Water: It's one of the fundamental basics required for human survival; the element that sets the planet apart from many lifeless others.

With recent rising oil prices, the U.S. has focused much of its attention on the depletion of oil reserves and on developing alternative energy sources such as ethanol.

But the depletion and pollution of underground water resources could be a far more serious issue, according to current data.

"Agriculture is the most water-intensive sector of the economy," stated Lester Brown, founder and president of Earth Policy Institute, a Washington, D.C.-based independent environmental research organization.

The average person drinks nearly four quarts of water a day in one form or another, but the food we consume each day requires 2,000 quarts of water to produce -- roughly 500 times as much, Brown said.

"Seventy percent of all water pumped from underground or diverted from rivers is used for irrigation," Brown noted, adding that 20 percent is used by industry and 10 percent goes to residences.

In a recent panel discussion on emerging energy issues, Amy Kaleita, Ph.D. and assistant professor of agricultural and biosystems engineering at Iowa State University and public policy fellow in environmental studies with the Pacific Research Institute, stated that feedstock production for alternative energy sources in addition to food production poses serious threats to water quality and quantity.

Soil erosion is one contributing factor.

"Not only does soil erosion damage soil quantity and quality at the source, but it is also a concern for water bodies downstream that receive those eroded sediments," Kaleita said. "Problems associated with sedimentation include silting in of reservoirs and waterways, and increased transport of chemicals such as pesticides adhered to the sediment particles, which increases the concentration of those chemicals in surface water supplies."

Kaleita added that increased agricultural intensity, including increased land in production and an increase in land that is continuously planted in the same crop year after year, will require significant increases in fertilizer application.

"Nitrogen, one major element of crop fertilizer that is soluble and very mobile in one of its most common forms -- nitrate -- is easily transported in water that drains from fertilized fields," Kaleita said. "Nitrate export from the corn belt is, even today, tightly associated with problems of hypoxia, or low dissolved oxygen content in water."

She added that hot spots for nitrate export are, generally, in the states that are currently producing the most corn.

In a recent study conducted by J.L. Hatfield, laboratory director for the U.S. Department of Agriculture's National Soil Tilth laboratory in Ames, Iowa, it was observed that pesticide occurrence in streams and lakes adjacent to agricultural fields have prompted much discussion about whether to ban or greatly restrict agricultural activities that would potentially impair water quality.

He noted that equally important to the issue is the recognition by producers that not all fields behave the same.

"There is a need to develop more site-specific information that can be used for planning and management," Hatfield said.

As farm bill negotiations continue, conservation security programs (CSP) are up against issues of energy production, rural development and a host of public service programs all vying for funds.

But some projects already in place are leading the way to protecting water resources.

"We have several programs that work to accelerate conservation practices," said Jeff Stewart, Resource Conservation and Development (RC&D) coordinator in Lake Andes.

The Lewis & Clark Watershed Implementation Project is one such program. It is designed to encourage landowners to incorporate conservation programs into their land management and production practices.

"The watershed project has funding available to assist with feedlot waste management, planned grazing systems, grassed waterways, tree planting, filter strips, pipelines, tanks, ponds, dug-outs, and grassland buffers," Stewart said.

Watershed areas often encompass hundreds or thousands of acres, requiring cooperation from many individual landowners.

"We're getting a positive response from landowners," Stewart said, adding that educating the landowners is the first step.

"Everybody in the U.S. has a lease on your land, in a sense," Stewart said. "People in New York City are affected by some landowner in Douglas County that pollutes the water. They may own the acres, but they can't just do whatever they want when it comes to mistreating the land."

Stewart added that addressing the problems with water pollution is "an education process that needs to continue."

Programs like the Lewis & Clark Watershed Implementation Project can help ease pressures on water resources, but according to Brown, the bigger picture of the world's water problem is really about food security.

"There are substitutes for oil, but there are no substitutes for water," he said.

Brown added that as the world's population grows, so does its economy, placing demands on the earth that exceed the planet's natural capacity to provide the basic needs of daily living.

Brown cited rising temperatures and falling water tables as the two main threats to world food security.

"Historically, it was the supply of land that constrained the growth in food production, but today the shortage of water is the most formidable barrier," he stated.

But the water problem isn't a stand-alone issue.

"If countries do not act quickly to raise water productivity, falling water tables could soon translate into rising food prices," Brown said. "Given the effect of rising temperatures on crop yields, the urgency of cutting carbon emissions sharply cannot easily be overstated."

The current push for ethanol as the answer to fossil-fuel dependence may help to slightly curb carbon emissions from the consumer end, but the environmental ramifications for producing ethanol feed back into the problem once again.

"At the production facilities themselves, 3-4 gallons of water are consumed for every gallon of ethanol produced," Kaleita said. "That doesn't include the water that is recycled within the facility. To satisfy this demand, surface water and groundwater withdrawals will have to increase."

Kaleita added that this, coupled with increased irrigation demand for crop production -- especially in the Great Plains -- raises significant concerns over water quantity.

"Water availability is expected to challenge the ethanol industry in many regions, particularly west of the Missouri River," Kaleita said. "This isn't just hypothetical: Already, a number of proposed plants have been tabled due to lack of access to the necessary amounts of water."

While solutions are being sought for the nation's energy needs, many researchers are starting to warn about the dangers of ignoring environmental realities.

"Many Americans see terrorism as the principal threat to security," Brown said. "But for much of humanity, the effects of water shortages and rising temperatures on food security are far more important issues."