Agriculture is booming on the Texas High Plains, but the prosperity may be short-lived. The Ogallala Aquifer, the region’s primary irrigation water source, is receding fast, and experts predict the demand for water will exceed the available supply in 10-20 years.

“It’s a huge issue,” says Vivien Allen, forage agronomist at Texas Tech University in Lubbock. “You can’t be out here and not be pas- sionate about it, because it’s writing the whole future of this region.”

Allen is project coordinator for research comparing the water-use efficiency of various cropping sys- tems. Begun in 1997, the work has found that systems that include for- ages, especially warm-season perennial grasses, can save signifi- cant amounts of water.

In the last five years, however, dairies have moved into the region in a big way. About 485,000 dairy cows are now in an area that extends just across the borders of New Mexico and Oklahoma, and that number is expected to double in the next four to five years. The dairy expansion, along with five planned ethanol plants, makes saving the aquifer an ominous challenge, says Allen.

Two things that need to happen, she’s convinced, are for the dairy growth to end and for existing dair- ies to find less-thirsty alternatives to corn for silage production.

Said to be the largest contiguous area of intensive agricultural produc- tion in the world, the Texas High Plains encompass most of north- western Texas, including the pan- handle. The region currently produc- es 20-25% of the total U.S. cotton crop, about 25% of the fed cattle and is rapidly becoming a major dairy area, as well.

“About 40% of the economy of this region comes from agriculture,” Allen points out. “Agriculture is what it’s all about out here.”

Without irrigation, however, much of that revenue would be lost. Irrigators there pull water from the southern end of the Ogallala, a vast underground reservoir that stretches northward to the Dakotas. Once thought to be an inexhaustible water supply, the aquifer is dropping by almost 1’ per year in the region, and agriculture gets most of the blame. Roughly 95% of the water pumped is used for irrigation, says Allen.

According to her, the problem was identified in the 1970s, when farmers discovered that their irrigation wells were pumping less water than before. They began adopting more efficient irrigation methods, such as low-energy precision application (LEPA) and subsurface drip systems. That saved vast amounts of water, but as more and more wells were drilled, the gains were erased and the drawdown resumed, she reports.

Modern irrigation systems are 95% efficient, so future water sav- ings will have to come from other means. Allen says forages will play a key role. Interest in grazing is on the upswing, with cattle spending less time in feedlots and more time on grass. Cow-calf operations also are increasing in number. Perennial grasses suck up much less water than row crops, and those opera- tions are “holding right in there with cropping systems” in terms of profit- ability, she says.

Her research team has shown that integrated crop-livestock sys- tems use less water and nitrogen fertilizer than monoculture cotton, and also are more profitable at yields representative of the area. That is being verified in a $6.2 mil- lion demonstration project compar- ing water use and economics of vari- ous cropping systems at 26 sites owned by 21 producers.

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