If U.S. ethanol production continues to rise, the effect on water quality could be considerable and water supply problems could develop, says a new report today from the National Academy of Sciences' National Research Council.

Increased pressure on local aquifers used to grow and refine corn into ethanol, high levels of nitrogen in groundwater from pesticides and fertilizers, and runoff pollution in streams and rivers are a few of the potential impacts, said the committee that wrote the report.

Chaired by Dr. Jerald Schnoor, a professor of engineering at the University of Iowa, the six member committee examined policy options and identified opportunities for new agricultural techniques and technologies to help minimize effects of biofuel production on water resources.

Recent increases in oil prices together with subsidy policies have led to a dramatic expansion in corn ethanol production and high interest in further expansion over the next decade.

Because of strong national interest in greater energy independence, in this year's State of the Union address, President George W. Bush called for the production of 35 billion gallons of ethanol by 2017, which would equal about 15 percent of the U.S. liquid transportation fuels.

The committee found that agricultural shifts to growing corn and expanding biofuel crops into regions with little agriculture, especially dry areas, could change current irrigation practices and greatly increase pressure on water resources in many parts of the United States.