Hydrology of the Claiborne aquifer and interconnection with the Upper Floridan aquifer in southwest Georgia
Scientific Investigations Report 2017-5017
Prepared in cooperation with the Georgia Environmental Protection Division
- Debbie W. Gordon and Gerard Gonthier
The U.S. Geological Survey conducted a study, in cooperation with the Georgia Environmental Protection Division, to define the hydrologic properties of the Claiborne aquifer and evaluate its connection with the Upper Floridan aquifer in southwest Georgia. The effort involved collecting and compiling hydrologic data from the aquifer in subarea 4 of southwestern Georgia. Data collected for this study include borehole geophysical logs in 7 wells, and two 72-hour aquifer tests to determine aquifer properties.
The top of the Claiborne aquifer extends from an altitude of about 200 feet above the North American Vertical Datum of 1988 (NAVD 88) in Terrell County to 402 feet below NAVD 88 in Decatur County, Georgia. The base of the aquifer extends from an altitude of about 60 feet above NAVD 88 in eastern Sumter County to about 750 feet below NAVD 88 in Decatur County. Aquifer thickness ranges from about 70 feet in eastern Early County to 400 feet in Decatur County.
The transmissivity of the Claiborne aquifer, determined from two 72-hour aquifer tests, was estimated to be 1,500 and 700 feet squared per day in Mitchell and Early Counties, respectively. The storage coefficient was estimated to be 0.0006 and 0.0004 for the same sites, respectively. Aquifer test data from Mitchell County indicate a small amount of leakage occurred during the test. Groundwater-flow models suggest that the source of the leakage was the underlying Clayton aquifer, which produced about 2.5 feet of drawdown in response to pumping in the Claiborne aquifer. The vertical hydraulic conductivity of the confining unit between the Claiborne and Clayton aquifers was simulated to be about 0.02 foot per day.
Results from the 72-hour aquifer tests run for this study indicated no interconnection between the Claiborne and overlying Upper Floridan aquifers at the two test sites. Additional data are needed to monitor the effects that increased withdrawals from the Claiborne aquifer may have on future water resources.
Gordon, D.W., and Gonthier, Gerald, 2017, Hydrology of the Claiborne aquifer and interconnection with the Upper Floridan aquifer in southwest Georgia: U.S. Geological Survey Scientific Investigations Report 2017–5017, 49 p., https://doi.org/10.3133/sir20175017.
ISSN: 2328-0328 (online)
Table of Contents
- Hydrologic Conditions 2015–16
- Methods of Investigation
- Claiborne Aquifer Hydrology and Interconnection With the Upper Floridan Aquifer
- Summary and Conclusions
- Selected References
Additional publication details
- Publication type:
- Publication Subtype:
- USGS Numbered Series
- Hydrology of the Claiborne aquifer and interconnection with the Upper Floridan aquifer in southwest Georgia
- Series title:
- Scientific Investigations Report
- Series number:
- Year Published:
- U.S. Geological Survey
- Publisher location:
- Reston, VA
- Contributing office(s):
- South Atlantic Water Science Center
- x, 49 p.
- United States
- Other Geospatial:
- Claiborne Aquifer
- Online Only (Y/N):
- Additional Online Files (Y/N):