Groundwater Irrigation in the Development of the Grand Prairie Rice Industry, 1896-1950

ARKANSAS PRODUCES MORE RICE than any other state in the U.S., being responsible for slightly less than half of the total number of acres harvested nationwide.1 Much of the state's rice is grown in the Grand Prairie of east-central Arkansas, where the crop serves as the centerpiece of the region's economy. An extremely water-intensive crop, rice in Arkansas requires approximately thirty-three inches of water in a growing season, but the Grand Prairie receives an average of only eleven inches of rain. The remainder must be secured from other sources. As a result, rice production in the Grand Prairie has always been dependent upon irrigation, primarily from groundwater. The necessity of raising groundwater has shaped the development of the industry in the Grand Prairie from its inception and has taken a toll on the region's water resources. Groundwater depletion has been a concern since as early as the 1920s. This essay hopes to elucidate some of the ways in which groundwater and groundwater irrigation have affected the Grand Prairie's rice industry over time and conversely how the development of the industry has altered the region's groundwater conditions. It will thus concentrate on aspects of the industry's history that have often been overlooked in favor of rice cultivation's social dimensions and consider hydrological systems not just as resources awaiting exploitation or as simple constraints on production but as variables whose roles and effects can change over time. The primary source of irrigation water in the Grand Prairie is the Mississippi River Valley Alluvial Aquifer, a part of the Gulf Coastal Plain Aquifer System. The aquifer underlies portions of seven states (Illinois, Kentucky, Tennessee, Missouri, Arkansas, Mississippi, and Louisiana) and has a total area of about 32,000 square miles. It consists of water-bearing sands and gravels, mainly from the Pleistocene, that were deposited by the Mississippi and Ohio Rivers and their tributaries. The aquifer has an average thickness of around 100 feet, gradually changing from fine grained at the top to mainly coarse-grained material at the bottom. Above the aquifer is the Mississippi River Valley confining unit, a layer of clay, silt, and fine sand that is much less permeable to water. This layer, commonly referred to as the clay cap, is thickest in the Grand Prairie, where it is consistently greater than fifty feet. This sub-soil clay layer inhibits irrigation water from draining out of the flooded rice fields, a condition that is advantageous for rice production (though it complicates the task of draining rice fields after the growing season). Before extensive pumping began, the Alluvial Aquifer exhibited artesian conditions in all or most of the Grand Prairie, which means water levels observed in wells were several feet higher than the aquifer itself. In this region, groundwater discharged from the aquifer chiefly to rivers, particularly the White, Arkansas, Little Red, and Bayou Meto. Recharge sufficient to offset the losses was supplied by rainfall and, to a lesser extent, through interaction with the underlying rock. Because of the location of the major rivers to the south and east, the general direction of groundwater flow was towards the southeast, mirroring the general slope of the land surface. Rice cultivation in the Grand Prairie is usually traced to W. H. Fuller, who in 1895 had moved from Nebraska to the vicinity of Carlisle, Lonoke County.3 He was one of a large number of northern and midwestern farmers attracted to the sparsely populated Grand Prairie by low land prices and an accessibility newly afforded by railroad lines. In August 1896, Fuller and a companion, Hewit Puryear, traveled via horse and wagon to Louisiana for a hunting trip. Along the way, the pair encountered rice fields near the town of Crowley in southern Louisiana. Fuller recalled in 1909 that he paused there for several hours to observe the rice fields and pumping plant, the first he had ever seen. …