Dealing with the issue of water scarcity.

Water. It is our earth's most precious resource, essential to human life. While there is no shortage of water on earth, there is indeed, an increasing scarcity of fresh water relative to the needs of our society. In fact, severe shortages already exist in key regions of the world, such as Asia and the Middle East. The United Nations has declared 2003 "The Year of Fresh Water."

Domestically, evidence of the scarcity of fresh water is becoming much more apparent. The recent stories on the impact of the drought in the West and well moratoriums are a vivid reminder of the growing impact the drought has caused here in the United States.

As water becomes scarcer, water management must improve. The industrial revolution, the massive growth in human population during the 20th century and subsequent technological advances have created greater demands on our fresh water supply, but have also enabled us to control the natural hydrological cycle to better conserve our water. Despite the proven power of technology to address most challenges, there is little question that the water demand of our thirsty cities, factories and farms will soon exceed available water supply.

I recently presented a special white paper on the scarcity of fresh water to the World Water Forum in Kyoto, Japan. Thousands of the world's leading experts on water participated in this forum, discussing a wide variety of methods and theories to deal with the decline of fresh water.

As the largest consumer of fresh water, using roughly 70 percent of all human water withdrawals, agriculture has a special role to play in the future of water management. We must deal with the unique challenge agriculture faces in balancing the need to continue to produce more food to feed the growing human population, while also becoming more efficient in the use of fresh water to grow crops. Finding a solution to this delicate balance is essential to our future.

In determining how to deal with this situation, we first need to look at several important facts.

* The global human population will continue to grow, reaching between 9 and 10 billion people by the year 2050.

* Global economic development will mean a greater demand for calorie consumption per capita, particularly in the third world.

* Experts believe there is limited additional dry land available for farming. While non-irrigated crop yields are increasing, it will not be enough to meet future demands for food.

* There will continue to be an increase in irrigated land for food production. Additional irrigation will make even more demands for fresh water.

It seems clear that as we look to the future, we must focus attention on finding the most efficient systems to raise crops and protect fresh water supplies. And a closer look at the facts makes it clear that agriculture has the greatest potential for solving the problem of global water scarcity.

For centuries, most of the world's farmers have used the traditional gravity flow or "flood" irrigation method. This system allows water to flow down a crop row until it reaches the other end. While traditional flood irrigation can be effective in watering crops, studies show this method is only 40 to 50 percent efficient in the use of water. Some crops receive far more water than required, others far less.

Today's modern irrigation systems, whether center-pivot or subsurface drip systems, have proven to be 95 percent water efficient when properly managed. And that can result in literally millions of gallons of fresh water being saved each year by each farmer. However, switching from a flood to mechanized irrigation system costs money, which is also in scarce supply among many in agriculture.

In Nebraska, there are 3.6 million acres of farmland that use center-pivot irrigation, a modern, efficient system that uses up to 65 percent less water than siphon tubes, gated pipe or any other manual method. Still, more than 2 million acres of Nebraska farmland use flood irrigation. Those farmers must be encouraged to convert to modern irrigation to help provide a potential answer to the problem of global water scarcity.

California still has over 5.8 million acres of flood irrigation, despite the water wars there between farms and cities. Texas has 2 million acres of flood irrigation. Idaho has nearly a million acres. And the list goes on.

In the past two years, our federal government has initiated programs to encourage farmers to switch from traditional flood irrigation to modern irrigation systems. The demand for this federal money far exceeds the funds available. In certain parts of the world, governments are now considering providing support and incentives to help their farmers convert to modern irrigation systems. Mexico and Brazil are two leading countries providing effective incentives to farmers to invest in modern, efficient agricultural irrigation.

In addition to improving the equipment itself, we must also do a better job of training our farmers and farm managers to use water effectively. Poor management can easily offset most of the water savings opportunity provided by improved equipment. Today technologies such as ET (Evapo-Transpiration) models, weather stations and soil moisture sensing can already make the task of efficiently managing water resources easier.

Employing the modern technology available for water-efficient irrigation is clearly a key to overcoming the global challenges of water scarcity. Irrigation is the primary consumer of water on Earth, and modern irrigation can provide a potential answer to the problem of global water scarcity. By extending government incentives that will encourage farmers to switch to more effective and efficient irrigation systems, our world can take an important step forward in the effort to preserve fresh water for future generations.

Thomas D. Spears is president of Valmont's Irrigation Division, the world's leading manufacturer of mechanized irrigation equipment and technology. Valmont's products enhance food production, conserve water and protect natural resources in more than 100 countries.

Send suggestions for editorials to Mary, Shepherd ([e-mail])