Status of Water Levels in Aquifers in the Nacatoch Sand of Southwestern and Northeastern Arkansas and the Tokio Formation of Southwestern Arkansas, 2002

摘要

Aquifers in the Nacatoch Sand and Tokio Formation in southwestern Arkansas and the Nacatoch Sand in northeastern Arkansas are sources of water for industrial, public supply, domestic, and agricultural uses. Potentiometric-surface maps were constructed from water-level measurements made in 60 wells completed in the Nacatoch Sand and 48 wells completed in the Tokio Formation during January and February 2002. In northeastern Arkansas, withdrawals from the Nacatoch Sand increased by 784 percent from 1965 to 1990 and decreased by 30 percent from 1990 to 2000. In southwestern Arkansas with-drawals from aquifers in the Nacatoch Sand and Tokio Formation increased by 125 percent and 201 percent, respectively, from 1965 to 1980 and decreased by 93 percent and 81 percent, respec-tively, from 1980 to 2000. Long-term hydrographs were prepared for 13 wells in the study area. Changes in water levels in some wells may be associated with changes in withdrawals from the respective aquifers.