Biofuel Production Puts Pressure On Water

Robert M. Thorson
April 8, 2010

This is a story about robbing Peter to pay Paul — the taking of water to feed the opiate of energy independence.March 11, a freight train rumbles through the woods of Windham. Light rain falls, snow melts, the ground softens and the track bends. At 3 a.m., four railroad tanker cars carrying 120,000 gallons of flammable liquid ethanol derail above the Shetucket River. The alarm system goes off. "What the ... ?" one crew member says to another, or so I imagine. The train squeaks to a halt and the men walk back with their flashlights to investigate. Three cars are tipped and overturned. The men return to the train, notify the dispatcher and continue their trip to Providence. When first hearing this story, I embellished it in my mind as a slow-motion train wreck between our nation's energy policy moving in one direction, and its water policy moving in the other. In the aftermath of 9/11, biofuels were touted as a magic bullet of national energy independence. The calculations were computed, the studies were done, the lobbyists lobbied and Congress passed the Energy Independence and Security Act of 2007. The act mandates a fivefold increase in domestic ethanol production by 2022, with about half that goal met by 2015 with corn-based ethanol. The U.S. began subsidizing biofuel plant construction throughout the cornbelt. Also in the time since 9/11: Snowpacks diminished. Droughts threatened. Fires burned. The water levels in the Great Lakes and countless smaller ones dropped, a trend recently (and temporarily?) reversed by the unusual weather of the last two years. Meanwhile, the climate modelers firmed up their predictions that the water supply in the American heartland is on a downward trend.And now, the slow-motion train wreck. "In short, an increased reliance on biofuel trades an oil problem for a water problem." That's a quote from a recent report ominously titled "Another Biofuels Drawback: The Demand for Irrigation." It summarizes two recent studies by Argonne National Laboratory containing some stunning numbers. It takes between 10 and 324 gallons of water to create a single gallon of ethanol (with an average of 98), depending on the geography and proportion of irrigation. This transfer will increase U.S. water demand by about 1.4 trillion gallons per year, practically all from the corn-belt states. Other energy sectors also require staggering amounts of water.Worst is irrigated soybean biodiesel, which takes between 3.6 million and 7.2 million gallons of water to produce a single megawatt hour of electricity. In comparison, oil shale extraction requires only 44 to 171 gallons per megawatt, and petroleum extraction only 2.6 to10.4 gallons. U.S. water consumption for energy development is predicted to rise by two thirds to about 10 billion gallons per day by 2030. Approximately half that increase will be for rising population and the other half for legally mandated biofuel conversions. Over that period, the proportion of land being irrigated for biofuels will rise dramatically from 3 percent to 20 percent. Any leftover water will drain to the Gulf of Mexico, carrying with it the excess nutrients and pesticides that were needed to grow enough corn to produce enough fuel to meet the mandates to make us feel good about energy independence. As a result, the Mississippi River stagnates, the bayous breathe more laboriously and the low-oxygen dead zone beneath the Gulf enlarges. Meanwhile, petroleum-diesel train engines haul ethanol tankers eastward under cover of night. An accident occurs, tankers tip, an innocent freshwater resource is threatened, and dozens of large vehicles — fire, ambulance, police, troopers, hazmat teams, regulators, press, television — all powered by fossil fuels, come to investigate. I wonder if they saw what was taking place behind the scenes on that dark night. •Robert M. Thorson is a professor of geology at the University of Connecticut's College of Liberal Arts and Sciences and a member of The Courant's Place Board of Contributors. His column appears every other Thursday. He can be reached at profthorson@yahoo.com.
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