Ground-Water Data Network

Arkansas is the fourth largest user of ground water in the United States. Since the 1920’s, ground-water withdrawals have increased while water levels have declined. Long term water-level records are needed to evaluate the effects of climatic variations on the recharge and discharge from ground-water systems and are necessary in the construction and calibration of accurate ground-water flow models to allow prediction of future conditions. The purpose of the ground-water data network study is to collect hydrogeologic and water-level data sufficient to provide a long-term database so that the general response of the hydrologic system to natural climatic variations and induced stresses is known and potential problems can be defined for management of the resource.

Photograph of center pivoit irrigation system in operation.

The study collects and maintains water levels from the U.S. Geological Survey and State and County agencies. Several reports are produced each year that show water-level altitudes which are used to construct potentiometric-surface maps that define the water-level depressions and the direction of water flow within the aquifer. These reports also present continuous and long-term water-level data that show rates of rise/decline through time. Geophysical logging techniques are performed on selected wells to define the depth and thickness of various aquifers. Aquifer tests are conducted to provide storage and transmissivity coefficients that describe the amount of water available and the rate of flow within the aquifer. Ground-water quality samples are collected to define the potential uses for water and indicate changing conditions within the aquifer.

Publications
	Scientific Investigations Report 2008-5149 Summary of Aquifer Test Data for Arkansas--1940-2006, by Aaron L. Pugh
	Scientific Investigations Report 2008-5137 Potentiometric Surface of the Ozark Aquifer in Northern Arkansas, 2007, by Aaron L. Pugh
	Scientific Investigations Report 2007-5218 Potentiometric Surfaces and Water-Level Trends in the Cockfield and Wilcox Aquifers of Southern and Northeastern Arkansas, 2006, by T.P. Schrader
	Scientific Investigations Report 2007-5029 Status of Water Levels and Selected Water-Quality Conditions in the Sparta-Memphis Aquifer in Arkansas and the Status of Water Levels in the Sparta Aquifer in Louisiana, Spring 2005, by T.P. Schrader and J.S. Jones
	Scientific Investigations Report 2007-5024 Status of Water Levels in Aquifers in the Nacatoch Sand of Southwestern and Northeastern Arkansas and the Tokio Formation of Southwestern Arkansas, February 2005, by T.P. Schrader
	Scientific Investigations Map 3014 Potentiometric Surface in the Sparta-Memphis Aquifer of the Mississippi Embayment, Spring 2007, by T.P. Schrader
	Fact Sheet 2007-3102 Monitoring of Sparta Aquifer Recovery in Southern Arkansas and Northern Louisiana, 2003.07, By David A. Freiwald, U.S. Geological Survey, and Sherrel F. Johnson, Union County Water Conservation Board
	Scientific Investigations Report 2006-5128 Status of Water Levels and Selected Water-Quality Conditions in the Mississippi River Valley Alluvial Aquifer in Eastern Arkansas, 2004, by T.P. Schrader