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4.5.16 Savannah River Basin 4.5.16.1 River Basin Description The headwaters of the Savannah River Basin begin along the eastern slopes of the Blue Ridge Mountains and flow south through Georgia and South Carolina to empty into the Atlantic Ocean. Only 2% of the total Savannah River Basin is within North Carolina. The basin encompasses 172 square miles, making it the smallest of the state’s river basins. The North Carolina portion has approximately 176 miles of streams and 1,366 reservoir acres. Streams in the North Carolina portion of the basin are part of the Tugaloo River and Seneca River subbasins; however, both of these named rivers begin outside the state. Major tributaries of the Tugaloo in North Carolina are the Overflow and Big creeks, and the Chattooga River. Major tributaries of the Seneca River in North Carolina include the Toxaway, Horsepasture, Thompson, and Whitewater rivers. Land use in the basin is 91% forested, 1% agricultural, 7% urban or developed, and less than 1% grassland and wetland (MRLC 2011; Jin et al. 2013). A significant portion of the basin is publicly owned land, primarily Nantahala National Forest (189,060 acres), Pisgah National Forest (107,111 acres), NCWRC game lands (nearly 3,000 acres), and Gorges State Park (7,640 acres). The basin encompasses all or part of four counties (Clay, Jackson, Macon, and Transylvania) and has one sizable municipality (Highlands). Figure 4.5.16.1 depicts the location of the basin. DRAFT, 4-121 Figure 4.5.16.1 Location of the Savannah River Basin. 4.5.16.2 Aquatic Resource Conditions Water quality is generally good for areas where data are available; however, there are problems in parts of the basin (described below), and the lack of data for nearly half the basin provides an unclear assessment of overall water quality. There are more than 320 miles of freshwater streams in the basin that have been classified by NCDWR for best uses (NCDWQ 2012g, 2015d,h). Water quality in the Savannah River Basin is excellent in major streams and most small headwater streams. There are 211 miles and 619 acres of NCDWR designated Trout waters (Tr) in the basin. Most of the Tugaloo River tributaries in North Carolina and four miles of the Horsepasture River are designated Outstanding Resource Waters (ORW), and portions of Bearwallow Creek and Whitewater River are designated High-Quality Waters (HQW). The requirements for classification as ORW are more stringent than those for HQW and in some circumstances, the unique characteristics of the resources require that a specialized management strategy be developed (NCDWQ 2015d). DRAFT, 4-122 Table 4.5.16.1 provides information on water quality classifications and use-support ratings in the basin. Table 4.5.16.1 Water quality classifications and use ratings in the Savannah River Basin. Classifications Total Basin Waters Classified Waters HQW ORW Use Ratings Total Monitored Supporting Impaired Not Rated No Data Freshwater Miles 323 260 21 41 Freshwater Miles 195 52 1 3 139 Percent (Basin Waters) 81 7 13 Percent (Monitored Waters) 27 <1 <1 71 Freshwater Acres 875 638 0 24 Freshwater Acres 691 0 0 0 691 Percent (Basin Waters) 73 0 3 Percent (Monitored Waters) 0 0 0 100 There are several small reservoirs, including Cashiers Reservoir, Fairfield Reservoir, and Toxaway Reservoir, and many smaller ponds associated with golf courses and second home developments in the Cashiers/Highlands area. 4.5.16.3 Aquatic Species There are nine SGCN in the basin: two crayfish species and seven freshwater fish species. Appendix G provides a list of SGCN and other priority species for which there are knowledge gaps or management concerns. Appendix H identifies SGCN associated with aquatic communities found in this river basin.Table 4.5.16.2 identifies the priority species found in the Savannah River Basin. DRAFT, 4-123 Table 4.5.16.2 SGCN in the Savannah River Basin. Taxa Group CRAYFISH FISH Scientific Name Cambarus chaugaensis Cambarus reburrus Ameiurus brunneus Ameiurus platycephalus Etheostoma inscriptum Hybopsis rubifrons Notropis lutipinnis Percina nigrofasciata Salvelinus fontinalis Common Name Chauga Crayfish French Broad River Crayfish Snail Bullhead Flat Bullhead Turquoise Darter Rosyface Chub Yellowfin Shiner Blackbanded Darter Brook Trout (Native) Federal/State Listing Status* - /SC - /T - /T - /SC - /T *See Section 4.5.3. 4.5.16.4 Threats Affecting Aquatic Species While much of the North Carolina portion of the basin is in national forest and state-owned lands, development is increasing on private lands. Nonpoint source problems (primarily erosion and sedimentation) from land clearing, removal of riparian vegetation, and rural roads are potential problems. Nutrient enrichment may also be a problem (NCDWQ 2012g). According to an NCDENR dam inventory (NCDEMLR 2014), there are 49 impoundments in the basin. Most are small privately owned lakes used for recreation, and these small impoundments fragment headwater habitats, contribute to temperature pollution, and can be a source of nonnative introductions. All of the major tributaries in North Carolina are upstream from major impoundments in Georgia and South Carolina that isolate them from the rest of the basin. Short reaches of the Horsepasture and Toxoway rivers are impounded just inside the North Carolina border (Lake Jocassee, Duke Energy). Little is known of the extent to which nonnative aquatic species have become established in the Savannah River Basin in North Carolina. Nonnative vegetation can also negatively impact native aquatic animal communities. This includes both aquatic and riparian plant species and nonnative plant pathogens that can alter riparian vegetation and affect aquatic habitats (e.g., Hemlock Wooly Adelgid). 4.5.16.5 Recommendations Conservation priorities that apply statewide to all river basins are presented in Section 4.5.3.3. Priorities identified in the Savannah River Basin are shown in Figure 4.5.16.2 and are included in Appendix J. DRAFT, 4-124 Figure 4.5.16.2 Location of priority HUC12 watersheds in the Savannah River Basin. Basin Specific Recommendations Distributional Surveys. General surveys are still needed to complete primary distributional status for SGCN and other priority species (see Table 4.5.16.2). Snails – complete primary distribution inventories; determine potential habitats and distribution surveys for hydrobiids. Determine distribution of nonnative species. Monitoring. Long-term monitoring is critical to assessing species and ecosystem health over time and gauging the resilience of organisms to continued impacts to state waters. Studies should include identification of population trends, as well as assessment of impacts from conservation or development activities. These efforts will inform species and habitat management decisions. Long-term monitoring sites need to be identified and monitoring DRAFT, 4-125 protocols developed for all priority species. Monitoring plans should be coordinated with other existing monitoring programs where feasible. Continue periodic monitoring of priority areas and species. Research. Research topics that facilitate appropriate conservation actions include habitat use and preferences, reproductive behavior, fecundity, population dynamics and genetics, feeding, competition, and food web dynamics. Increased understanding of life histories and status helps determine the vulnerability of priority species to further imperilment, in addition to identifying possibilities for improved management and conservation. All studies should provide recommendations for mitigation and restoration. Formal descriptions for known or putative undescribed species and investigations aimed at resolving taxonomic status are needed. Resolve taxonomic problems with crayfishes. Investigate impacts of fragmentation on priority species. Management Practices. Management practices that reduce impacts and work synergistically with other conservation actions are needed to enhance the resilience of natural resources. Particular needs include preserving biodiversity, protecting native populations and their habitats, and improving degraded habitats. In addition, education about, and regulation and prevention of the introduction and spread of exotic or invasive species are vital. Support conservation and restoration of streams and riparian zones in priority areas. Incorporate management goals for aquatic community conservation and enhancement planning for Gorges State Park and Toxaway Game Lands. Prioritize education and other measures to prevent the introduction or spread of invasive nonnative species, particularly crayfishes. Conservation Programs and Partnerships. Conservation programs, incentives, and partnerships should be utilized to the fullest extent in order to preserve high-quality resources and protect important natural communities. Protective measures that utilize existing regulatory frameworks to protect habitats and species should be incorporated where applicable. Land conservation or preservation can serve numerous purposes in the face of anticipated climate change, but above all, it promotes ecosystem resilience. Support the Watershed Restoration Plan (WRP) developed by NCDMS for the Savannah River Basin (NCWRP 2001d). Cooperate with NC Division of Parks and Recreation (NCDPR), the US Forest Service (USFS), and NCWRC, who manage much of the basin in North Carolina. DRAFT, 4-126