Influences of Environmental Settings on Aquatic Ecosystems in the Apalachicola- National Water-Quality / Assessment Program / Chattahoochee- Study Units :e Sidney Lot) let Flint River Basin Chattahoochee River basin U.S. Geological Survey Apalachicola River basin Water-Resources Investigations Report 95-4278 The authors appreciate the extraordinary efforts of the editorial and cartography staff of the Georgia District, including Carolyn A. Casteel, Caryl J. Wipperfurth, and Eric A. Steinnagel. Cover: Photograph by Elizabeth A. Frick showing the view of the Apalachicola River at Alum Bluff in the Apalachicola Bluffs and Ravines Reserve, The Nature Conservancy, near Bristol, Florida. INFLUENCES OF ENVIRONMENTAL SETTINGS ON AQUATIC ECOSYSTEMS IN THE APALACHICOLA-CHATTAHOOCHEE-FLINT RIVER BASIN By Carol A. Couch, Evelyn H. Hopkins, and P. Suzanne Hardy U.S. GEOLOGICAL SURVEY NATIONAL WATER-QUALITY ASSESSMENT PROGRAM Water-Resources Investigations Report 95-4278 Atlanta, Georgia 1996 U.S. DEPARTMENT OF THE INTERIOR Bruce Babbitt, Secretary U.S. GEOLOGICAL SURVEY Gordon P. Eaton, Director For additional information, please write to: Copies of this report may be purchased from: District Chief U.S. Geological Survey U.S. Geological Survey Earth Science Information Center Peachtree Business Center Open-File Reports Section Suite 130 Denver Federal Center 3039 Amwiler Road Box 25286, Mail Stop 517 Atlanta, GA 30360-2824 Denver, CO 80225 FOREWORD The mission of the U.S. Geological Survey (USGS) is to assess the quantity and quality of the earth resources of the Nation and to provide information that will assist resource managers and policymakers at Federal, State, and local levels in making sound decisions. Assessment of water-quality conditions and trends is an important part of this overall mission. One of the greatest challenges faced by water-resources scientists is acquiring reliable information that will guide the use and protection of the Nation's water resources. That challenge is being addressed by Federal, State, interstate, and local water-resource agencies and by many academic institutions. These organizations are collecting water-quality data for a host of purposes that include: compliance with permits and water-supply standards; development of remediation plans for a specific contamination problem; operational decisions on industrial, wastewater, or water-supply facilities; and research on factors that affect water quality. An additional need for water-quality information is to provide a basis on which regional and national-level policy decisions can be based. Wise decisions must be based on sound information. As a society, we need to know whether certain types of water- quality problems are isolated or ubiquitous, whether there are significant differences in conditions among regions, whether the conditions are changing over time, and why these conditions change from place to place and over time. The information can be used to help determine the efficacy of existing water-quality policies and to help analysts determine the need for, and likely consequences, of new policies. To address these needs, the Congress appropriated funds in 1986 for the USGS to begin a pilot program in seven project areas to develop and refine the National Water-Quality Assessment (NAWQA) Program. In 1991, the USGS began full implementation of the program. The NAWQA Program builds upon an existing base of water- quality studies of the USGS, as well as those of other Federal, State, and local agencies. The objectives of the NAWQA Program are to: describe current water-quality conditions for a large part of the Nation's freshwater streams, rivers, and aquifers; describe how water quality is changing over time; and improve understanding of primary natural and human factors that affect water-quality conditions. This information will help support the development and evaluation of management, regulatory, and monitoring decisions by other Federal, State, and local agencies to protect, use, and enhance water resources. The goals of the NAWQA Program are being achieved through ongoing and proposed investigations of 60 of the Nation's most important river basins and aquifer systems, which are referred to as study units. These study units are distributed throughout the Nation and cover a diversity of hydrogeologic settings. More than two-thirds of the Nation's freshwater use occurs within the 60 study units and more than two-thirds of the people served by public water-supply systems live within their boundaries. National synthesis of data analysis, based on aggregation of comparable information obtained from the study units, is a major component of the program. This effort focuses on selected water-quality topics using nationally consistent information. Comparative studies will explain differences and similarities in observed water-quality conditions among study areas and will identify changes and trends and their causes. The first topics addressed by the national synthesis are pesticides, nutrients, volatile organic compounds, and aquatic biology. Discussions on these and other water-quality topics will be published in periodic summaries of the quality of the Nation's ground and surface water as the information becomes available. This report is an element of the comprehensive body of information developed as part of the NAWQA Program. The program depends heavily on the advice, cooperation, and information from many Federal, State, interstate, Tribal, and local agencies and the public. The assistance and suggestions of all are greatly appreciated. Information regarding the NAWQA Program is available on the Internet via the World Wide Web. You may connect to the NAWQA Home Page using the Universal Resources Locator (URL) at: <URL:http://wwwrvares.er.usgs.gov/nawqa/nawqa_home.html> iii CONTENTS Abstract 1 Introduction 3 Physical setting 4 Location 4 Physiography 5 Soils 7 Climate 8 Surface-water hydrology 9 Chattahoochee River 9 Flint River 10 Apalachicola River 11 Ground-water hydrology 12 Natural water quality 13 Biological setting 15 Terrestrial habitats 16 Wetland habitats and aquatic vegetation 17 Aquatic fauna 18 Fish fauna 19 Amphibians and reptiles 20 Aquatic invertebrates 21 Cultural setting 21 Population 22 Land cover and use 22 Water use 23 Power generation 25 Navigation 25 Recreation 26 Wastewater discharge 27 Influences of environmental settings on aquatic ecosystems 27 References 33 ILLUSTRATIONS Figures 1-9. Maps showing: 1. Location of the Apalachicola-Chattahoochee-Flint River basin 4 2. Physiographic provinces and districts of the Apalachicola-Chattahoochee-Flint River basin 5 3. Geology of the Apalachicola-Chattahoochee-Flint River basin and adjacent areas 6 4. Major land-resource areas in the Apalachicola-Chattahoochee-Flint River basin 8 5. Soil-mapping units with a high leaching rating in the Apalachicola-Chattahoochee-Flint River basin 9 6. Soil-mapping units with a high runoff rating in the Apalachicola-Chattahoochee-Flint River basin 11 7. Average annual precipitation (1951 -80) in the Apalachicola-Chattahoochee-Flint River basin and adjacent areas 12 8. Average annual runoff (1951 -80) in the Apalachicola-Chattahoochee-Flint River basin and adjacent areas 13 9. Major basin boundaries and location of selected stream-gaging stations in the Apalachicola- Chattahoochee-Flint River basin 14 IV ILLUSTRATIONS Continued Figure 10. Graph showing discharge for water years 1978-92 for the Chattahoochee River at Columbia, Alabama 15 11. Map showing location of mainstem dams and power-generating plants in the Apalachicola- Chattahoochee-Flint River basin 17 Figures 12-18. Graphs showing: 12. Annual hydrographs for Chattahoochee River at Cornelia, Georgia, Chattahoochee River at Norcross, Georgia, Chattahoochee River at Whitesburg, Georgia, and Chattahoochee River at Columbia, Alabama 18 13. Annual hydrograph for Snake Creek near Whitesburg, Georgia 19 14. Annual hydrograph for Peachtree Creek at Atlanta, Georgia 19 15. Discharge for water years 1978-92 for the Flint River at Newton, Georgia 20 16. Annual hydrographs for Flint River at Newton, Georgia, Ichawaynochaway Creek at Milford, Georgia, Spring Creek near Iron City, Georgia 21 17. Discharge for water years 1978-92 for the Apalachicola River at Sumatra, Florida 22 18. Annual hydrograph for Apalachicola River at Sumatra, Florida 22 Figure 19. Map showing generalized outcrop areas for geologic and hydrogeologic units underlying the Apalachicola-Chattahoochee-Flint River basin 24 20. Correlation chart showing generalized geologic and hydrogeologic units in the Coastal Plain of the Apalachicola-Chattahoochee-Flint River basin 25 21. Map showing land use in the Apalachicola-Chattahoochee-Flint River basin, 1972-78 29 22. Map showing location of counties in the Apalachicola-Chattahoochee-Flint River basin 39 23. Graph showing historical and projected population in the Apalachicola-Chattahoochee-Flint River basin, 1970-2010 40 Figures 24-26. Maps showing: 24. Population density (1990) in the Apalachicola-Chattahoochee-Flint River basin 41 25. Silviculture land in the Apalachicola-Chattahoochee-Flint River basin, 1987, 1989, and 1990 43 26. Percent of county in farmland in the Apalachicola-Chattahoochee-Flint River basin, 1987 44 Figures 27-30. Graphs showing: 27. Total areas in farms; and selected categories of cropland, harvested cropland, woodland, and pastureland in the Apalachicola-Chattahoochee-Flint River basin 45 28. Harvested acres of peanuts, corn, soybeans and cotton in the Apalachicola-Chattahoochee-