Scientists stress wise water use in corn ethanol boom

Boosting production of corn ethanol will increasingly stress the nation's water resources, concludes a new report released Wednesday by a national science organization.

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buy this photo An ear of corn is seen in this April 13 photo. (AP file)

Boosting production of corn ethanol will increasingly stress the nation’s water resources, concludes a new report released Wednesday by a national science organization.

More specifically, growing lots more corn using current farm practices will come at a huge water cost to Nebraska and other states where the fuel is made.

The costs entail depleted underground water supplies and a flow of agricultural chemicals and eroded soil into rivers, lakes and oceans, according to the report, “Water Implications of Biofuels Production in the United States.”

The report also describes options policymakers could pursue to help protect water while still ramping up biofuel production.

The 58-page report was published by the National Research Council, an arm of the National Academy of Sciences. Congress established the academy to provide independent policy advice on science, technology and health issues.

The report grew from a meeting on biofuels and water attended by 130 experts from science, academia and the ag and ethanol industries in Washington, D.C., this summer. A committee of six university professors drafted the report and then obtained independent reviews from government, policy and industry representatives with expertise in the subject.

The committee sought to provide an objective analysis of the implications of biofuels on water to help the nation chart its energy future, said committee Chairman Jerald Schnoor, professor of environmental engineering at the University of Iowa.

Biofuels are “here for the long run,” Schnoor said. “The issue is how can we produce biofuels in an environmentally friendly and beneficial way?”

Simply planting more corn, especially in highly erodible or sandy soils, doesn’t qualify as environmentally friendly.

Today, ethanol refineries produce about 6 billion gallons of the corn-based fuel a year. President George W. Bush has set a goal of 35 billion gallons of biofuels by 2017.

The problem with corn is that it requires a lot of chemical additives, particularly nitrogen and phosphorus fertilizers. Some of those chemicals contaminate underground water supplies and some wash into rivers and streams. Ag chemicals are largely responsible for massive aquatic dead zones in the Gulf of Mexico and the Chesapeake Bay, the report states.

Corn also requires lots of water. In states like Iowa and Illinois, most of the water comes from rain. But in states further west, such as Nebraska, most acres are irrigated. As a result, water is being pumped from the Ogallala Aquifer, which lies under much of Nebraska, at rates faster than the aquifer can be recharged.

“It is equivalent to ‘mining’ the water resource, and the loss of the resource is essentially irreversible,” the report said.

Ethanol can also be made from prairie grass, trees or other sources of plant starch, but such cellulosic ethanol is still in the research and development stage.

Cellulosic ethanol certainly shows promise as a more environmentally friendly fuel, but that can’t be definitively proven, Schnoor said. The cellulosic stage of ethanol development appears to be at least five years away.

The National Research Council report recognized that farmers can employ improved technology and practices to use water and chemicals more efficiently. Such technology and practices should be encouraged by policies, either as incentives or penalties to crop producers, said Otto Doering III, an agricultural economics professor at Purdue University and a member of the committee that produced the report.

“We may have to have a little more of the two-by-four as well as the carrot as we push the fringe on land quality,” Doering said.

Other policies can help protect water as biofuel production increases. For example, the report mentioned switching from the flat 51-cent subsidy for ethanol to one that would fluctuate along with the profit margin  of the fuel. During times when the ethanol market was strong, the subsidy could be invested on cellulosic research, Doering explained.

For both ethanol and environmental advocates in Nebraska, the report’s findings came as no surprise.

Duane Hovorka, a staff member of the National Wildlife Federation in Nebraska, said he fears the expanding ethanol market could lead landowners to plow under grasslands that provide habitat. The report underscores the importance of long-term thinking on such issues.

“I do think we're at a critical juncture in our state,” he said. “The decisions we're making now, that's what our kids and grandkids are going to have to live with.”

Todd Sneller, administrator of the Nebraska Ethanol Board, said both farmers and ethanol plant owners understand the importance of using water resources wisely. At a board symposium earlier this year, four agenda items involved water.

He called the report fair, with one exception. He questioned whether it gave the impression that corn growers want or expect to meet the 35-billion-gallon goal by 2017. Most believe 15 billion gallons would be the maximum amount supplied by corn, Sneller said.

“If we're good stewards, good mangers and do this in a sustainable way, most in the industry agree 14 to 20 billion gallons,” he said. “Anything beyond that needs to rely on cellulose or something besides grain.”

Reach Joe Duggan at 473-7239 or jduggan@journalstar.com

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