The Lower Mississippi Alluvial Valley, often referred to as the Delta, is famously wet, known for big muddy rivers, oxbow lakes crowded with cypress knees, and flooded fields stretching as far as the eye can see.
But as strange as it might sound, the Delta is drying up. If this trend is not reversed, it will soon become a crisis for local agriculture, and for all of the many communities that depend on it.
Looks can be deceiving. On the surface, the home of catfish and the blues appears as drenched as ever. But below ground, the deep water reserve, or acquifer, upon which farming in the Mississippi Delta has depended for over a century, has dropped to alarming levels and in several places is nearly empty.
The Mississippi River Valley Alluvial Acquifer (MRVAA) is a water-bearing mixture of sand and gravel that spreads for about 32,000 square miles underneath Louisiana, Arkansas, Mississippi, Tennessee, Kentucky, and Missouri. Most of it is underneath east Arkansas, and it provides farmers in this area with over 90 percent of the water they use for crop irrigation.
The water in the MRVAA is not evenly distributed. Along the banks of Arkansas' major rivers, it is continuously replenished, and so remains nearly full. But as you move inland the water level rapidly decreases. In many places it holds less than 50 percent of its original volume, and in some critical areas, such
as in the central Grand Prairie and in Poinsett County west of Crowley's Ridge, it is closer to 5 percent. Moreover, according to scientists with USDA and Arkansas State University, the rate of depletion is increasing and the critical areas are expanding.
To understand how this happened, it helps to start at the beginning. Long before humans arrived in the Americas, the entire region, from Louisiana to southern Illinois, was submerged and formed a shallow bay of the Gulf of Mexico. Geologists still refer to it as the Mississippi Embayment.
After the waters receded it existed for thousands of years as a vast, howling wilderness, a swamp forest teeming with now-vanished biodiversity--panthers and red wolves, subtropical parakeets, innumerable reptiles and insects, and the ivory billed woodpecker.
Starting in the early 1800s, then picking up in earnest after the Civil War, American settlors began what is known as "the Big Cut." Lumber mills, and whole villages centered around them, sprang up along the banks of the many rivers and gradually worked their way inland. For a few decades, lumber barons made fortunes felling and shipping across the country millions of oak, gum, and especially bald cypress trees, which once towered above the Delta as mighty as California redwoods.
After the logging camps came the land levelers, and after the levelers came the farmers. What they found was some of the best row-cropping ground in the country, flat as a pan, rich with millenia of Mississippi River sediment and organic matter, and blessed with a seemingly inexhaustible supply of water.
Rice, which is not native to the United States, was first introduced to Arkansas in the early 1800s. At the time, the only known method of cultivation was continuous flooding. Despite ample surface water, Arkansas farmers didn't think they could depend on it for large-scale rice production away from the major rivers, and they didn't try. Cotton was king, and it kept farmers busy.
Then, in 1902, William Fuller of Lonoke County invested in a system of wells and pumps and demonstrated how plentiful and accessible the water underneath the ground was.
As the 20th century began, two things happened at once: It became clear that the acquifer underneath east Arkansas could provide enough water to flood rice fields on a massive scale, and hundreds of thousands of acres of rich, flat land became available for cultivation. Since then, Arkansas has been the largest rice-producing state in the country.
Local farmers in the Grand Prairie began expressing concern about depleting the acquifer as early as 1916, when they realized they were having to drill deeper and deeper every year to find sufficient water to flood their fields. Nevertheless, withdrawals for irrigation increased by more than tenfold from 1950 to 2010, and have continued increasing to this day.
This is a crisis in the making. The Arkansas agricultural industry, which accounts for one in six jobs in the state, is built upon a vanishing resource. Moreover, the environmental damage could be immense. Among other things, geologists are concerned that sink holes could open in unpredictable locations as the ground shifts, and that rivers and streams could drop and even dry up entirely as their water gets diverted to empty spaces underground.
Such nightmare scenarios have gotten the attention of state and federal authorities, who have created a variety of tax incentives and subsidies to encourage farmers to conserve water. But since farmers cannot simply stop farming in order to conserve water, better practices must also be developed.
Thankfully, a variety of scientists and farmers across east Arkansas are working on this problem. Many of the solutions they have developed involve making greater use of surface water to relieve stress on the acquifer, also known as "groundwater."
Perhaps the most ambitious of these surface water solutions are the Bayou Meto Basin Project and the White River Irrigation Project, also called the Grand Prairie Demonstration Project, which were created by a consortium of government and nonprofit entities.
These projects involve the diversion of water from the Arkansas and the White rivers into hundreds of miles of specially built canals, channels, and ultimately pipes and reservoirs for farmers to draw on. Construction is not complete, but when it is they should be capable of providing enough surface water to irrigate hundreds of thousands of acres of farmland in some of the driest parts of the Delta.
Still, though these marvelous feats of engineering are sorely needed, at their full extent they will reach approximately 12 percent of irrigated cropland in Arkansas. There are two smaller projects in operation in Lonoke and Pope counties, and as many as five additional ones are planned.
But even if all of these projects are completed, they do not seem likely to reach half or even a third of the land that needs water, and thus they are not a complete solution to the problem of acquifer depletion.
Farmers don't have to rely on grand projects, though, to make better use of surface water. In recent years, irrigation reservoirs that store rainwater, and tailwater recovery ditches that recirculate field runoff, have grown in popularity.
One of the most successful farmers at utilizing these methods is Terry Dabbs, who farms approximately 3,000 acres in Arkansas County, and does it with 100 percent surface water. His family started building ditches and reservoirs decades ago as they watched their well water drop year after year. By the time it dried up completely, they had no need for it.
"We were lucky," says Dabbs. "We had land that was ideal for these things, and didn't have to take any out of production. But for farmers who have to sacrifice cropland, it could be too expensive."
USDA provides subsidies and technical assistance for farmers who are willing to shift to surface water. But the government can only do so much. The decision has to be made by individual farmers, and if surface water is too expensive or too distant, they won't use it.
Developing new sources of water is, however, only one side of water conservation. The other side is improving efficiency, where there is also much that can be done. Rice is not the only crop that uses groundwater, but on account of continuous flooding, it is by far the most wasteful.
Though continuous flooding was long believed to be the only possible method of cultivation, this is no longer the case. Largely thanks to the work of the University of Arkansas Rice Research and Extension Center in Stuttgart, Arkansas farmers have new options.
Among these are alternative wetting and drying, which allows rice fields to dry completely for several days before reflooding, and "row rice," which treats rice like any other row crop, irrigating it in the furrows between the rows. Both methods use dramatically less water to produce similar yields to conventional flooding systems.
A further innovation, which is beginning to make waves in Arkansas, is called system of rice intensification, or SRI.
SRI is an adaptable practice that was first developed in Madagascar in 1986 and has since spread across the global South. It involves spacing rice seeds farther apart from one another, which strengthens root systems, and it mingles well with regenerative practices like cover crops, organic fertilizer, and integrated pest management. As these regenerative practices encourage the growth of deep underground root networks, they improve the ability of soil to hold water, which reduces the need for irrigation.
Adam Chappell, from Woodruff County, has been developing SRI for years, and now applies it on approximately 1,200 acres. As the president of the Arkansas Soil Health Alliance, Chappell is at the forefront of regenerative farming in the Delta.
Though each individual irrigation and cultivation technique can be done in isolation, and doing so greatly advances the cause of water conservation, even more can be accomplished by combining techniques. Cutting-edge research on this is underway.
At the University of Arkansas' new Northeast Rice Research and Extension Center (NERREC) in Harrisburg, which just opened in May, scientists are combining row-rice cultivation with surface water recirculation, and at a new research farm in nearby Cherry Valley run by Delta Conservation, a regenerative agriculture nonprofit, scientists from the Rodale Institute and the University of Arkansas are collaborating, with the assistance of Adam Chappell, to combine SRI in a row-rice format with surface water recirculation.
Across the Delta, people are rising to this monumental challenge because the evidence is clear -- we are facing a water crisis. Business as usual is a luxury we can no longer afford. If Arkansas wants to remain the powerhouse of American rice production, the only choice we have is progress.
Todd C. Watson is the executive director of Delta Conservatiom, an Army JAG officer, a former journalist, and an attorney.