Bathymetric Maps and Water-Quality Profiles of Table Rock and North Saluda Reservoirs, Greenville County, South Carolina: U.S

U.S. Department of the Interior Scientific Investigations Map 3289 U.S. Geological Survey Prepared in cooperation with Greenville Water Plate 1 of 2

Abstract Description of the Study Area 1,252 Table 3. Near-surface and near-bottom water-quality data collected at Table Rock Reservoir, Greenville County, 1,250 South Carolina, May 14–15, 2013. The Table Rock Reservoir is located in the foothills of the Blue Ridge Mountains in Greenville County, South Carolina (fig. 1) and was Lakes and reservoirs are the water-supply source for many communities. As such, water-resource managers that oversee these water supplies 1,248 Water-quality Near-surface Near-bottom Unit require monitoring of the quantity and quality of the resource. Monitoring information can be used to assess the basic conditions within the created in 1930 by the impoundment of the South Saluda River. Both the reservoir and the surrounding watershed are owned by Greenville Water, GVD 29) 1,246 constituent measurement measurement N (

making it a well-protected source of drinking water. The watershed area, measured using a 10-meter (m) digital elevation model (DEM) (Gesch

reservoir and to establish a reliable estimate of storage capacity. In May 2013, a global navigation satellite system receiver and fathometer were t 2 1,244 Table Rock Reservoir and others, 2002; Gesch, 2007) with a geographic information system (GIS), is 9,737 acres (15.2 square miles (mi )). Table Rock Reservoir e used to collect bathymetric data, and an autonomous underwater vehicle was used to collect water-quality and bathymetric data at Table Rock e f 1,242 reaches full pool at an elevation of 1,250 feet (ft) relative to the National Geodetic Vertical Datum of 1929 (NGVD 29) (K.C. Price, Greenville

Reservoir in Greenville County, South Carolina. These bathymetric data were used to create a bathymetric contour map and stage-area and stage- i n Water temperature Degrees Celsius 17.8 8.2 1,240 Water, written commun., 2013). The surface area of the reservoir at full pool is 476 acres and includes 8.6 miles of shoreline. , volume relation tables for the reservoir. Additionally, statistical summaries of the water-quality data were used to provide a general description of n 1,238

i o pH Standard units 6.7 6.6 water-quality conditions in the reservoir. t a 1,236 v

l e 1,234 Specific conductance Microsiemens per centimeter at 25 degrees Celsius 14 15 Methods E 1,232 Introduction 850 900 950 1,000 1,050 1,100 1,150 1,200 Dissolved-oxygen concentration Milligrams per liter 9.5 9.4 The YSI EcomapperTM autonomous underwater vehicle (AUV) was used, where possible, to collect bathymetric and water-quality data Volume, in million cubic feet Greenville Water provides drinking water to more than 450,000 residents in the upstate region of South Carolina (Greenville Water, in the reservoir. The AUV can cost-effectively collect dense data by surveying large areas with minimal time compared to traditional manned boat surveys. Using the AUV, spatially dense Doppler Velocity Log (DVL) data were collected in the open-water and unobstructed areas of the Figure 3. Stage-volume curve at Table Rock Reservoir, Greenville County, 2011). The water authority obtains its drinking water from three surface-water sources: Table Rock Reservoir, North Saluda (also known as South Carolina, May 2013. Acknowledgments Poinsett) Reservoir, and Lake Keowee (fig. 1). Accurate storage capacity and water-quality data are vital for management and planning of the reservoir. On the basis of initial site reconnaissance and using the AUV’s VectorMap planning software, a data-collection plan was established drinking-water supply. Therefore, detailed surveys of bathymetry and water quality for the Table Rock Reservoir were conducted to determine using selectable settings such as depth, speed, location, and sonar resolution. Georeferenced aerial imagery of the water body was loaded into The authors would like to recognize the contributions of Greenville Water for providing boats and staff to assist in data collection. the stage (water-level)-volume relations and water-quality condition of the reservoir. The U.S. Geological Survey (USGS), in cooperation with VectorMap as background data for programming the surveys and establishing numbered waypoints, which are points placed by the user to Greenville Water, conducted bathymetric, water-quality, and imaging surveys of Table Rock Reservoir. The resulting datasets were used to indicate the route for the AUV to travel. For optimal efficiency of data collection and accuracy of the datasets, a transect spacing of approximately Water-Quality Conditions produce a digital bathymetric map of the reservoir and to describe the basic water-quality conditions within the reservoir at the time of data 100 ft or 1 percent of the longitudinal length of the lake was used (Wilson and Richards, 2006). The AUV uses a Wide Area Augmentation Spatial variability of water-quality conditions were assessed in Table Rock Reservoir for May 14–15, 2013. Subsequent data were collected collection. System (WAAS) capable global positioning system (GPS) to navigate on the water surface and a DVL instrument for underwater navigation, Selected References which includes vertical beams for altitude and depth measurement. As a failsafe, the AUV can use an internal compass in the event that a problem on June 12, 2013, in order to add more depth data in targeted areas of the reservoir. As mentioned previously, water-quality conditions were occurs with the DVL. Vertical accuracy of the DVL at depths of 0 to 200 ft is ±0.4 ft (YSI, Incorporated, 2011). relatively uniform and demonstrated minimal spatial variability. Environmental Systems Research Institute, 2013, ArcGIS Help 10.1: Redlands, Calif., Environmental Systems Research Institute, accessed NORTH CAROLINA NORTH CAROLINA In shallow areas (generally less than 3 ft), areas containing debris, or any area otherwise difficult for theAUV to maneuver, the bathymetric During the 2-day, data-collection period in May, water-quality data were collected near the surface at depths of 2 to 6 ft. The water December 10, 2013, at http://resources.arcgis.com/en/help/main/10.1/index.html#//00qn0000001p000000. data were collected with digital echo sounding equipment attached to a manned boat. The data were collected by interfacing a 220-channel global temperature ranged from 17.3 to 21.1 degrees Celsius (oC) (table 2), and pH ranged from 5.4 to 6.3. Specific conductance ranged from 13 to Area shown navigation satellite system (GNSS) receiver and data logger to a dual-frequency fathometer and used methods described in Nagle and others 14 microsiemens per centimeter (µS/cm) at 25 degrees Celsius, and dissolved-oxygen concentrations ranged from 9.4 to 9.7 milligrams per liter Gesch, D.B., 2007, The national elevation dataset, in Maune, D., ed., Digital elevation model technologies and applications—The DEM users Lake Keowee North Saluda (2009). Horizontal accuracy of both GPS types is typically less than 3 ft. The echo sounding equipment also was used as a quality-control check (mg/L). manual (2d ed.): Bethesda, Md., American Society for Photogrammetry and Remote Sensing, p. 99–118. SOUTH CAROLINA Reservoir 176 on selected AUV transects. The time measurement accuracy of echo sounding equipment typically is rated by manufacturers at ±0.1 ft plus 0.1 to In order to determine vertical changes in the water column, a hand-held multiparameter sonde was used periodically to collect near-surface and near-bottom water-quality data. In Table Rock Reservoir, near-surface and near-bottom measurements of water temperature Gesch, Dean, Oimoen, Michael, Greenlee, Susan, Nelson, Charles, Steuck, Michael, and Tyler, Dean, 2002, The national elevation dataset: 25 0.5 percent of the depth (U.S. Army Corps of Engineers, 2002). To assess potential outliers and erroneous depth data, all data were post-processed (17.8 and 8.2 oC, respectively) demonstrated a temperature change with depth, indicating some degree of thermal stratification (table 3). A Photogrammetric Engineering and Remote Sensing, v. 68, no. 1, p. 5–11. River and imported into a three-dimensional program called ArcScene. Data that were determined to be erroneous were removed from further process- GEORGIA ing and analysis. Using a GIS, the data then were used to create a triangulated irregular network (TIN), which digitally represents a surface different pattern, however, was identified for pH, specific conductance, and dissolved-oxygen concentrations in the reservoir, which had fairly Greenville Water, 2011, 2011 Water quality report, 4 p., accessed December 10, 2013, at http://www.greenvillewater.com/wp-content/ Blue Ridge (Environmental Systems Research Institute, 2013). Using methods described by Johnson and others (2008), the TIN was used to produce contour constant measurements at both near-surface and near-bottom depths (table 3). uploads/2013/02/waterquality.pdf. Piedmont maps at 10-ft intervals and stage-volume relations. All GIS processing was accomplished by using Environmental Systems Research Institute 276 (Esri) GIS software, including ArcScene, ArcMap, and 3-D Analyst extension (Environmental Systems Research Institute, 2013). Johnson, M.R., Andersen, M.J., and Sebree, S.K., 2008, Hydrographic surveys for six water bodies in eastern Nebraska, 2005–07: Water-quality data were collected simultaneously with the bathymetric data by using a bulkhead-mounted multiparameter sonde that U.S. Geological Survey Scientific Investigations Report 2008–5048, 5 p. Table Rock South

Reservoir Saluda is part of the AUV. The water-quality data were used to assess the spatial variability of water temperature, pH, specific conductance, and Table 2. Statistical summary of water-quality conditions at Table Rock Reservoir, Greenville County, South Carolina, May 14–15, 2013. dissolved-oxygen concentrations. During the period of study, water-quality conditions in the reservoir were relatively uniform with minimal Nagle and others, 2009, Bathymetry of lake William C. Bowen and Municipal Reservoir #1, Spartanburg County, South Carolina, 2008: GREENVILLE variability; therefore, no maps of the water-quality conditions were produced. Statistical summaries of the water-quality data are provided for the [Water-quality data were collected at a depth of 2 to 6 feet] U.S. Geological Survey Scientific Investigations Map 2009–3076, 1 sheet. Saluda COUNTY

River reservoir. In addition, near-surface and near-bottom measurements of water-quality conditions were made periodically and assessed to determine Water-quality constituent Unit Minimum Maximum Mean Median North U.S. Army Corps of Engineers, 2002, Engineering and design—Hydrographic surveying, Publication No. EM 1110-2-1003, chap. 9, 3 p., SOUTH CAROLINA if changes in water quality occurred vertically in the water column. These water-quality data were collected using a hand-held multiparameter Table Rock Reservoir accessed December 10, 2013, at http://140.194.76.129/publications/eng-manuals/EM_1110-2-1003_pfl/toc.htm. sonde from a manned boat. All water-quality sensors were calibrated prior to and after the deployment according to procedures outlined by YSI and the USGS National Field Manual (YSI, Incorporated, 2011; Wilde, variously dated; respectively). Water temperature Degrees Celsius 17.3 21.1 18.1 18.0 U.S. Geological Survey, 2007, Facing tomorrow’s challenges—U.S. Geological Survey science in the decade 2007–2017: U.S. Geological Survey Circular 1309, 70 p. 29 pH Standard units 5.4 6.3 5.8 5.8 178 Wilde, F.D., ed., variously dated, Field measurements: U.S. Geological Survey Techniques of Water-Resources Investigations, book 9, chap. A6, PICKENS Bathymetry and Storage Volumes Specific conductance Microsiemens per centimeter at 25 degrees Celsius 13 14 14 14 with sec. 6.0–6.8, accessed December 10, 2013, at http://water.usgs.gov/owq/FieldManual/Chapter6/Ch6_contents.html. COUNTY 25 Saluda Wilson, G.L., and Richards, J.M., 2006, Procedural documentation and accuracy assessment of bathymetric maps and area/capacity tables for The maximum depth recorded in Table Rock Reservoir was 123 ft (fig. 2). On the basis of side-scan sonar data, there are many areas in the Dissolved-oxygen concentration Milligrams per liter 9.4 9.7 9.5 9.5 reservoir in which the relic stream channel is clearly visible. Also, no obvious areas of sediment buildup were detected. The reservoir is consid- small reservoirs: U.S. Geological Survey Scientific Investigations Report 2006–5208, 14 p.

Greenville SPARTANBURG ered to be at full pool when the surface elevation reaches 1,250 ft. Using the 3-D Analyst extension within ArcMap, the volume of the reservoir COUNTY 6 3 YSI, Incorporated, 2011, 6-Series multiparameter water quality sondes user manual: YSI, Incorporated, accessed December 10, 2013, at at full pool was determined to be 1,180 x 10 cubic feet (ft ) (table 1; fig. 3). During the data-collection period, the highest recorded surface http://www.ysi.com/media/pdfs/069300-YSI-6-Series-Manual-RevH.pdf. elevation was 1,250.2 ft. 123

River 276 N Table 1. Stage-area and stage-volume relations for selected elevations at Table Rock Reservoir, Greenville County, South Carolina, May 2013. ANDERSON 82°40'30" COUNTY [NGVD 29, National Geodetic Vertical Datum of 1929]

ESRI® Data & Maps, 2010 0 2 4 6 8 MILES Elevation Volume Surface area (acres) North American Datum of 1983 (feet, NGVD 29) (cubic feet x 106) Universal Transverse Mercator projection, zone 17 0 2 4 6 8 KILOMETERS 1,250.2 478 1,184 Figure 1. Location of Table Rock and North Saluda Reservoirs and Lake Keowee, Greenville County, South Carolina. a1,250 476 1,180 1,248 468 1,138 Purpose and Scope 1,246 460 1,098 1,244 451 1,058 The purpose of this report is to provide bathymetric, stage-volume, and water-quality data that can be used by water-resource managers to effectively plan and manage the resources available from the reservoir. Bathymetric, side-scan sonar, and water-quality data were collected at Table Rock Reservoir 1,242 443 1,019 from May 14 to June 12, 2013. The bathymetric data were used to determine stage-volume relations, which can be used to assist water authorities in 1,240 432 981 water-use planning. These relations are especially important during periods of high water usage or drought. Side-scan sonar data of the lake bed also 1,250 1,238 423 944 82°41' were collected and used to verify and aid in the development of the bathymetric map. In addition, water temperature, pH, specific conductance, and 1,236 415 907 dissolved-oxygen concentrations data were collected to provide a synoptic description of water-quality conditions in the reservoir. This investigation of bathymetry and water-quality conditions in drinking-water reservoirs in South Carolina supports two of the six USGS strategic 1,234 407 872 science directions (U.S. Geological Survey, 2007). The first strategy, Understanding Ecosystems and Predicting Ecosystem Change, is designed to study aFull-pool elevation. and monitor ecosystem change as well as interpret the findings and predictions for policymakers (U.S. Geological Survey, 2007). The second strategy is the 1,200 Water Census of the United States, which informs the public and decision makers with, among other things, the status and changes of water resources and forecasting possible outcomes for water availability, water quality, and ecosystems caused by changing environments (U.S. Geological Survey, 2007). Boat dock

35°4' 35°4' 1,200

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1,200 TABLE ROCK DAM 1,200

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0 0.05 0.1 0.2 0.3 0.4 0.5 MILE 141/2° 0 0.05 0.1 0.2 0.3 0.4 0.5 KILOMETER EXPLANATION Depth, in feet 0 SCALE 1:4,000 1,200 North

Magnetic True North True Lambert Conformal Conic projection Approximate mean North American Datum of 1983 declination, 2011 150 35°3'30" 35°3'30" For additional information, please contact the Director, South Carolina Water Science Center, email: [email protected], or visit http://sc.water.usgs.gov/. 1,200 Bathymetric contour–Line of equal lake-bottom elevation, in feet above National Geodetic Vertical Datum of 1929. Prepared by the Science Publishing Network, Raleigh Publishing Service Center Intervals are 10 feet

Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.

If printed, dimensional calibration may vary between electronic plotters and between X and Y directions on the same plotter, and paper may change size due to atmospheric conditions; therefore, scale and proportions may not be true on plots of this map. Figure 2. Bathymetric map of Table Rock Reservoir, Greenville County, South Carolina, May 2013. Suggested citation: Clark, J.M., Journey, C.A., Nagle, D.D., and Lanier, T.H., 2014, Bathymetric maps and water-quality profiles of Table Rock and North Saluda Reservoirs, Greenville County, South Carolina: U.S. Geological Survey Scientific Investigations Map 3289, 2 plates, http://dx.doi.org/10.3133/sim3289.

82°41' ISSN 2329-132X (online)

Bathymetric Maps and Water-Quality Profiles of Table Rock and North Saluda Reservoirs, Greenville County, South Carolina By Jimmy M. Clark, Celeste A. Journey, Douglas D. Nagle, and Timothy H. Lanier 2014 U.S. Department of the Interior Scientific Investigations Map 3289 U.S. Geological Survey Prepared in cooperation with Greenville Water Plate 2 of 2

Abstract Purpose and Scope Table 1. Stage-area and stage-volume relations for selected elevations at Table 2. Statistical summary of water-quality conditions at North Saluda Reservoir, Greenville County, South Carolina, North Saluda Reservoir, Greenville County, South Carolina, April 2013. April 15–18, 2013. The purpose of this report is to provide bathymetric, stage-volume, and water-quality data that can be used by water-resource managers Lakes and reservoirs are the water-supply source for many communities. As such, water-resource managers that oversee these water [NGVD 29, National Geodetic Vertical Datum of 1929] [Water-quality data were collected at a depth of 2 to 6 feet] to effectively plan and manage the resources available from the reservoir. Bathymetric, side-scan sonar, and water-quality data were collected supplies require monitoring of the quantity and quality of the resource. Monitoring information can be used to assess the basic conditions within Elevation Volume Water-quality at North Saluda Reservoir from April 15 to June 12, 2013. The bathymetric data were used to determine stage-volume relations, which can be Surface area (acres) Unit Minimum Maximum Mean Median the reservoir and to establish a reliable estimate of storage capacity. In April and May 2013, a global navigation satellite system receiver and (feet, NGVD 29) (cubic feet x 106) constituent fathometer were used to collect bathymetric data, and an autonomous underwater vehicle was used to collect water-quality and bathymetric data used to assist water authorities in water-use planning. These relations are especially important during periods of high water usage or drought. 1,230.3 1,052 3,195 North Saluda Reservoir at North Saluda Reservoir in Greenville County, South Carolina. These bathymetric data were used to create a bathymetric contour map and Side-scan sonar data of the lake bed also were collected and used to verify and aid in the development of the bathymetric map. In addition, a stage-area and stage-volume relation tables for the reservoir. Additionally, statistical summaries of the water-quality data were used to provide a water temperature, pH, specific conductance, and dissolved-oxygen concentrations data were collected to provide a synoptic description of 1,230 1,049 3,181 Water temperature Degrees Celsius 14.2 18.1 15.0 14.9 water-quality conditions in the reservoir. general description of water-quality conditions in the reservoir. 1,228 1,033 3,091 pH Standard units 5.6 6.8 6.3 6.3 This investigation of bathymetry and water-quality conditions in drinking-water reservoirs in South Carolina supports two of the six USGS strategic science directions (U.S. Geological Survey, 2007). The first strategy, Understanding Ecosystems and Predicting Ecosystem Change, 1,226 1,018 3,001 Specific conductance Microsiemens per centimeter at 25 degrees Celsius 23 24 23.8 24 is designed to study and monitor ecosystem change as well as interpret the findings and predictions for policymakers (U.S. Geological Survey, 1,224 1,003 2,913 Dissolved-oxygen concentration Milligrams per liter 10.2 10.7 10.4 10.4 Introduction 2007). The second strategy is the Water Census of the United States, which informs the public and decision makers with, among other things, the 1,222 988 2,826 status and changes of water resources and forecasting possible outcomes for water availability, water quality, and ecosystems caused by changing 1,220 970 2,741 Greenville Water provides drinking water to more than 450,000 residents in the upstate region of South Carolina (Greenville Water, environments (U.S. Geological Survey, 2007). 2011). The water authority obtains its drinking water from three surface-water sources: Table Rock Reservoir, North Saluda (also known as 1,218 949 2,657 Poinsett) Reservoir, and Lake Keowee (fig. 1). Accurate storage capacity and water-quality data are vital for management and planning of the 1,216 931 2,575 Table 3. Near-surface and near-bottom water-quality data collected at North Saluda Reservoir, Greenville County, drinking-water supply. Therefore, detailed surveys of bathymetry and water-quality for the North Saluda Reservoir were conducted to determine Description of the Study Area 1,214 913 2,495 South Carolina, April 15–18, 2013. the stage (water-level)-volume relations and water-quality condition of the reservoir. The U.S. Geological Survey (USGS), in cooperation with a The North Saluda Reservoir, which also is known as the Poinsett Reservoir, is located in the foothills of the Blue Ridge Mountains in Full-pool elevation. Greenville Water, conducted bathymetric, water-quality, and imaging surveys of North Saluda Reservoir. The resulting datasets were used to Water-quality Near-surface Near-bottom Greenville County, South Carolina (fig. 1). The reservoir was created by the impoundment of the North Saluda River and was put into operation Unit produce a digital bathymetric map of the reservoir and to describe the basic water-quality conditions within the reservoir at the time of data constituent measurement measurement in 1961. Both the reservoir and the surrounding watershed are owned by Greenville Water, making it a well-protected source of drinking water. collection. North Saluda Reservoir The watershed area, measured using a 10-meter (m) digital elevation model (DEM) (Gresch and others, 2002; Gesch, 2007) with a geographic Water temperature Degrees Celsius 16.6 8.3 information system (GIS), is 16,122 acres (25.2 square miles (mi2)). North Saluda Reservoir reaches full pool at an elevation of 1,230 feet (ft) 1,232 relative to the National Geodetic Vertical Datum of 1929 (NGVD 29) (K.C. Price, Greenville Water, written commun., 2013). The surface area of 1,230 pH Standard units 6.9 6.8 the reservoir at full pool is 1,049 acres and includes 17.9 miles of shoreline. 1,228 Specific conductance Microsiemens per centimeter at 25 degrees Celsius 23 24 NORTH CAROLINA NORTH CAROLINA GVD 29) 1,226 Dissolved-oxygen concentration Milligrams per liter 9.8 9.7 N (

t 1,224 Area shown e

e 1,222 f Lake Methods

Keowee North Saluda i n 1,220

SOUTH CAROLINA Reservoir 176 , TM n 1,218

The YSI Ecomapper autonomous underwater vehicle (AUV) was used, where possible, to collect bathymetric and water-quality data i o t

25 a 1,216

in the reservoir. The AUV can cost-effectively collect dense data by surveying large areas with minimal time compared to traditional manned v

River l e 1,214

GEORGIA boat surveys. Using the AUV, spatially dense Doppler Velocity Log (DVL) data were collected in the open-water and unobstructed areas of the E reservoir. On the basis of initial site reconnaissance and using the AUV’s VectorMap planning software, a data-collection plan was established 1,212 Blue Ridge 2,400 2,600 2,800 3,000 3,200 3,400 Piedmont using selectable settings such as depth, speed, location, and sonar resolution. Georeferenced aerial imagery of the water body was loaded into 276 VectorMap as background data for programming the surveys and establishing numbered waypoints, which are points placed by the user to Volume, in million cubic feet indicate the route for the AUV to travel. For optimal efficiency of data collection and accuracy of the datasets, a transect spacing of approximately Table Rock Figure 3. Stage-volume curve at North Saluda Reservoir, Greenville County, South 100 ft or 1 percent of the longitudinal length of the lake was used (Wilson and Richards, 2006). The AUV uses a Wide Area Augmentation

Reservoir Saluda System (WAAS) capable global positioning system (GPS) to navigate on the water surface and a DVL instrument for underwater navigation, South Carolina, April 2013.

GREENVILLE which includes vertical beams for altitude and depth measurement. As a failsafe, the AUV can use an internal compass in the event that a problem Saluda COUNTY occurs with the DVL. Vertical accuracy of the DVL at depths of 0 to 200 ft is ±0.4 ft (YSI, Incorporated, 2011). River North In shallow areas (generally less than 3 ft), areas containing debris, or any area otherwise difficult for theAUV to maneuver, the bathymetric SOUTH CAROLINA data were collected with digital echo sounding equipment attached to a manned boat. The data were collected by interfacing a 220-channel global navigation satellite system (GNSS) receiver and data logger to a dual-frequency fathometer and used methods described in Nagle and others (2009). Horizontal accuracy of both GPS types is typically less than 3 ft. The echo sounding equipment also was used as a quality-control 29 check on selected AUV transects. The time measurement accuracy of echo sounding equipment typically is rated by manufacturers at ±0.1 ft 178 plus 0.1 to 0.5 percent of the depth (U.S. Army Corps of Engineers, 2002). To assess potential outliers and erroneous depth data, all data were PICKENS post-processed and imported into a three-dimensional program called ArcScene. Data that were determined to be erroneous were removed from COUNTY further processing and analysis. Using a GIS, the data then were used to create a triangulated irregular network (TIN), which digitally represents a Saluda 25 82°23'30" surface (Environmental Systems Research Institute, 2013). Using methods described by Johnson and others (2008), the TIN was used to produce contour maps at 10-ft intervals and stage-volume relations. All GIS processing was accomplished by using Environmental Systems Research

Greenville SPARTANBURG Institute (Esri) GIS software, including ArcScene, ArcMap, and 3-D Analyst extension (Environmental Systems Research Institute, 2013). COUNTY Water-quality data were collected simultaneously with the bathymetric data by using a bulkhead-mounted multiparameter sonde that is part of the AUV. The water-quality data were used to assess the spatial variability of water temperature, pH, specific conductance, and 123 dissolved-oxygen concentrations. During the period of study, water-quality conditions in the reservoir were relatively uniform with minimal 1,150

River variability; therefore, no maps of the water-quality conditions were produced. Statistical summaries of the water-quality data are provided for the 276 reservoir. In addition, near-surface and near-bottom measurements of water-quality conditions were made periodically and assessed to determine N if changes in water quality occurred vertically in the water column. These water-quality data were collected using a hand-held multiparameter ANDERSON COUNTY sonde from a manned boat. All water-quality sensors were calibrated prior to and after the deployment according to procedures outlined by YSI 1,200 and the USGS National Field Manual (YSI, Incorporated, 2011; Wilde, variously dated; respectively). ESRI® Data & Maps, 2010 0 2 4 6 8 MILES North American Datum of 1983 Universal Transverse Mercator projection, zone 17 0 2 4 6 8 KILOMETERS 82°22'30"

Figure 1. Location of Table Rock and North Saluda Reservoirs and Lake Keowee, Greenville County, South Carolina. Bathymetry and Storage Volumes

The maximum depth recorded in North Saluda Reservoir was 149.5 ft (fig. 2). Side-scan sonar did not indicate any obvious sediment buildup and, similar to Table Rock Reservoir, the relic stream channel was distinct throughout the reservoir. North Saluda Reservoir is considered 35°9'30" to be at full pool when the surface elevation reaches 1,230 ft. Reservoir volume at this level was determined to be 3,181 x 106 cubic feet (ft³) 35°9'30" (table 1; fig. 3). During the data-collection period, the highest recorded surface elevation was 1,230.3 ft.

82°23'30" 82°23'

82°22'30" 82°25'

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82°24'

1,200 1,150

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35°9'

1,200 1,100 1,150 35°9' Selected References

0 0.125 0.25 0.50 MILE Environmental Systems Research Institute, 2013, ArcGIS Help 10.1: Redlands, Calif., Environmental Systems Research Institute, accessed 0 0.125 0.25 0.50 KILOMETER December 10, 2013, at http://resources.arcgis.com/en/help/main/10.1/index.html#//00qn0000001p000000. 1,200 Gesch, D.B., 2007, The national elevation dataset, in Maune, D., ed., Digital elevation model technologies and applications—The DEM users SCALE 1:6,000 manual (2d ed.): Bethesda, Md., American Society for Photogrammetry and Remote Sensing, p. 99–118.

1,150 Lambert Conformal Conic projection Gesch, Dean, Oimoen, Michael, Greenlee, Susan, Nelson, Charles, Steuck, Michael, and Tyler, Dean, 2002, The national elevation dataset: 1,200 82°23'30" North American Datum of 1983 Photogrammetric Engineering and Remote Sensing, v. 68, no. 1, p. 5–11. Greenville Water, 2011, 2011 Water quality report, 4 p., accessed December 10, 2013, at http://www.greenvillewater.com/wp-content/ uploads/2013/02/waterquality.pdf. 1,150 Johnson, M.R., Andersen, M.J., and Sebree, S.K., 2008, Hydrographic surveys for six water bodies in eastern Nebraska, 2005–07: U.S. Geological Survey Scientific Investigations Report 2008–5048, 5 p. 82°24'30" Nagle and others, 2009, Bathymetry of lake William C. Bowen and Municipal Reservoir #1, Spartanburg County, South Carolina, 2008: Water-Quality Conditions U.S. Geological Survey Scientific Investigations Map 2009–3076, 1 sheet. U.S. Army Corps of Engineers, 2002, Engineering and design—Hydrographic surveying, Publication No. EM 1110-2-1003, chap. 9, 3 p., Spatial variability of water-quality conditions were assessed in North Saluda Reservoir for April 15–18, 2013. Subsequent data were accessed December 10, 2013, at http://140.194.76.129/publications/eng-manuals/EM_1110-2-1003_pfl/toc.htm. 82°24' collected on June 12, 2013, in order to add more depth data in targeted areas of the reservoir. Data collection targeted a depth of 2 to 6 ft except in areas where depth exceeded the sensor range. The only instance where depth exceeded the sensor range occurred in the area near the dam out U.S. Geological Survey, 2007, Facing tomorrow’s challenges—U.S. Geological Survey science in the decade 2007–2017: 141/2° to approximately 2,000 ft upstream from the dam where depths reached nearly 150 ft. In order to collect these data, the AUV was programmed U.S. Geological Survey Circular 1309, 70 p. to operate in this target area at a depth of 35 ft. As mentioned previously, water-quality conditions were relatively uniform and demonstrated minimal spatial variability. Wilde, F.D., ed., variously dated, Field measurements: U.S. Geological Survey Techniques of Water-Resources Investigations, book 9, chap. A6, EXPLANATION In North Saluda Reservoir, during the 4-day, data-collection period in April, water-quality data were collected near the surface at depths of with sec. 6.0–6.8, accessed December 10, 2013, at http://water.usgs.gov/owq/FieldManual/Chapter6/Ch6_contents.html.

North o

Magnetic 2 to 6 ft. The water temperature ranged from 14.2 to 18.1 C (table 2), and pH ranged from 5.6 to 6.8. Specific conductance was higher in North True North True Depth, in feet Wilson, G.L., and Richards, J.M., 2006, Procedural documentation and accuracy assessment of bathymetric maps and area/capacity tables for 0 Saluda Reservoir when compared to Table Rock Reservoir, ranging from 23 to 24 microsiemens per centimeter (µS/cm), and dissolved oxygen small reservoirs: U.S. Geological Survey Scientific Investigations Report 2006–5208, 14 p. Approximate mean ranged from 10.2 to 10.7 milligrams per liter (mg/L). declination, 2011 In order to determine vertical changes in the water column, a hand-held multiparameter sonde was used periodically to collect near-surface YSI, Incorporated, 2011, 6-Series multiparameter water quality sondes user manual: YSI, Incorporated, accessed December 10, 2013, at Boat dock and near-bottom water-quality data. In North Saluda Reservoir, near-surface and near-bottom measurements of water temperature (16.6 and http://www.ysi.com/media/pdfs/069300-YSI-6-Series-Manual-RevH.pdf. 82°25' 8.3 oC, respectively) demonstrated a temperature change with depth (table 3). As was observed in Table Rock Reservoir (plate 1), pH, specific conductance, and dissolved-oxygen concentrations in this reservoir were unaffected by the thermal stratification and had fairly constant 150 measurements at both near-surface and near-bottom depths (table 3). For additional information, please contact the Director, South Carolina Water Science Center, email: [email protected], or 1,200 Bathymetric contour–Line of equal lake-bottom visit http://sc.water.usgs.gov/. 35°8'30" elevation, in feet above National Geodetic 35°8'30" Vertical Datum of 1929. Prepared by the Science Publishing Network, Raleigh Publishing Service Center Intervals are 10 feet 1,100 Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. 1,150 Figure 2. Bathymetric map of North Saluda Reservoir, Greenville County, South Carolina, April 2013. 82°24'30" 1,200 Acknowledgments If printed, dimensional calibration may vary between electronic plotters and between X and Y directions on the same plotter, and paper may change size due to atmospheric conditions; therefore, scale and proportions may not be true on plots of this map. NORTH SALUDA DAM 82°24' The authors would like to recognize the contributions of Greenville Water for providing boats and staff to assist in data collection. Suggested citation: Clark, J.M., Journey, C.A., Nagle, D.D., and Lanier, T.H., 2014, Bathymetric maps and water-quality profiles of Table Rock and North Saluda Reservoirs, Greenville County, South Carolina: U.S. Geological Survey Scientific Investigations Map 3289, 2 plates, http://dx.doi.org/10.3133/sim3289.

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