GEORGIA RIVERS: AN INITIAL ASSESSMENT August 10, 1998 Honorable Zell Miller, Governor Jerry McCollum, Chairman RiverCare 2000 Coordinating Committee Lonice C. Barrett, Commissioner Georgia Department of Natural Resources Harold Reheis, Director Environmental Protection Division Georgia Department of Natural Resources Alan Hallum, Study Manager Chief, Water Protection Branch Environmental Protection Division Georgia Department of Natural Resources 205 Butler Street, SE Suite 1058-E Atlanta, Georgia 30334 GEORGIA BOARD OF NATURAL RESOURCES Mr. Ben G. Porter, Macon Chairman Mr. Thomas W. Wheeler, Jr., Duluth Vice-Chairman Mrs. Sara S. Clark, Alpharetta Secretary Mr. Joe E. Beverly, Thomasville Mr. James E. Butler, Jr., Columbus Mr. Donald J. Carter, Gainesville Mr. J. D. Caswell, Norcross Mr. Bill M. Gilbert, Summerville Mr. Lamond Godwin, Atlanta Mr. Jim Langford, Calhoun Mr. Walter McNeely, Brunswick Mr. Jamie Reynolds, Greensboro Mr. Ben Seay III, Conyers Mr. Glenn E. Taylor, Atlanta Mr. Reese Thompson, Vidalia John R. Williams, Covington RIVERCARE 2000 COORDINATING COMMITTEE Mr. Jerry McCollum, Conyers Committee Chairman President, Georgia Wildlife Federation Honorable Crandle Bray, Jonesboro Chairman, Clayton County Commission Honorable Al Crace, Athens Manager, Athens-Clarke County Mr. Wayne Dollar, Macon President, Georgia Farm Bureau Federation Mr. John Godbee, Savannah Manager, Environmental Engineering, Forest Resources Group, Union Camp Corporation Mr. Bob Izlar, Norcross Executive Director, Georgia Forestry Association Ms. Tavia McCuean, Atlanta Vice President and State Director, The Nature Conservancy of Georgia Mr. E. R. Mitchell, Atlanta President, E. R. Mitchell & Company, Inc. Dr. William H. Murdy, Oxford Dean and CEO, Oxford College of Emory University Mr. Rob Olszewski, Atlanta Director of Forest Resources, Georgia-Pacific Corporation Ms. Suzanne Williams, Atlanta Government Affairs Director, Home Builders Association of Georgia i BLANK PAGE ii TABLE OF CONTENTS INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 USING THE ASSESSMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 AGRICULTURAL RESOURCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 BOTANICAL RESOURCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 CULTURAL RESOURCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 ECONOMIC RESOURCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 EDUCATIONAL RESOURCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 FISH RESOURCES-- ECOLOGICALLY IMPORTANT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47 FISH RESOURCES-- RECREATIONAL AND COMMERCIAL . . . . . . . . . . . . . . . . . . . . . . . . 51 FLOOD-PLAIN RESOURCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57 FOREST RESOURCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62 GEOLOGICAL RESOURCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67 RECREATIONAL BOATING RESOURCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75 SCENIC RESOURCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80 WATER-QUALITY RESOURCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85 WATER-SUPPLY RESOURCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89 WILDLIFE RESOURCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95 SELECTED BIBLIOGRAPHY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100 iii LIST OF TABLES RIVER SEGMENTS BY COMPOSITE CLASS AND RIVER BASIN . . . . . . . . . . . . . . . . . . . . 11 AGRICULTURAL RESOURCES--RATING SUMMARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 BOTANICAL RESOURCES--RATING SUMMARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 CULTURAL RESOURCES (ARCHAEOLOGICAL)-RATING SUMMARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 CULTURAL RESOURCES (HISTORIC STRUCTURES)-RATING SUMMARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 ECONOMIC RESOURCES--RATING SUMMARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 EDUCATIONAL RESOURCES--FACILITIES AND PROGRAMS . . . . . . . . . . . . . . . . . . . . . . 43 FISH RESOURCES (ECOLOGICALLY IMPORTANT)-RATING SUMMARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 FISH RESOURCES (RECREATIONAL AND COMMERCIAL)-RATING SUMMARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56 FLOOD-PLAIN RESOURCES--RATING SUMMARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61 FOREST RESOURCES--RATING SUMMARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66 GEOLOGICAL RESOURCES--RATING SUMMARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74 RECREATIONAL BOATING RESOURCES--RATING SUMMARY . . . . . . . . . . . . . . . . . . . . . 79 SCENIC RESOURCES--RATING SUMMARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84 WATER-QUALITY RESOURCES--RATING SUMMARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88 WATER-SUPPLY RESOURCES--RATING SUMMARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94 WILDLIFE RESOURCES--RATING SUMMARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99 iv LIST OF FIGURES MAP 1: RIVER SEGMENTS, BY COMPOSITE CLASS AND RIVER BASIN . Following p. 11 MAP 2: AGRICULTURAL RESOURCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . Following p. 17 MAP 3: BOTANICAL RESOURCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Following p. 24 MAP 4A: CULTURAL RESOURCES (ARCHAEOLOGICAL) . . . . . . . . . . . . . . Following p. 32 MAP 4B: CULTURAL RESOURCES (HISTORIC STRUCTURES) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Following p. 34 MAP 5: ECONOMIC RESOURCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Following p. 40 MAP 6: EDUCATIONAL RESOURCES--FACILITIES AND PROGRAMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Following p. 46 MAP 7: FISH RESOURCES (ECOLOGICALLY IMPORTANT) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Following p. 50 MAP 8: FISH RESOURCES (RECREATIONAL AND COMMERCIAL) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Following p. 56 MAP 9: FLOOD-PLAIN RESOURCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Following p. 61 MAP 10: FOREST RESOURCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Following p. 66 MAP 11: GEOLOGICAL RESOURCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Following p. 74 MAP 12: RECREATIONAL BOATING RESOURCES . . . . . . . . . . . . . . . . . . . Following p. 79 MAP 13: SCENIC RESOURCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Following p. 84 MAP 14: WATER-QUALITY RESOURCES . . . . . . . . . . . . . . . . . . . . . . . . . . . Following p. 88 MAP 15: WATER-SUPPLY RESOURCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . Following p. 94 MAP 16: WILDLIFE RESOURCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Following p. 99 v ACKNOWLEDGMENT OF MEMBERS OF RIVER ASSESSMENT TEAM DNR Coordinating Group Team Coordinator: Information Consultant: Report Editor: Alan Hallum Hillrie M. Quin Harvey G. Young Executive Support: Report Graphic Designer and Proofreader: Sharon Frank Debi Kirkland Work-Group Chairs Agricultural Resources: Botanical Resources: Cultural Resources: Economic Resources: Educational Resources: Fisheries Resources: Forestry Resources: Tommy Gray Tom Patrick Richard Cloues Paul Burks Laurie Hawks Byron Freeman Frank Green Geological Resources: Recreational Resources: Scenic Resources: Water Quality: Water Resources: Wildlife Resources: GIS Support: Earl Shapiro Alicia Soriano Jon Ambrose Mork Winn Gail Cowie Carroll Allen Hillrie M. Quin Work-Group Members Agricultural Resources: Tommy Gray, Georgia Department of Agriculture, Atlanta Doug Jones, Georgia Department of Agriculture, Atlanta Louis Justice, U.S. Department of Agriculture--Natural Resource Conservation Service, Athens Jimmy Bramblett, U.S.D.A.--Natural Resource Conservation Service, Athens Reggie Thackston, DNR--Wildlife Resources Division, Forsyth Botanical Resources: Steve Bowling, Golder and Associates (environmental consultants), Atlanta Katherine Kirkman, Joseph Jones Ecological Research Center, Newton Tom Patrick, DNR--Wildlife Resources Division, Social Circle Charles Wharton, University of Georgia (retired), Clayton Cultural Resources: Pratt Cassity, University of Georgia--Office of Preservation Services, Athens Richard Cloues, DNR--Historic Preservation Division, Atlanta John R. Morgan, DNR--Historic Preservation Division, Atlanta Mark Williams, University of Georgia--Department of Anthropology, Athens Economic Resources: Paul Burks, Georgia Environmental Facilities Authority, Atlanta Henry M. Huckaby, Georgia State University--College of Business Administration, Atlanta Hanna Ledford, Georgia Department of Industry, Trade and Tourism, Atlanta Paul Radford, Georgia Department of Community Affairs, Atlanta James Thompson, Georgia Environmental Facilities Authority, Atlanta Tony Tyson, Georgia Agricultural Extension Service, Statesboro Educational Resources: Greg Greer, Chattahoochee Nature Center, Atlanta Laurie Hawks, DNR--Environmental Protection Division, Atlanta Ellen Ivy, Georgia Trust for Historic Preservation, Atlanta Debi Kirkland, DNR--Commissioner's Office, Atlanta Fisheries Resources: Bobby Bell, Trout Unlimited, Rome Bob Donaghue, DNR--Pollution Prevention Assistance Division, Atlanta Jeff Durniak, DNR--Wildlife Resources Division, Gainesville Byron Freeman, University of Georgia--Institute of Ecology, Athens Cecil Jennings, University of Georgia--Warnell School of Forest Resources, Athens vi Forestry Resources: David Belcher, DNR--Wildlife Resources Division, Social Circle Bill Breiner, T & S Hardwoods, Milledgeville Frank Green, Georgia Forestry Commission, Macon Marisue Hilliard, U.S. Department of Agriculture--U.S. Forest Service, Gainesville George Martin, U.S. Department of Agriculture--U.S. Forest Service, Gainesville Geological Resources: Tom Crawford, West Georgia College--Department of Geology, Carrollton Earl Shapiro, DNR--Environmental Protection Division, Atlanta William Waggener, Georgia Institute of Technology, Atlanta Recreational Resources: Tim Banks, Rome-Floyd County Parks & Recreation Authority, Rome Chuck Gregory, DNR--Parks, Recreation and Historic Sites Division, Atlanta Alicia Soriano, DNR--Parks, Recreation and Historic Sites Division, Atlanta Scenic Resources: Jon Ambrose, DNR--Wildlife Resources Division, Social Circle Kerry Dawson, University of Georgia--School of Environmental Design, Athens Handy Johnson, DNR--Parks, Recreation and Historic Sites Division, Atlanta Christi Lambert, The Nature Conservancy of Georgia, Darien Water Quality: Glynn Groszmann, environmental consultant, Atlanta Kathy Hatcher, University of Georgia--Vinson Institute of Government, Athens Bill White, Georgia Soil and Water Conservation Commission, Athens Mork Winn, DNR--Environmental Protection Division, Atlanta Water Resources: Nap Caldwell, DNR--Environmental Protection Division, Atlanta Gail Cowie, University of Georgia--Institute of Community and Area Development, Athens Tommy Craig, environmental attorney specializing in water resources, Conyers Wade Nutter, University of Georgia--Warnell School of Forest Resources, Athens Wildlife Resources: Carroll Allen, DNR--Wildlife Resources Division, Social Circle Jon Ambrose, DNR--Wildlife Resources Division, Social Circle Brad Bergstrom, Valdosta State University--Department of Biology, Valdosta Jim Candler, Georgia Power Company, Smyrna Ron Carroll, University of Georgia--Institute of Ecology, Athens Karen Johansen, DNR--Wildlife Resources Division, Athens Terry Johnson, DNR--Wildlife Resources Division, Forsyth Jim Ozier, DNR--Wildlife Resources Division, Forsyth Geographic Information System Support: Chris Canalos, DNR--Wildlife Resources Division, Social Circle Elizabeth Cheney, DNR--Environmental Protection Division, Atlanta Susan Crow, University of Georgia--Institute of Community and Area Development, Athens Bo Lawler, University of Georgia--Warnell School of Forest Resources, Athens Hillrie M. Quin, DNR--Consultant, Atlanta Alan Sandercock, DNR--Environmental Protection Division, Atlanta Cover Page and Map 1 Design: Lenz Design and Communications, Atlanta vii viii INTRODUCTION Background Georgia has about 70,150 miles of rivers.1 Almost two-thirds of these are perennial streams, which flow all year; about one-third are intermittent streams, which are sometimes dry; and fewer than 1% are large, man-made ditches and canals. As most of them originate within the state, Georgia has a unique opportunity to determine the future of its own rivers, from their headwaters all the way downstream. Georgians are fortunate to have a good supply of clean water. Programs implemented by federal, state and local governments, industry, farmers, foresters and other individuals have greatly helped to improve water quality in our rivers over the past twenty years. Streams are no longer dominated by untreated or partially treated sewage discharge, which results in little oxygen and aquatic life. For the most part, sewage is now treated, oxygen levels have returned, and fish have followed. However, another source of pollution continues to affect Georgia's rivers. This nonpoint-source pollution consists of mud, litter, bacteria, pesticides, fertilizers, metals, oils, suds, and many other pollutants being washed into rivers by stormwater. Though this form of pollution is somewhat less dramatic than raw sewage, it poses hazards to drinking water, aquatic life, and recreational use of rivers. Georgia's rivers face still other challenges. When landowners or managers disturb the soil without effectively controlling soil movement, erosion and subsequent sedimentation may harm water quality and wildlife species which depend on clean rivers. Altering rivers and their associated wetlands and upland habitats reduces populations of many native wildlife species. Some landdisturbing activities destroy historic resources which reflect human use of rivers from earliest times. Some customary public recreational use of rivers is now being restricted. Unwise development of flood-prone areas has cost Georgia many lives and millions of dollars in property damage. Land use directly affects water quality in Georgia's rivers, and land-use planning will be necessary to manage water quality. Because there are so many small sources of nonpoint loading spread throughout the watershed, they cannot effectively be controlled by state agency permitting and enforcement, even where regulatory authority exists. Rather, control of nonpoint loading will require the cooperative efforts of many partners, including state agencies, individual landowners, agricultural and forestry interests, local county and municipal governments, and Regional Development Councils. A combination of regulatory and voluntary land management practices will be necessary to maintain the water quality of rivers at their designated use classifications, or, where they are degraded, to restore them to those levels. 1As used in this report (unless otherwise specified), the term "rivers" includes rivers, streams, creeks and other bodies of flowing water, whether perennial or intermittent, and their associated wetlands. 1 Introduction RiverCare 2000 Program Governor Zell Miller established RiverCare 2000 as a conservation program to address these challenges by improving our knowledge and management of the state's rivers. The Department of Natural Resources administers the program, with guidance from four citizens' advisory groups. Between now and the year 2000, RiverCare 2000 will consist of three related tasks: assessing important river resources throughout the state, identifying more effective management tools for river corridors2, and acquiring riverfront lands for protection, restoration, and public access. Governor Miller has named an eleven-person RiverCare 2000 Coordinating Committee to give policy-level guidance to the program. The Georgia Department of Natural Resources (DNR) has named three additional citizens' groups to make recommendations to the Coordinating Committee: C The River Assessment Team guides the evaluation of river resources and challenges, and identifies river segments which should be managed more effectively by public or private owners; C The Tools-for-Management Team evaluates ways of managing river corridors and recommends improved management methods; and C The Acquisition Criteria Team has established specific purposes for state, local and private conservation acquisition and has identified desirable kinds of lands to protect. Assessment Methodology Several southeastern states have assessed their river resources and the challenges which those resources face. Kentucky, Florida and South Carolina have completed their assessments. Tennessee's is nearly complete, and North Carolina has begun a high-priority effort. Georgia reviewed their work before determining how to structure its first broad assessment of rivers. It assembled the members of the River Assessment Team, oriented them to the task, and began evaluating its rivers in February 1996. The Team completed the assessment in April 1997. The study identifies the highest-quality segments3 of rivers in Georgia from the point of view of 15 important resources, or values: C agricultural C botanical C cultural (historic structures and archaeological resources) C economic C educational C fish resources--ecologically important C fish resources--recreational and commercial C flood plain C forestry C geological C recreational boating C scenic C water quality C water supply C wildlife 2The term "river corridors" broadly includes rivers and associated wet or dry lands. 3There is no standard length or width of a river segment for the purposes of this assessment. The locations of the resources along rivers defined the segments for each work group. 2 Introduction These are called "values" because Georgians depend on these aspects of rivers for drinking water, food, clothing, shelter, income, recreation, education, aesthetics, and spiritual renewal, among other purposes. About 60 volunteer representatives from river-resource interest groups served on the riverassessment team and in smaller technical-expert work groups. Most were educated and professionally employed in the resource area which they evaluated; some were knowledgeable amateurs. Their names and affiliations appear in the Acknowledgments section of this report. Working for the most part on their own time, these citizen advisors: C developed criteria for the assessment, C located and collected data about river segments, C analyzed the river segments, C used the criteria to rate the river segments, and C prepared the individual assessment papers which form most of this report. During the year of study and evaluation, the Team discovered that information about many rivers was scarce, and some of the available material was too old to be reliable. Funds and time did not permit Georgia to perform any new inventory or research. As a result, information coverage was uneven for most resources, both within and between watersheds. Because of time and information constraints, the Team decided to map its findings at a scale of 1:500,000 (about 7.9 miles to the inch). The base map displays only 23,185 miles of the largest rivers. It omits all intermittent streams and 47% of rivers which flow year-round. A number of work groups had information about streams which do not appear on this map. Some assigned such information to the appropriate segment of the river which does appear on the map. Other work groups added to the map a few river segments which had especially high value. Some work groups further narrowed the focus of their evaluations to stream segments lying downstream of the point at which average annual flow reaches 400 cubic feet per second4. In summary, the findings are at a very general level of detail, and the Team considers the assessment to be incomplete because some important information was unavailable. In fact, it may be more important for revealing what is not known about certain river segments than for describing what is known. This report summarizes the methods and findings of the assessment. It is an informational document, not a plan or policy statement. The report seeks to assemble existing information about important river segments in a consistent format which is easy to understand. The report summarizes information which the individual work groups assembled. The complete files of the work groups are available from the individuals listed in the following section. 4This rate of flow occurs in relatively large, perennial streams. Although the rate is somewhat arbitrary, it is practical to use because the U.S. Geological Survey has identified the places at which rivers attain this rate of flow. This rate is also consistent with current environmental legislation, since it defines river corridors for which the Department of Natural Resources must develop minimum standards and procedures for protection, pursuant to the Growth Strategies Act (Official Code of Georgia Annotated, Art. 21-2-1). 3 Introduction Information Sources For more information about the Georgia River Assessment, or the RiverCare 2000 Program in general, please contact: Mr. Harvey G. Young RiverCare 2000 Coordinator Department of Natural Resources 205 Butler Street, SE Suite 1252-E OR Atlanta, Georgia 30334 Phone: 404-657-9746 Fax: 404-656-0770 Internet e-mail: harvey_young@mail.dnr.state.ga.us Mr. Alan Hallum Chief, Water Protection Branch, EPD Department of Natural Resources 205 Butler Street, SE Suite 1058-E Atlanta, Georgia 30334 Phone: 404-656-4708 Fax: 404-656-5723 Internet e-mail: wmep.alan_hallum@mail.dnr.state.ga.us The River Assessment Report also appears on the World Wide Web at: http://www.dnr.state.ga.us/dnr/environ/gaenviro/rc2000.html 4 USING THE ASSESSMENT Individual Resource Reports This assessment report identifies many, but not all, river segments5 which are of undoubted value. The reader should use it as one of many sources of information to make decisions. The assessment especially helps identify areas needing more detailed study. Each work group differed in the information it had available, and in the degree of detail it could present in its findings. Each resource chapter describes the limitations of its information and gives specific guidance about the appropriate use of its findings. Before using this report to make decisions, the reader must understand what the assessment did, and did not, accomplish. The following paragraphs give brief, general guidance about using the individual resource chapters. However, users should review each chapter in detail before using it, to be sure they know what resources were evaluated, and what limitations are present in the data or the study process. Otherwise, they may reach erroneous conclusions using the information presented in this report. Five resource areas especially need further research: botanical, ecologically important fisheries, geological, scenic, and wildlife. Many river segments score highly in more than one resource category, some in many. However, the scores are not additive. For example, a segment with great economic potential and important fish habitat cannot fully satisfy both roles, since maximizing economic use will reduce habitat quality. Further, not all river users share the same values. A level of recreational boating that annoys one angler may not disturb another. C Agricultural resources: This assessment summarizes the best current, available knowledge about the agricultural values of 53 watersheds in Georgia. The report identifies watersheds which have high value for agricultural production, chiefly because they have existing permitted irrigation-water withdrawals. However, the reader cannot assume that other watersheds have low value. This report is not suitable for identifying high-quality agricultural tracts on specific rivers, since the information is aggregated at the watershed level. C Botanical resources: This assessment summarizes the best current, available knowledge about the condition of botanical resources in Georgia's major river basins. However, data are scarce for many segments. Though this report identifies river segments containing high-quality botanical resources, the reader cannot assume that resource quality is low in other segments. An on-site survey for rare plants and intact natural communities is the only certain way to collect information needed for site-specific decisions. C Cultural resources: This assessment includes both archaeological and historic resources. Because many cultural resources have market value, and are at risk from looting, this report does not identify the exact locations of the resources. Perhaps its major values are to reveal 5For purposes of this report, "river segment" means a river reach of indeterminate length. Standard river segments, such as fixed lengths of stream or reaches between tributaries, do not help locate or describe resources of interest. 5 Using the Assessment how intensively people have depended on rivers, from the beginning of time, and to indicate that rivers throughout Georgia have great cultural-resource value. Questions about the location and importance of specific cultural resources should be referred to the Department of Natural Resources' Historic Preservation Division, at 404-656-2840 (fax: 404-651-8739) in Atlanta. C Economic resources: This assessment considers the following sources of economic value: surface-water supply, waterborne commerce, wastewater treatment, sport fishing, electrical power generation, and agricultural irrigation. Surface-water supply contributes 95% of the total economic value identified by the assessment, and in 90% of cases it determines the rank order of the river segments. Due to limitations of data and time available for this study, and to certain assumptions made in calculating economic value, the results should be considered as preliminary rather than definitive. The aggregate economic values for the counties should be considered as relative rankings, not as absolute measures of economic value. Further, counties whose aggregate values are within 10% of one another should be regarded as having similar economic value. C Educational resources: For purposes of this assessment, educational resources are organizations, sites or programs which offer water-related educational opportunities to audiences such as primary and secondary students, college or university students, educators, policy makers and the public. C Fish resources--ecologically important: This assessment is a guide chiefly to river systems in which research has found sensitive biodiversity elements. Many river segments not ranked in this assessment are also important for biodiversity. The report identifies segments which have high ecological value, but the reader cannot assume that other watersheds have low value. Until research provides better information on more river segments, this report is best used to identify those which have known ecological importance, and to identify areas for further study. C Fish resources--recreational and commercial: This assessment summarizes the best current, available knowledge about the presence of recreational and commercial fishery resources in Georgia's major river basins. However, data are scarce for many segments, and knowledge is limited in many others. Though this report identifies river segments containing high-quality fishery resources, the reader cannot assume that resource quality is low in other segments. C Flood-plain resources: The wetlands land-cover category which this assessment uses to identify flood-plain resources probably under-represents wetlands throughout the state and also imperfectly represents the true extent of flood plains. The work group compiled this information only for broad assessment and planning purposes. It identifies some values which Georgia's river systems possess. River segments which appear in this evaluation have floodplain and wetland resources which are of high quality. However, many of these segments have higher quality than suggested in this chapter. Many smaller stream corridors which did not receive evaluation also have high-quality flood-plain and wetland resources. C Forest resources: This assessment gives a broad picture of which major river corridors have extensively forested riparian areas. The ranking of segments is relative, but segments which are close together in the ranking probably have very similar value. The study is too general to be useful for assessing the economic value of forest resources in a specific river corridor. 6 Using the Assessment C Geological resources: The assessment evaluated the following resource categories: caves, channel patterns, faults, fossil-collecting localities, geological education localities, gorges and canyons, mineral collecting localities, scientifically critical sites, springs, river terraces, and waterfalls. Constraints on data and on time for evaluation limited the work group to a cursory review of most of these categories. As a result, these overall ratings must be considered as preliminary. However, the analysis shows that many stream segments in Georgia contain very important geological resources. C Recreational boating resources: The assessment considers river segments which are suitable for recreational boating but where public access is deemed to be inadequate. It does not consider suitable segments where public access is adequate, nor does it consider recreational boating on lakes. The report generally identifies river segments which may offer new opportunities for recreational boating and may be worth evaluating in detail. It also gives a sense of the relative potential of these segments. However, it does not indicate if the river landowners will allow boating access, nor does it determine what segments are most suitable for specific types of recreational boating. C Scenic resources: The core streams for this evaluation were those mentioned in a popular two-volume canoeing guide. The work group added seven other streams that its members knew to be scenic. The streams evaluated varied from mountain creeks to coastal plain rivers, and could be considered a representative sample of some of the more attractive, navigable streams in the state. Undoubtedly, many streams with significant scenic resources exist but have not been included in this assessment. C Water-quality resources: The Board of Natural Resources designates water use classifications, such as "fishing," "recreation," and "drinking water," in the rules and regulations for water-quality control. The classification does not mean the standards assigned to that classification are met all day, every day, in any water body. The Environmental Protection Division periodically monitors water quality in the state's rivers, to determine if the standards are being met. The sampling results are summarized in the publication Water Quality in Georgia, published every two years as required by section 305(b) of the federal Clean Water Act. However, sampling shows the quality of the water only at the moment and in the place where sampling occurred, and does not indicate its quality at any other time or place. C Water-supply resources: This assessment considers river segments with existing permitted water withdrawals, and certain segments which have the capacity to meet future demand for surface-water supplies. All these segments lie north of the Fall Line, since groundwater supplies most water south of this line. The work group compiled this information only for broad assessment and planning purposes. This assessment does not identify all current or potential sources of water, nor does it state how much water individual watersheds might yield. The information chiefly helps identify some of the more important values which Georgia's rivers offer. C Wildlife resources: This assessment summarizes the best current, available knowledge about the condition of wildlife habitats in Georgia's river corridors. However, data are scarce for many segments. Though this report identifies river segments containing high-quality wildlife habitats, the reader cannot assume that habitat quality is low in other segments. An on-site survey for habitat quality and wildlife populations is the only certain way to collect information needed for site-specific decisions. 7 Using the Assessment Individual Resource Maps and Data Summaries Each resource chapter contains a map of the river segments which score as Superior, Outstanding, or Significant6. It shows where the segments are located, and how they relate to each other geographically. The map accurately portrays the quality of the segments for which current information was available. However, a river segment may have higher resource quality than the map illustrates. If the resource work group did not have relatively current information about the segment, it did not include the segment in its ratings. Using these maps, the reader can determine the general level of values which a river has. A river segment which scores as Superior in five resource categories is not necessarily "better" than a river which scores as Superior in three categories, but the former may offer more diverse opportunities to the community, and it may also have the potential for more conflicts between uses. Each chapter also contains a statistical summary which gives both the number and the percentage of miles of high-scoring segments that are located in each of the state's 14 river basins. The table allows the user to compare the resource significance of different river basins, or to compare the relative significance of various resources within a single basin. Each work group prepared a list of the river segments which were ranked in each scoring category. The locations of these segments were put into a geographic information system (GIS) database, which then generated the maps. The statistical summary was also prepared from the database. Composite Data Summary and Resource Map To make the assessment findings more useful, DNR has prepared a data summary and a map showing six composite classes of resources, as follows: C Natural rivers: segments identified as superior7 botanical, fisheries-ecology, flood-plain, forestry, scenic, water-quality, or wildlife resources. This grouping shares values which the community obtains by maintaining the river and its adjacent uplands in a generally unaltered condition. C Recreational/educational rivers: segments identified as superior cultural (archaeological resources or historic structures), geological, recreational boating, or recreational fish resources, or as outstanding water-quality resources. This grouping shares values which the community obtains through human use that makes little change to the river or its adjacent uplands. C Developed rivers: segments identified as superior agricultural, economic or water-supply resources, or as significant water-quality resources. This grouping shares values which the community can obtain only by significantly altering the river or its adjacent uplands. 6These classes are not defined by standard scores. Each work group defined the classes based on the data which were available for the assessment. Each resource chapter describes how the scores were assigned. 7For simplicity's sake, these maps include all river segments rated as "Superior," and all segments rated under water quality as "Outstanding" or "Significant." 8 Using the Assessment C Natural and recreational/educational rivers: segments identified as at least one of the natural and at least one of the recreational/educational resources. These segments may offer greater opportunities for protection and for use by the general public, because they combine several important values which are mutually compatible. C Natural and developed rivers: segments identified as at least one of the natural and at least one of the developed resources. These segments may require community involvement in priority setting, because conflicts are likely to occur between the possible uses of the segment. Protecting natural features may limit the benefits available from some developed uses; for example, maintaining drinking-water quality may restrict some activities of waterborne commerce. On the other hand, developing resources may alter or eliminate some of the natural features; for example, an impoundment may eliminate the recreational or educational value of a waterfall, a population of endangered plants, or forested lands. C Recreational/educational and developed rivers: segments identified as at least one of the recreational/educational and at least one of the developed resources. These segments may require community involvement in priority setting, because conflicts may occur between possible uses of the segment. For example, the community may view agricultural uses as being compatible with recreational boating, but some economic activities may not be viewed as compatible with sport fishing. C Natural and recreational/educational and developed rivers: segments identified as at least one of the natural and at least one of the recreational/educational and at least one of the developed resources. These segments will almost certainly require community involvement in planning priority setting, because conflicts between possible uses are very likely to exist, and there may be more than one resolution of these conflicts that the community will find acceptable. On page 11 is a statistical summary which gives, for each composite grouping listed above, the number and the percentage of miles of segments that are located in each of the 14 river basins. Using this table, the user can compare the resource significance of different river basins, or compare the relative significance of various resources within a single basin. Use by the Coordinating Committee and DNR The assessment report will help the Tools-for-Management Team decide which river challenges most urgently need to be addressed. The report's findings will guide state acquisition efforts into certain high-value river segments. They will also help DNR set priorities for more thorough inventory and research about various river-based resources. In 1992, the General Assembly enacted a law (O.C.G.A. 12-5-520) which established a river-basin management planning (RBMP) approach to watershed protection. This law designated the Chattahoochee, Flint, Coosa, and Oconee river basins as the first to be addressed. The Environmental Protection Division has begun collecting data in these four watersheds. The work products of the RBMP effort have supported the statewide river evaluation. In addition, the Department will use information about river corridors which was developed under previous programs to support decisions about the RiverCare 2000 Program's corridor-management priorities. 9 Using the Assessment DNR will use the assessment findings as it implements the RiverCare 2000 Program and other activities. It hopes the report will be useful to everyone who has a stake in river use, including landowners, governmental officials, private developers, conservationists, and outdoor recreationists. Because DNR considers these analyses and findings to be preliminary, rather than definitive, the assessment report is, first and foremost, an educational tool. The selected references which appear at the end of each chapter and again in the selected bibliography guide the user who needs more information to some of the sources used by the work teams. (Additional information used in the Geographic Information System work is referenced only in the bibliography.) This report does not mention all materials which the work groups used. A user who wishes to explore a topic more fully should contact either of the persons shown on page 4, who can connect the user with the appropriate work-group members. 10 RIVER SEGMENTS BY COMPOSITE CLASS AND RIVER BASIN RIVER BASIN Natural (lt. blue + purple + dk. blue + red) Recreational/ Educational (orange + green + purple + red) Developed (yellow + green + dk. blue + red) Composite Resource Classes Overlap of Natural with Recreational/ Educational (purple + red) Overlap of Natural with Developed (dk. blue + red) Overlap of Recreational/ Educational with Developed (green + red) Miles % Miles % Miles % Miles % Miles % Miles % Altamaha 337 1.5 260 1.1 1,054 4.5 260 1.1 334 1.4 260 1.1 Chattahoochee 166 0.7 539 2.3 1,767 7.6 38 0.2 92 0.4 324 1.4 Coosa 202 0.9 1,184 5.1 1,448 6.2 182 0.8 101 0.4 848 3.7 Flint 631 2.7 684 3.0 1,533 6.6 414 1.8 358 1.5 374 1.6 Ochlockonee 32 0.1 145 0.6 291 1.3 31 0.1 23 0.1 97 0.4 Ocmulgee 574 2.5 487 2.1 1,793 7.7 470 2.0 516 2.2 434 1.9 Oconee 471 2.0 325 1.4 552 2.4 293 1.3 256 1.1 143 0.6 Ogeechee 352 1.5 476 2.1 670 2.9 241 1.0 237 1.0 213 0.9 Saint Mary's 150 0.6 145 0.6 46 0.2 139 0.6 42 0.2 42 0.2 Satilla 336 1.4 278 1.2 964 4.2 218 0.9 278 1.2 266 1.1 Savannah 559 2.4 732 3.2 842 3.6 426 1.8 319 1.4 291 1.3 Suwannee 217 0.9 162 0.7 1,130 4.9 44 0.2 158 0.7 112 0.5 Tallapoosa 22 0.1 33 0.1 121 0.5 17 0.1 22 0.1 30 0.1 Tennessee 77 0.3 437 1.9 189 0.8 56 0.2 0 0.0 1 0.0 TOTALS 4,126 17.8 5,887 25.4 12,400 53.5 2,829 12.2 2,736 11.8 3,435 14.8 Overlap of Natural with Recreational/ Educational, and with Developed (red) Miles % 260 1.1 36 0.2 94 0.4 236 1.0 23 0.1 423 1.8 143 0.6 165 0.7 42 0.2 207 0.9 240 1.0 19 0.1 17 0.1 0 0.0 1,905 8.2 Not Rated (no color) Miles 7 905 357 694 87 683 1,564 1,062 53 333 1,592 272 104 160 7,873 % 0.0 3.9 1.5 3.0 0.4 2.9 6.7 4.6 0.2 1.4 6.9 1.2 0.4 0.7 33.8 Using the Assessment 11 Note: This table includes all segments rated as "Superior," plus water-quality segments rated as "Outstanding" or "Significant." Mileage figures are rounded to miles, percentage figures to tenths of a percent. The total mileage in this table cannot be summed to create total river mileage, since mileage in one class may also appear in one or more other classes. AGRICULTURAL RESOURCES Resources Evaluated The Agricultural Resources Work Group used both agricultural land and prime farmland in its assessment of agricultural resources. Agricultural lands in general are those used for pasture, nurseries, orchards, and the production of crops and livestock. They frequently occur along river corridors, within rich and productive flood-plain and bottomland areas. Prime farmland has the best combination of physical and chemical characteristics for producing food, feed, fiber, and oilseed crops, and is also available for these uses. It has the soil quality, growing season, and moisture supply needed to produce sustained high yields of crops economically when treated and managed according to modern farming methods, including water management. Prime farmland could currently be in crops, pasture, or forest production, but not in urban uses or beneath an impoundment, since these two uses permanently remove land from agricultural use. Resource Importance Agricultural lands are extremely valuable for food production, and they provide jobs and financial income. They have long played an important role in shaping Georgia's landscape and economy. Since James Oglethorpe settled Georgia in 1733, agriculture has been a vital component in the state's economic development and progress. While cotton served as farmers' mainstay for many years, a movement toward diversification began after the Civil War. This movement prompted many farmers, in spite of obstacles, to pursue the production of livestock, poultry, bees, and a variety of vegetable and horticultural crops. Some of these endeavors proved successful, while others, such as rice and sugar cane production, have declined through the years. Yet each of these commodities has contributed to the strength and diversity of Georgia's present agricultural structure. No matter how urbanized and industrialized Georgia becomes, agriculture will remain a vital part of the state's future progress and success. The actual acreage of cropland represents nearly 23% of Georgia's total land use. Because crops transpire large amounts of water and natural precipitation can be highly variable throughout the growing season, many farmers have come to depend on controlled irrigation to prevent fluctuating crop yields between years on Georgia's agricultural lands. Irrigation systems have become more cost-effective, and their use in Georgia has increased substantially in recent years, due to improved irrigation technology and the potential stabilizing effects on farm income. At present, Georgia has about 18,000 irrigation systems in Georgia, of which 11,000 are surface water systems. Minimum Standards for Evaluation The U.S. Geological Survey has divided Georgia's 14 major river basins into 53 watersheds. The work group defined its river segments to coincide with these watersheds, and evaluated each according to the following criteria: 12 Agricultural Resources C the percentage of land cover in cultivated earth or pasture; C the percentage of prime farmland; and C the number of surface-water irrigation permits. Constraints on the evaluation of agricultural lands include: C Land-cover data come from LANDSAT Thematic Mapper satellite imagery (bands 1-5) with a spatial resolution of 100 ft. x 100 ft. Image dates are winter 1988-1990. All of the data from the original raster imagery were assembled into 15 land-cover classes by ERDAS, Inc., Atlanta, Georgia, and the Georgia Natural Heritage Program, Wildlife Resources Division, Georgia Department of Natural Resources. The work group assumed the acreage figures to be accurate only to tens of acres, as the original land cover database was about 85% accurate. C Prime farmland data come from a U.S. Department of Agriculture listing dated May 1981. C Surface-water withdrawal permits come from a Georgia Department of Natural Resources listing dated June 1996. Assignment of Values to River Segments The work group assigned the following criteria point values to each watershed as shown: C Percentage of land cover in cultivation or pasture: The score is the actual percentage, rounded to the nearest whole number. Values ranged from 1.39% to 54.16%, or 1 to 54 points. C Percentage of prime farmland: Watersheds with over 50% prime farmland earned 20 points; those with 25% to 50% earned 15 points; and those with less than 25% prime farmland earned 10 points. C Number of surface-water irrigation permits withdrawing at least 100,000 gallons per day: The score is one point for each permit. The work group totaled point values in each of the three evaluation criteria to obtain a value for each watershed. The point totals for all watersheds were ranked from largest to smallest, and then divided into quartiles, as follows: Value Class Superior Outstanding Significant Basis for the Watershed Rating First quartile (score of 320-1542 points) Second quartile (score of 84-319 points) Third quartile (score of 44-83 points) The watersheds in the fourth quartile (score below 44 points) received no further review. Findings 1. What Is Known The work group evaluated 157 stream segments in this study and summarized its findings by the 53 watersheds. The distribution of stream segments among the three value classes was as follows: 13 Agricultural Resources Value Class Superior Outstanding Significant Number (Percentage) of Watersheds 13 watersheds (25%) 13 watersheds (25%) 13 watersheds (25%) The 14 watersheds in the lowest quartile received no further review. Watersheds located in predominantly agricultural areas of the state ranked in the highest value class (Superior). The five highest-ranked watersheds were the Alapaha (1,542 pts.), Satilla (1,268 pts.), Little (949 pts.) Withlacoochee (867 pts.), and Lower Ocmulgee (767 pts.). The five watersheds with the least agricultural activity were the Upper Little Tennessee (22 pts.), Upper Suwanee (21 pts.), St. Marys (15 pts.), Ogeechee Coastal (13 pts.) and Cumberland-St. Simons (11 pts.). The work group assigned each watershed to a value class by summing the points available for percentage of agricultural land (1-54 points), percentage of prime farmland (10, 15 or 20 points), and number of agricultural irrigation permits issued (0-1,484 points). For the 26 highest-scoring watersheds, the order of total scores is nearly the same as the order of the number of irrigation permits. (The three exceptions do not affect the value classes for those watersheds.) Using this method, a watershed rates highly for agricultural value chiefly if it has many permitted irrigation units. Agricultural use without irrigation, and the presence of prime farmland, have much less effect on the watershed's rating, until the number of irrigation permits in the watershed falls to the level at which a watershed is in the Significant value class. The following table illustrates this point: Value Class Superior Outstanding Significant Average Number of Points per Watershed % Ag. Land % Pri. Farm # Irrig. Perm. Total Score 35 19 644 698 28 18 118 164 21 14 26 61 2. What Is Not Known Figures for the percentage of land cover in cultivation or pasture date from 1988-1990. Some watersheds may have experienced significant changes from or to agricultural use since then, but more recent data are unavailable. Data on surface-water irrigation permits are about one year old. However, a permit simply authorizes the use of water to exceed 100,000 gallons per day. The work group did not know how much water the permittees actually used, or how much water was used by people who withdrew less than 100,000 gpd and therefore did not require a permit. The work group also had no information about the exact changes in water withdrawal from day to day. In general, agricultural water withdrawal is seasonal, being heaviest during dry periods in the growing season. Dividing the state into 53 watersheds for evaluation gives a very general picture of riverrelated agricultural resources. This assessment gives no detail about the agricultural value of individual river segments or their tributaries. 14 Agricultural Resources Remarks 1. Major Threats and Sources of Change to the Resource Land not committed to irreversible uses, such as urban uses or impoundments, may be available for agricultural production. Decision makers must be aware of the long-term implications of various land use options for production of food, feed, etc., and the tradeoffs involved. Actions that put high-quality farmland in irreversible uses should be initiated only if these actions are clearly in the public interest. 2. Recommendations for Improved Assessment The work group recommends that the Department of Natural Resources lead an effort to improve the evaluation of agricultural resources in river corridors, as follows: C Collect information on actual surface-water irrigation withdrawals by permit holders C Collect information to estimate surface-water irrigation withdrawals by individuals not required to have permits C Update land-cover percentages, using current satellite imagery C Update prime-farmland percentages, using current information C Use this information to re-assess watershed values Selected References GEORGIA DEPARTMENT OF NATURAL RESOURCES. 1996. State of Georgia landcover statistics by county, Wildlife Resources Division, Georgia Geological Survey Project Report #26, Atlanta. 57 p. 15 Agricultural Resources BLANK PAGE 16 Agricultural Resources RIVER SEGMENT RATING SUMMARY Agricultural Resources Basin Altamaha Chattahoochee Coosa Flint Ochlockonee Ocmulgee Oconee Ogeechee Saint Marys Satilla Savannah Suwannee Tallapoosa Tennessee Totals Superior Miles Percent 1,054 4.6 1,257 5.4 291 1.3 1,206 5.2 323 1.4 777 3.4 1,130 4.9 6,038 26.0 Value Classes Outstanding Miles Percent 1,285 5.5 1,314 55 1,302 2,326 1,046 5.7 0.2 5.6 10.0 4.5 227 1.0 233 1.0 7,788 33.6 Significant Miles Percent 1,341 5.8 1,339 5.8 45 0.2 1,590 212 217 4,744 6.9 0.9 0.9 20.5 Note: Mileage is rounded to the nearest mile, and percentage to the nearest tenth of a percent. A blank cell indicates that no segment of the river met the criteria for rating. A mileage cell containing 0 indicates that less than 0.5 miles of river qualified for the level. A mileage cell containing a number larger than 0, whose corresponding percentage cell contains 0.0, indicates that the mileage which qualified for the level was less than 0.05% of total miles rated in this class. 17 Value Class Superior Outstanding Significant Base Map Features Major Rivers Interstate Highways County Lines Value Class Superior Outstanding Significant Base Map Features Major Rivers Interstate Highways County Lines BOTANICAL RESOURCES Resources Evaluated The Botanical Resources Work Group considered three types of botanical resources: C rare plants, including only those native plant species officially designated as threatened or endangered, or considered as special-concern plants of demonstrated scarcity in Georgia; C natural communities having one or more intact natural habitats which are significant at the state or regional (that is, major-watershed) level; and C wildflower-rich areas, which have a seasonal display of showy wildflowers, some of which may be rare. Resource Importance Native plant species are a part of the web of life and are necessary for human survival. Their presence enriches humans aesthetically and spiritually. Populations of some species act as a barometer of environmental health. Various species provide food and may be a source of pharmaceutical chemicals. Botanical resources are also important for environmental education and enjoyment of the out-ofdoors. Wildflower displays have additional recreational value and are enjoyable by everyone, not just scientists and educators. Furthermore, intact natural areas, upon which our botanical resources depend, provide watershed protection, thus enhancing water quality, scenic beauty, wildlife diversity and the quality of greenway corridors and other river experiences. About half of Georgia's rare-plant species depend upon habitats formed by or found along major rivers and streams. One valuable function of river corridors is to provide habitat for rare species. For example, 10 of the 24 federally listed threatened-and-endangered plants documented from Georgia occur along rivers and streams--in shoals, on bluffs created by river flows, in gorges of the Blue Ridge, in flood plains, in crevices of bedrock in the actual stream bed, and on bouldery gravel bars maintained by natural flooding events. Minimum Standards for Evaluation (1) A river segment must contain at least one of the above three botanical resources. Significant natural communities do not always harbor rare plants, but the diversity of native species, and the size and natural quality of the site, are important criteria for this assessment. (2) A river segment must be at a large enough scale to be found on a 1:100,000-scale topographic map. The work group evaluated some small streams, but it excluded springheads, pitcher-plant bog seeps, isolated swamps, sag ponds, vernal pools and other sensitive wetlands not directly associated with larger streams and rivers. Significant intermittent streams were 18 Botanical Resources considered if they appeared on 1:100,000-scale maps. Well-documented botanical resources now found along impoundments qualified, but emphasis was on free-flowing stream habitats. (3) An identified river segment included anything river-related in the broadest sense, such as bluffs, dunes and rock outcrops along watercourses, flood plains and swamps. To review rare-plant data, the work group defined corridors along the major streams and rivers. In north Georgia, they were limited to one-quarter mile on each side of the waterway; in the piedmont, to half a mile on each side; and in the coastal plain, to one mile on each side. The resulting watershed maps provided point data for locations of rare species. The work group evaluated the segments using all available knowledge of the plant occurrences, then generalized the rare-plant locations to river segments, to protect them from vandalism or commercial exploitation. Assignment of Values to River Segments The work group evaluated each stream and river segment for the presence of rare plants, significant natural communities and wildflower displays. It assigned segments to the appropriate value class, depending on which of the following criteria they met: Value Class Superior Basis for the Segment Rating The segment contains at least one federally listed plant, two state-protected plants, or five special-concern plants; at least one significant natural community; high diversity (many native species); and high richness (many individuals of many plant species). Outstanding The segment contains at least one listed species, or three special-concern plants; at least one high-quality significant natural community (intact and recoverable with little disturbance, some logging, or some grazing); high diversity; and moderate richness. Significant The segment contains at least one special-concern plant; at least one moderate-quality significant natural community (considerable disturbance, but intact and recoverable); only moderate diversity; and low to moderate richness. Findings 1. What Is Known In all, 161 river segments qualified for one of the three value classes. The work group rated them as follows: 19