Potentiometric Surface of the Upper Floridan Aquifer in the Coastal Area of Georgia, September 2000

Effects of sea-level rise and pumpage elimination on saltwater intrusion in the Hilton Head Island area, South Carolina, 2004-2104

“…The model area and grid were designed to set model boundaries at natural hydrologic boundaries where possible, and otherwise to set model boundaries far from the study area to subdue any potential boundary effects on the study area (Provost and others, 2006). The simulated potentiometric surface for the Upper Floridan aquifer in 2000 has regional-scale features and altitudes similar to an estimated potentiometric surface for September 2000 (Peck and McFadden, 2004;fig. 46).…”

“…4B) and is the result of large pumping rates and decreasing transmissivity of the aquifer as it thins toward the Beaufort Arch. Water-level altitudes at the center of the cone of depression in 2000 were below -100 ft (Peck and McFadden, 2004). The cone of depression has "captured" groundwater flow, which, prior to development, may have discharged offshore.…”

“…To the southwest and south of the model area, there are no proximal natural hydrologic boundaries for the Floridan aquifer system because it extends west across Georgia and Alabama and south across Florida. For each node at the top of unit 5 along this boundary, a pressure was calculated from the Upper Floridan aquifer head value estimated from predevelopment, May 1980, May 1998, and September 2000 potentiometric maps others, 1980, 1981;Peck and others, 1999;Peck and McFadden, 2004). A hydrostatic pressure gradient was assumed for each vertical column of nodes, and the corresponding time-independent pressure was calculated for, and specified at, each of the nodes under the top node in unit 5 along that boundary (figs.…”

Effects of decreased ground-water withdrawal on ground-water levels and chloride concentrations in Camden County, Georgia, and ground-water levels in Nassau County, Florida, from September 2001 to May 2003

“…Brown (1984), Spechler (1994), Phelps and Spechler (1997), and Phelps (2001) described the geology and hydrogeology of northeastern Florida. Warren (1944), Johnston and others (1980), Krause and Hayes (1981), Clarke (1987), Peck (1991), Peck and others (1999), and Peck and McFadden (2004) presented maps showing the potentiometric surface of the Upper Floridan aquifer in the coastal area of Georgia. Warren (1944) presented one of the earliest potentiometric surface maps of the Upper Floridan aquifer.…”

Hydrogeology, water quality, and water-supply potential of the Lower Floridan Aquifer, coastal Georgia, 1999-2002

“…3). Water-level data from numerous Upper Floridan wells in the study area were used by previous investigators to document the potentiometric surface at specific time periods in all or parts of the CSSI study area (Warren, 1944;Counts and Donsky, 1963;Hayes, 1979;Johnston and others, 1981;Burtell, 1990;Clarke and others, 1990;Peck, 1991;Ransom and White, 1999;Peck and others, 1999;Peck and McFadden, 2004). The effects of regional declines in water levels were particularly noticeable in the coastal counties of the CSSI study area where artesian flow ceased as water levels, previously above land surface, progressively declined below land surface (Johnston and others, 1981;Krause and Randolph, 1989).…”