By ANN HINCH
Assistant Editor

ST. LOUIS, Mo. — Of all that goes into consideration of what to grow where, oddly, water availability and quality hasn’t always been high on the list – look at southern California and the water wars involved in irrigating desert land.

But water was a topic of some interest at the “Transition to a Bio Economy” conference in St. Louis Oct. 15-16. In a conference concerned with land use, financing of cellulosic ethanol manufacturing and global warming, a couple of those speakers briefly talked about how water use might be affected in the future.
In 1900, 10 million acres in the United States were irrigated; now, there are 50 million watered acres, according to Noel Gollehon, senior economist with USDA’s National Resources Conservation Service. Though there is less per-acre water usage than 108 years ago, agriculture takes about one-third of the water used in all sectors of the nation’s total economy.

Gollehon said in the short-term, there would not be a big national change in water use to grow biofuel feedstock, but local water supplies could be affected. He pointed to a “surprising density” of irrigated land in the Mississippi Delta and southern Florida, given both are near major bodies of water.

The highest use of surface water irrigation is in the West – where 80 percent of cropland in the Pacific region and 60 percent in the mountain region must be irrigated – while Plains states rely on groundwater irrigation, such as from the High Plains Aquifer (which he said is down to less than 50 feet of water remaining in the table, in some states).

Little irrigation is used in the eastern U.S. Of irrigated cropland nationwide, 17 percent is in corn.

Gollehon said there is some correspondence between the irrigation of corn and the proximity of ethanol plants, and noted he sees more such plants planned for the West. “You locate an ethanol plant for a whole lot of reasons other than feedstock,” he said, “but (water) is one of the conditions.”

If corn and other biofuel feedstock acres are expanded, he sees more water being used for them over time – depending on what kind of plants they are and where they are grown. Some “second generation biofuel” stocks require more water than corn does, and this will be an issue for individual states and communities over time, when considering the future of biofuel.

“There’s a lot of irrigable land out there,” Gollehon said of growing potential. “But, that requires both land and water.”

Too, the effect of growing on water quality will have to be considered. Silvia Secchi, a professor with Southern Illinois University’s College of Agricultural Sciences, pointed out that “growing corn is a leaky system” – referring to heavily applied nitrogen leaching into local water supplies.

Growing something else might not be better. She said switchgrass is not good for water quality because it also uses nitrogen that can leach into groundwater. It is not as low-maintenance a crop as some might think.

Some farmers might find future income in water quality conservation, such as those already participating in a nutrient credit trading system (or water quality trading, WQT) in Fairview Township, Penn., as part of the Chesapeake 2000 program. Jimmy Daukas, director of the Agriculture and Environment Initiative at the American Farmland Trust, explained how it works.

A local wastewater plant was facing millions of dollars in improvements to comply with regulations for upgrade. Instead, area farmers instituted conservation techniques that used fewer nutrients, and could then sell that “credit” of not leaking the nitrogen into local water supplies, to the wastewater plant. The WQT credits the plant needs costs less than the upgrade, and the farmers make back some money on their conservation costs, if any.

This is much like carbon credits – one business putting fewer emissions into the air, selling that ability to another business going over its allotted limit. Daukas said places in Ohio and Michigan have WQT systems, and that an Electric Power Research Institute (EPRI) of California study stated the best place to launch a multistate WQT would be in the Ohio River Basin.

Daukas said this could be integrated with conservation programs in which farmers already take part and give them a chance to earn more than one kind of income by “credit stacking” – water, carbon and the like – with an emphasis on working farmland, not retired lands. He also said ag needs more funding for conservation, and perhaps it would be better to seek that in the private sector, since maybe that would be more sustainable than public funding.
“Many of these programs have multiple benefits,” he said. “We have not been as engaged as we should or could’ve been, in involvement of agriculture (in developing credits). If we did this, we’d end up with cleaner air, cleaner water.

“Farmers can be part of the solution, improving the bio economy while improving their bottom line.”