Water Levels and Selected Water-Quality Conditions in the Mississippi River Valley Alluvial Aquifer in Eastern Arkansas, 2008

摘要

During the spring of 2008, the U.S. Geological Survey, in cooperation with the Arkansas Natural Resources Commission and the Arkansas Geological Survey, measured 670 water levels in 659 wells completed in the Mississippi River Valley alluvial aquifer in eastern Arkansas. Groundwater levels are affected by groundwater withdrawals resulting in potentiometric- surface depressions. In 2008, the lowest water-level altitude was 69 feet above National Geodetic Vertical Datum of 1929 in the center of Arkansas County. The highest waterlevel altitude was 288 feet above National Geodetic Vertical Datum of 1929 in northeastern Clay County on the west side of Crowleys Ridge. Two large depressions in the potentiometric surface are located in Arkansas, Lonoke, and Prairie Counties and west of Crowleys Ridge in Craighead, Cross, Lee, Monroe, Poinsett, St. Francis, and Woodruff Counties.