever else will feed the plants.

The state of California has a goal of producing a billion gallons of ethanol a year. To grow enough corn to refine that much ethanol would take as much as 2.5 trillion gallons -- more than all the water from the Sacramento-San Joaquin River Delta that now goes to Southern California cities and to Central Valley farmers. The Delta supplies water to two-thirds of the state's residents and irrigates more than 7 million acres of some of the nation's most productive farmland.

In the words of Donald Rumsfeld, this looming water crisis is a "known unknown" that Washington seems determined to ignore even as it creates it.

Across America cities and towns are already struggling to provide residents with clean water. Georgia's Governor Sonny Perdue organized a prayer group on the steps of the state capital in the name of rain. Planners are floating schemes to channel water from the Mississippi across thousands of miles of continent to Las Vegas. Along the South Carolina coast, fresh groundwater is flowing backwards it is being drained so rapidly.

Just wait until we start turning what water we have left into fuel for cars and trucks by the trillions of gallons. It won't work, Mr. Secretary.

Robert Glennon is the Morris K. Udall Professor of Law and Public Policy at the University of Arizona. His new book, Unquenchable: America's Water Crisis and What To Do About It, will be published by Island Press in March 2009.

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