Ground-Water and Surface-Water Flow and Estimated Water Budget for Lake Seminole, Southwestern Georgia and Northwestern Florida By Melinda S. Dalton, Brent T. Aulenbach, and Lynn J. Torak Prepared in cooperation with the Georgia Department of Natural Resources Environmental Protection Division Georgia Geologic Survey Scientific Investigations Report 2004-5073 U.S. Department of the Interior U.S. Geological Survey Cover photograph: Polk Lake, Chattahoochee, Florida, 1950 View looking east along the fixed-crest spillway during construction of Jim Woodruff Lock and Dam. During 2002, the U.S. Army Corps of Engineers and the U.S. Geological Survey participated in a dye-tracing study that found lake water moving through the ground-water system to the Apalachicola River via Polk Lake Spring. Photograph by: U.S. Army Corps of Engineers, archives, Mobile District, Mobile, Alabama Ground-Water and Surface-Water Flow and Estimated Water Budget for Lake Seminole, Southwestern Georgia and Northwestern Florida By Melinda S. Dalton, Brent T. Aulenbach, and Lynn J. Torak Prepared in cooperation with the Georgia Department of Natural Resources Environmental Protection Division Georgia Geologic Survey Atlanta, Georgia Scientific Investigations Report 2004-5073 U.S. Department of the Interior U.S. Geological Survey U.S. Department of the Interior Gale A. Norton, Secretary U.S. Geological Survey Charles G. Groat, Director U.S. Geological Survey, Reston, Virginia: 2004 This report is available on the World Wide Web at http://infotrek.er.usgs.gov/pubs/ For more information about the USGS and its products: Telephone: 1-888-ASK-USGS World Wide Web: http://www.usgs.gov/ Any use of trade, product, or firm names in this publication is for descriptive purposes only and does not imply endorsement by the U.S. Government. Although this report is in the public domain, permission must be secured from the individual copyright owners to reproduce any copyrighted materials contained within this report. Suggested citation: Dalton, Melinda S., Aulenbach, Brent T., and Torak, Lynn J., 2004, Ground-water and surface-water flow and estimated water budget of Lake Seminole, southwestern Georgia, and northwestern Florida, U.S. Geological Survey, Scientific Investigations Report 2004-5073, p. 54. iii Contents Abstract ……………………………………………………………………………………… 1 Introduction …………………………………………………………………………………… 2 Purpose and Scope ……………………………………………………………………… 2 Study Area ……………………………………………………………………………… 4 Physiography …………………………………………………………………………… 4 Climate …………………………………………………………………………………… 5 Previous Studies ………………………………………………………………………… 5 Well and Surface-Water-Station Numbering System …………………………………… 6 Acknowledgments ……………………………………………………………………… 6 Ground Water ………………………………………………………………………………… 7 Hydrogeologic Setting …………………………………………………………………… 8 Hydraulic Characteristics ……………………………………………………………… 8 Overlying Semiconfining Units ……………………………………………………… 8 Upper Floridan Aquifer …………………………………………………………… 9 Lisbon Formation …………………………………………………………………… 9 Ground-Water Levels …………………………………………………………………… 9 Seasonal Fluctuations ……………………………………………………………… 9 Effects of Drought and Pumping …………………………………………………… 10 Surface-Water Influence …………………………………………………………… 10 Surface Water ………………………………………………………………………………… 12 Drainage ………………………………………………………………………………… 12 Streamflow ……………………………………………………………………………… 12 Dams and Navigational Improvements ………………………………………………… 13 Water-Budget Calculations for Lake Seminole ……………………………………………… 14 Precipitation …………………………………………………………………………… 14 Surface Water …………………………………………………………………………… 15 Ungaged Inflow to Lake Seminole ………………………………………………… 16 Error Analysis ……………………………………………………………………… 17 Lake Storage …………………………………………………………………………… 17 Ground-Water Inflow and Lake Leakage ………………………………………………… 18 Estimation of Flow Rates …………………………………………………………… 18 Error Analysis ……………………………………………………………………… 20 Lake Evaporation ………………………………………………………………………… 22 Energy-Budget Method …………………………………………………………… 22 Empirical Equations ………………………………………………………………… 25 Priestley-Taylor Equation …………………………………………………………… 25 Penman Equation …………………………………………………………………… 25 DeBruin-Keijman Equation ………………………………………………………… 25 Papadakis Equation ………………………………………………………………… 25 Georgia Automated Environmental Monitoring Network …………………………… 26 Evaluation of Evaporation Estimates and Methods ……………………………………… 26 Water-Budget Summary ……………………………………………………………………… 27 Water-Budget Error ……………………………………………………………………… 31 Sensitivity Analysis ……………………………………………………………………… 31 iv Summary ……………………………………………………………………………………… 33 References Cited ……………………………………………………………………………… 33 Appendix —Methods and Instrumentation …………………………………………………… 37 Figures 1–2. Maps Showing: 1. Location of study area, boundaries of the lower Apalachicola –Chattahoochee – Flint River Basin, and physiographic divisions of the Coastal Plain Province in southeastern Alabama, northwestern Florida, and southwestern Georgia …… 3 2. Study area, wells, surface-water , and climate stations near Lake Seminole … 5 3. Schematic diagram of the ground-water flow system in the lower Apalachicola– Chattahoochee–Flint River Basin ………………………………………………… 7 4. Correlation chart of geologic and hydrologic units in the lower Apalachicola– Chattahoochee–Flint River Basin ………………………………………………… 8 5. Hydrograph showing seasonal water-level fluctuations in the semiconfining unit (well 09G003) and the Upper Floridan aquifer (well 09F520), 1980–2001 …………… 10 6. Generalized map of the water-level surface of the Upper Floridan aquifer, (A) August 2000 and (B ) July 1962 ………………………………………………… 11 7. The hydrologic cycle for Lake Seminole …………………………………………… 14 8–17. Graphs Showing: 8. Difference in discharge between the Apalachicola River at Chattahoochee, Florida, and Jim Woodruff Lock and Dam ……………………………………… 15 9. Regression defining the stage-volume relation for Lake Seminole …………… 18 10. Lake Seminole ground-water inflow and lake leakage derived from simulated results for the period April 2000 – September 2001 ……………………………… 18 11. Regression showing relation between total solar radiation and observed net radiation at (A ) Cummings Access, Georgia, and (B ) Sneads Landing, Florida … 22 12. Relation between average air temperature and surface-water temperature at Lake Seminole, July 2000 ……………………………………………………… 24 13. Monthly estimates of evaporation computed using the energy budget and empirical equations: (A) Priestley-Taylor, (B) Penman, (C ) DeBruin-Keijman, (D ) Papadakis, and (E ) Georgia Automated Environmental Monitoring Network, April 2000 – September 2001 ………………………………………… 28 14. Percent contribution of Lake Seminole water-budget components …………… 30 15. Monthly average precipitation during the study period compared with long-term average precipitation at climate station in Arlington, Georgia, 1960 – 2002 ……………………………………………………………………… 31 16. Relative sensitivity of the Lake Seminole water budget to component inflow … 32 17. Relative sensitivity of the Lake Seminole water budget to component outflow … 33 A1. Diagram showing (A) Location of climate stations installed over water on Lake Seminole; (B ) climate-station installation at Sneads Landing, Florida, on Lake Seminole; and (C ) schematic of instruments used in overwater installation of climate stations ………………………………………………… 37 A2. Map showing temperature probe arrays in Lake Seminole, Georgia …………… 41 v A3–A4. Graphs Showing: A3. Time-series plot for temperature probe array 1 ………………………………… 45 A4. Plots of seasonal-temperature profiles illustrating spatial temperature differences seasonally on (A ) July 1, 2000, (B ) October 1, 2000, and (C ) January 1, 2001 ……………………………………………………………… 46 Tables 1. Climate data for Arlington, Early County, Georgia, 1959–2000 ……………………… 6 2. Surface-water inflows to Lake Seminole …………………………………………… 13 3. Ungaged inflows to Lake Seminole ………………………………………………… 13 4. Comparison of long-term average (based on 42 years of record, 1959 –2000, Georgia Automated Environmental Monitoring Network, 2002) precipitation to monthly precipitation during the study period ……………………………………… 15 5. Summary of streamflow measurements for substantial ungaged inflows to Lake Seminole ……………………………………………………………………… 16 6. Summary of Cauchy-type boundaries used to estimate flow between the Upper Floridan aquifer and stream channels ……………………………………… 19 7. Summary of surface-water inflows and outflows used in the water and energy budgets and the temperature arrays used to calculate daily average temperatures of surface-water inflows and outflows for energy budget ………… 23 8. Summary of daily temperature arrays used to calculate daily average temperature of surface-water inflow and outflow for the main body of the Lake Seminole and impoundment arms ………………………………………………………………… 23 9. Evaporation rates calculated using the energy budget, those derived from empirical equations, and those values posted to the Georgia Automated Environmental Monitoring Network at http://www.griffin.peachnet.edu/bae/ …… 27 10. Monthly water-budget variables and cumulative error for Lake Seminole ………… 29 11. Average study period percent difference in water budget of Lake Seminole comparing empirical equations, long-term average annual pan evaporation, and the energy budget ……………………………………………………………… 32 A1. Instrumentation of the climate stations installed on Lake Seminole ……………… 38 A2. Monthly statistics for average climate conditions on Lake Seminole ……………… 39 A3. Temperature probe arrays, probe depth, installation data and probe elevation …… 42 A4. Mean, median, minimum, and maximum temperatures for