Exploring The Sustainability Of The Ogallala Aquifer

Erin O’BrienBiological & Agricultural Engineering

National Science Foundation - Research Experience for Undergraduates

McNair Scholar’s Program

Kansas State UniversitySummer 2001

Introduction

The Ogallala aquifer lies within the Great Plains region.

This groundwater source is a part of the High Plains aquifer system.• In Kansas the High Plains aquifer system

and the Ogallala aquifer are typically the same.

Western Kansas is a major economic source for Kansas:• 40% of the nation’s packaged beef

comes from within 250 miles of Garden City, and

• Kansas is 2nd in the nation in cattle slaughter and 3rd for red meat production.

“Meeting fundamental human needs while preserving the life-support systems of planet Earth is the essence of sustainable development.” —(Kates, et al. 2001)

Since irrigation from the Ogallala taps ‘fossil’ groundwater there is an issue of sustainability of the current system.

Study Area

My study looked at the High Plains with a focus on SW Kansas.

The Ogallala aquifer:• Underlies 134,000 mi2,• Is the largest body of groundwater in the

U.S.• The porous rock layers were formed ~10

million years ago by fluvial deposition.

--(Guru 2000)

The High Plains aquifer has 3.25 billion ac-ft of water, approximately equivalent to Lake Huron.

30% of the water used for irrigation in the U.S. comes from the High Plains aquifer.

10% percent of the drainable water in the High Plains aquifer underlies Kansas.

The High Plains aquifer faces many different concerns, including purity, quality, quantity, and saturated thickness.

The Ogallala region has many concerns:• ~19% is covered by sand dunes;• Water consumption is 10-40 times recharge• Local precipitation does not affect recharge

Ogallala facts:• Only 15-20% of the water is available

for withdrawal and only 60-80% of this is technologically accessible.

• KGS scientists say it may take 35 years for recharge water to reach the aquifer.

• The water in the Ogallala is fossil water and is only available through groundwater mining.

History

The droughts of the 1930s and 50s made people realize that the climate changes of the region were simply cyclical variations.

Irrigation rapidly expanded following the drought of the 1950s.

By 1972, ~40% of the available groundwater had been consumed.

Technology

In 1896 in Garden City, KS, a centrifugal pump was one of the first attempts at irrigation in Kansas.

Another pump was in use by 1911 in Scott City, KS.

In 1949, center-pivot systems were developed.

Drop tubes & subsurface drip irrigation (SDI) have become common recently.

Rules/Regulations

In 1972 KS passed the GMD Act to: • Regulate groundwater, • Grant drilling permits, and • Ensure old water rights are protected.

Constraints exist on policies that would decrease water availability. Adjustments must be technically, financially, legally, and socially feasible.

Sustainability Issues

Farmers irrigate for many reasons:• To meet a specific crop need;• To increase yearly income; • As a result of success by other irrigators; and• To maintain their water rights.

The number of irrigated acres is declining in all states.

Irrigation offers a climate substitute and enables increased yields.

Top: Feedlot at Dodge City, KS.

Left: Sign for IBP, a packing plant near Garden City, KS.

Recurrent droughts are a hazard for the region.

There were two prolonged droughts in the last century:• In the 1930s and the 1950s.

What will happen when the water is gone?• Two New Jersey scholars have proposed

a “buffalo commons” national park.

The area has already been affected by a decreased flow in the Arkansas River due to diversion and pumping.

It has only recently began to flow again, after a Supreme Court ruling limited

withdrawals.

These pages show graphs indicating:• Predevelopment saturated thickness,• Current saturated thickness,• The amount of groundwater depletion,

and• The number of years of usage

remaining.--Schloss, et al. 2000.

Summary

Can the Ogallala aquifer be sustained?

History shows that farmers are adaptable to a variable climate.

Technological advances have greatly improved water use efficiency.

The current irrigation-based economy can be sustained for several more decades.

We must plan for what will happen when irrigated agriculture and the associated agribusiness economy becomes a thing of the past.

Acknowledgements

Guru, Manjula V., and James E. Horne. "The Ogallala Aquifer.” Kerr Center for Sustainable Agriculture, Inc. <http://www.kerrcenter.com/RDPP/ogallala.htm>. July 2000.

Kates, Robert W., et al. “Sustainability Science.” Science. Vol. 292, 641-642: 27 April 2001.

Kromm, David E., and Stephen E. White, eds. Groundwater Exploitation in the High Plains. Lawrence, Kansas: University Press of Kansas, 1992.

Schloss, Jeffrey A., Robert W. Buddemeier, and Blake B. Wilson, eds. An Atlas of the Kansas High Plains Aquifer. Lawrence, Kansas: Kansas Geological Survey, 2000.

Dr. John Harrington, Jr., Dept. of Geography, Kansas State University

Dr. David E. Kromm, Dept. of Geography, Kansas State University