Effects of aquifer heterogeneity on ground-water flow and chloride concentrations in the Upper Floridan aquifer near and within an active pumping well field, west-central Florida

Abstract

11-12. Maps showing: 11. Specific capacity data for wells at the Eldridge-Wilde well field by final specific capacity, and final specific capacity normalized for length of open hole. .. .. .. .. .. .. 12. Selected wells at the Eldridge-Wilde well field showing dates of well construction and wells that were deepened from original depth or acidized to increase production, and final well depths and pumping capacity (2002) .

Thermal Imaging of the Waccasassa Bay Preserve: Image Acquisition and Processing

“…Groundwater was lowered up to 15 ft in a 15-mi 2 region around the Florida Barge Canal in 1969, with a concomitant rise in the location of the freshwater/saltwater interface where groundwater levels had been lowered (Faulkner, 1973). Similar saltwater intrusion, with saltwater moving along preferential flow paths, was found in Pinellas County in association with groundwater levels lowered by drawdown from water-supply fields (Tihansky, 2004). Shaban and others (2005) describe reverse flows (from the sea to inland areas) where karst conduits became routes for seawater intrusion, notably in the vicinity of overexploitation of a coastal aquifer.…”

“…The Ocala Limestone is an important aquifer-bearing unit, due to enhanced porosity, cavernous flow systems, and permeable composition (Scott, 1992;Coultas and Hsieh, 1997). Permeable layers and dissolution features facilitate flow along preferred pathways (Budd and Loizeaux, 1997;Kindinger and others, 2000;Tihansky, 2004). The FAS is under sufficient pressure, as it flows through the Ocala Limestone, to emerge or discharge through terrestrial springs such as Manatee, Big and Little, and Wekiva Springs ( fig.…”

“…Primary porosity varies from high to low transmissivity within the sedimentary layers (facies) of the Ocala Limestone, each of which may conduct or occlude the flow of water (Loizeaux, 1995). Diagenesis, primarily in the form of dolomitic limestone, can reduce porosity in some areas, and porosity may be enhanced by secondary features such as fractures, fault lines, discontinuities, sinkholes, and dissolution conduits (Loizeaux, 1995;Tihansky, 2004). Groundwater and seawater move horizontally and vertically along preferential flow paths where change to the hydraulic gradient can produce mixing near the coast (Lewelling and others, 1998;Kindinger and others, 2000;Tihansky, 2004).…”

“…Flow near the coast is thus a function of sea level, tides, and groundwater levels in the aquifer (Coultas and Hsieh, 1997;Cable and others, 1997). Seawater flows inland through existing dissolution channels during periods of low groundwater levels in a process called reverse flow (Tihansky, 2004;Fleury and others, 2007). Groundwater was lowered up to 15 ft in a 15-mi 2 region around the Florida Barge Canal in 1969, with a concomitant rise in the location of the freshwater/saltwater interface where groundwater levels had been lowered (Faulkner, 1973).…”

“…Diagenesis, primarily in the form of dolomitic limestone, can reduce porosity in some areas, and porosity may be enhanced by secondary features such as fractures, fault lines, discontinuities, sinkholes, and dissolution conduits (Loizeaux, 1995;Tihansky, 2004). Groundwater and seawater move horizontally and vertically along preferential flow paths where change to the hydraulic gradient can produce mixing near the coast (Lewelling and others, 1998;Kindinger and others, 2000;Tihansky, 2004). Kohout (1977) hypothesized upwelling of recirculated and geothermally heated seawater along the central axis of the Floridan Plateau.…”