Ground water in the Middle Arkansas River basin occurs in consolidated rocks and unconsolidated deposits. Wells for domestic and stock supply generally can be drilled successfully in consolidated rocks. Wells for large-scale municipal, industrial, and irrigation supplies generally are successful in areas underlain by saturated unconsolidated deposits of sand and gravel.
Unconsolidated deposits in the basin receive about 2 million acre-feet of recharge annually, and about 84 million acre-feet of water is in temporary storage in the deposits. In 1968 and 1969 about 270,000 acre-feet of ground water was withdrawn annually for all purposes. Of the total withdrawn, about 167,000 acre-feet was applied for irrigation of about 122,000 acres of cropland. Total annual ground-water withdrawals for irrigation may be 1 million acre-feet by the year 2000.