The U.S. craze for ethanol could severely strain an already ailing aquifer in key farm states, increasing demand for scarce water supplies by more than 2 billion gallons a year, according to a report issued Thursday by the nonprofit group Environmental Defense. The environmental group's report focused on the Ogallala aquifer, an 800-mile-long underground pool that stretches from Texas to South Dakota. The Ogallala feeds one-fifth of all the irrigated land in the United States, and is critical to farmers growing corn, cotton, wheat, soybeans and other crops.

The report states that between three and six gallons of water are needed to produce one gallon of ethanol, potentially increasing demand on the already declining Ogallala by as much as 2.6 billion gallons a year just to process the corn and produce the fuel. Another 120 billion gallons a year could be needed for irrigation to grow more corn in the region, according to the report.

"The Ogallala Aquifer is a microcosm of the challenges we'll face in America as we develop renewable fuels," said Martha Roberts, co-author of the report and a fellow at Environmental Defense. "Nine new ethanol plants are already planned for some of the most water-depleted areas of the Ogallala Aquifer, even though those areas are vulnerable to erosion and the entire region's water resources are stretched thin."

Ethanol proponents downplayed the concerns. "Most of the water concerns that are expressed about ethanol plants are way overblown," said American Coalition of Ethanol spokesman Ron Lamberty. "The average person on earth uses 100 gallons of water a day." Lamberty said some of the water used to make ethanol is returned to the environment in the form of steam. He also said ethanol plants will not be locating where water availability is a question.

Demand for ethanol has spiked as the U.S. works to wean itself from foreign oil and corn production skyrocketed this year. According to the ethanol coalition, there are 132 ethanol plants currently in operation with a capacity for 6.8 billion gallons a year and 79 under construction with capacity for 5.7 billion gallons. Most of the ethanol development is in the U.S. Midwest.

The Environmental Defense report recommends maintaining or expanding the Conservation Reserve Program, which provides cost-share and rental payments to farmers and ranchers who retire cropland to grass cover, and the Grasslands Reserve Program, which pays farmers and ranchers permanent easement or rental payments to protect, restore or enhance grasslands or grazing operations.

(By Carey Gillam, Reuters, 20/09/2007)