Water levels and water quality in the Sparta-Memphis aquifer (middle Claiborne aquifer) in Arkansas, spring-summer 2011

Potentiometric surfaces (2013, 2015), groundwater quality (2010–15), and water-level changes (2011–13, 2013–15) in the Sparta-Memphis aquifer in Arkansas

“…In particular, these maps provide a graphical presentation of water-level data and give an indication of the status of water storage in an aquifer, the economic viability of extracting water, and when compared with past potentiometric-surface maps, information on changes in groundwater storage in time and space. Water-level and water-quality data presented in this report are a continuation of data presented by Kresse and others (2014) and Schrader (2014). Kresse and others (2014) evaluated water-level data from 1921 through 2009, water-quality data from approximately 1950 through 2010, and water-use data from 1965 through 2010.…”

“…Kresse and others (2014) evaluated water-level data from 1921 through 2009, water-quality data from approximately 1950 through 2010, and water-use data from 1965 through 2010. Schrader (2014) discussed Sparta-Memphis aquifer groundwater levels and water quality and presents a 2007-11 water-level-change map. This report presents Sparta-Memphis aquifer potentiometricsurface maps for 2013 (pl.…”

Development of a Numerical Multi-Layered Groundwater Model to Simulate Inter-Aquifer Water Exchange in Shelby County, Tennessee

“…The model area, as shown in Figure 1c and Figure S3 in the Supplementary Material, was chosen to capture all of the well fields in Shelby County as well as pumping centers in nearby neighboring municipalities that may influence flow conditions. The western side of the model was truncated to maintain no-flow conditions in the northwestern corner of the Memphis aquifer as it is perpendicular to the general flow, and to match a groundwater divide [48,68] with a constant head in the southwestern corner, both considered invariant hydraulic boundaries.…”

“…The Memphis aquifer was set to a constant-head along the eastern boundary of the model area (Figure 4) to conform with the predominant flow direction and to introduce water into the system based on regional data presented in Schrader [48] which is consistent with historic water level readings between 2005 and 2016 at the nearby monitoring well Fa:R-002 (Figure 5), indicating an average annual deviation of only 20 cm. The southwestern boundary is also set as a constant head as supported by observations in the nearby wells Ar:C-001 and Ar:H-002 (see Figure 5), and based on a persistent groundwater divide mapped by Schrader [48,68]. The north, south, west, and northwestern boundaries correspond to no-flow conditions as model lines are perpendicular to the regional equipotential lines shown by Schrader [48,68] (See Figure 2a) and they are positioned far enough from the main aquifer stressors as to add or remove significant flow across the system.…”

“…The southwestern boundary is also set as a constant head as supported by observations in the nearby wells Ar:C-001 and Ar:H-002 (see Figure 5), and based on a persistent groundwater divide mapped by Schrader [48,68]. The north, south, west, and northwestern boundaries correspond to no-flow conditions as model lines are perpendicular to the regional equipotential lines shown by Schrader [48,68] (See Figure 2a) and they are positioned far enough from the main aquifer stressors as to add or remove significant flow across the system. The Fort Pillow aquifer was originally modelled with a constant-head boundary at the east, as supported by information from well Fa:R-001.…”