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TECHNIQUES FOR ESTIMATING MAGNITUDE AND FREQUENCY OF FLOODS IN SOUTH CAROLINA, 1980010 U.S. GEOLOGICAL SURVEY Water-Resources Investigations Report 91-4157 a .2 f! d tion with the , Q e in coopera 70VTH CAROLINA DEPARTMENT OF G GB701. HII(GHWAYS AND PUBLIC TRANSPORTATION B 701 W375 no D.91- 415@7 CONVERSION FACTORS AND VERTICAL DATU4 Multiply By To obtain inch (in.) 2.54 centimeter foot (ft) 0.3048 meter mile (mi) 1.609 kilometer square mile (Mi2) 2.590 square kilometer cubic foot per second 0.02832 cubic meter per second (ft3/S) foot per mile (ft/mi) 0.1894 meter per kilometer acre-foot 1,233 cubic meter Sea level: In this report, "sea level" refers to the National Geodetic Vertical Datum of 1929--a geodetic datum derived from a general adjustment of the first-order level nets of the United States and Canada, formerly called Sea Level Datum of 1929. TECHNIQUES FOR ESTIMATING MAGNITUDE AND FREQUENCY OF FLOODS IN SOUTH CAROLINA, 1988 By Wladmir B. Guimaraes and Larry R. Bohnan U.S. GEOLOGICAL SURVEY Water-Resources Investigations Report 91-4157 Prepared in cooperation with the SOUTH CAROLINA DEPARTMENT OF HIGHWAYS AND PUBLIC TRANSPORTATION co M C7) Columbia, South Carolina LIBRARY 1992 NOAA/CcRii 1990 H013SON AVE. C"A-9- SC 29408-2623 U.S. DEPARTMENT OF THE INTERIOR MANUEL LUJANv JR., Secretary U.S. GEOLOGICAL SURVEY Dallas L. Peck, Director For additional information Copies of this report may be write to: purchased from: District Chief U.S. Geological Survey U.S. Geological Survey Books and Open-File Reports Section Stephenson Center-Suite 129 Federal Center 720 Gracern Road Box 25425 Columbia, SC 29210 Denver, CO 80225 CONTENTS Page Abstract ............................................................. 1 Introduction ......................................................... 1 Purpose and scope ............................................... 2 Previous investigations ......................................... 2 Description of study area ....................................... 3 Observed flood data .................................................. 5 Synthesized flood data ............................................... 6 Method of flood-frequency analysis at gaging stations ................ 6 Method of regionalization ............................................ 10 Flood frequency at ungaged sites on*streams draining one physiographic province ......................................... 13 Accuracy of equations ........................................... 20 Limitations .......... 20 Application of regionai*eq ions ............................... 22 Maximum floods of record ........................................ 22 Flood frequency at ungaged sites on streams draining more than one physiographic province .................................... 25 Flood frequency at or near a gaged site on the.same streams in one physiographic province ............................................. 25 Flood frequency at gaged sites on streams draining more than one physiographic province .................................... 27 Broad River ...................................................... 29 Little Pee Dee River ............................................ 32 Lynches River ................................................... 33 Edisto River .................................................... 34 Flood frequency at gaged sites on regulated streams ................... 34 Pee Dee River ................................................... 36 Catawba River ................................................... 37 Wateree River ................................................... 38 Saluda River .................................................... 38 Congaree River .................................................. 39 Santee River .................................................... 39 Savannah River .................................................. 40 Pacolet River ................................................... 41 Frequency of storm tides along the South Carolina coast .............. 41 Summary ............................................................... 42 Selected references .................................................. 43 Supplemental data .................................................... 45 ILLUSTRATIONS Page Figure 1. Map showing physiographic provinces and locations of streamflow gaging stations in South Carolina and parts of North Carolina and Georgia ................ 4 2-11. Graphs showing: 2. Flood-frequency relation for Little Pee Dee River at Galivants Ferry ................................ 10 3. Relation between drainage area and 100-year discharge for stations on streams draining the Piedmont physiographic province in South Carolina, North Carolina, and Georgia ............. 14 4. Relation between drainage area and flood discharge for selected frequencies for stations on streams draining the lower Coastal Plain physiographic province ............................ 16 5. Relation between drainage area and flood discharge for selected frequencies for stations on streams draining the upper Coastal Plain physiographic province ............................ 17 6. Relation between drainage area and flood discharge for selected frequencies for stations on streams draining the Piedmont physiographic province ...... 18 7. Relation between drainage area and flood discharge for selected frequencies for stations on streams draining the Blue Ridge physiographic province .... 19 8. Relation between drainage area and observed maximum flood discharge for South Carolina stations and the regional relations for the 100- and 500-year floods at ungaged sites on streams draining the lower Coastal Plain physiographic province ........ 23 9. Relation between drainage area and observed maximum flood discharge for South Carolina stations and the regional relations for the 100- and 500-year floods at ungaged sites on streams draining the upper Coastal Plain physiographic province ........ 23 10. Relation between drainage area and observed maximum flood discharge for South Carolina stations and the regional relations for the 100- and 500-year floods at ungaged sites on streams draining the Piedmont physiographic province ................... 24 iv ILLUSTRATIONS--Continued Page 2-11. Graphs showing: 11. Relation between drainage area and observed maximum flood discharge for South Carolina stations and the regional relations for the 100- and 500-year floods at ungaged sites on streams draining the Blue Ridge physiographic province ................. 24 12. Map showing locations of gaging stations on regulated streams and gaging stations on streams draining more than one physiographic province in South Carolina ...... 28 13. Graph showing relation between drainage area and 100-year flood discharge for Broad River near Gaffney, Broad River near Carlisle, and Broad River at Richtex ............................................. 30 TABLES Table 1. Weighted flood discharges for selected recurrence intervals for rural streamflow stations used in regionalization study ............................ - 133-174 2. Distribution of stations used in the regionalization analysis with observed flood data by state and physiographic province .................................. 5 3. Flood-frequency data derived from synthesized peak discharges used in the regionalization analysis, and weighted flood-frequency data for rural streamflow stations used in the regionalization study ............. 7 4. Flood-frequency equations for ungaged sites on streams in South Carolina ....................................... 15 5. Equivalent years of record and standard error of prediction for flood-frequency equations ................ 21 v TECHNIQUES FOR ESTIMATING MAGNITUDE AND FREQUENCY OF FLOODS IN SOUTH CAROLINA, 1988 By Wladmir B. Guimaraes and Larry R. Bohman ABSTRACT Methods are provided for estimating the magnitude and frequency of floods on ungaged, unregulated rural streams with drainage areas greater than 0.6, 4.4, 0.1, and 0.6 square miles for the lower Coastal Plain, upper Coastal Plain, Piedmont, and Blue Ridge physiographic regions of South Carolina, respectively. Data from 174 gaging stations in or near South Carolina with 10 or more years of record through September 30, 1988, and 4 stations with synthesized streamflow records were used in the analyses. The frequency of peak discharges at these stations was computed by fitting the logarithms of the annual peak discharges at each station to a Pearson type III distribution or by a graphical method. Frequencies of peak discharges were regionalized by using generalized least squares regression techniques to define the relation of magnitude and frequency of flood discharges to various basin characteristics. The analyses indicated that the contributing drainage area is the only significant basin characteristic necessary to determine peak discharge at selected recurrence intervals. Rural relations are presented for four physiographic regions: (1) lower Coastal Plain, (2) upper Coastal Plain, (3) Piedmont,and (4) Blue Ridge. A table of weighted peak discharges for selected recurrence intervals for all gaging stations in South Carolina, Georgia, and North Carolina used in the regionalization analysis also is presented. Flood-frequency analyses were-also made for gaging stations that drain basins, which spans more than one physiographic province. A supplemental data section contains gaging station information; Pearson type III and graphical frequency statistics; information on stage-discharge relations; and annual peak discharges. INTRODUCTION The U.S. Geological Survey (USGS), in cooperation with state and local agencies, has made many studies to estimate flood frequency and magnitude in rural basins. Information on flood frequency and magnitude is needed for the economic and safe design of bridges, culverts, embankments, dams, levees, and other structures at or near a stream. Flood-frequency information also is essential for effective flood-plain management and for setting appropriate flood insurance rates. The U.S. Water Resources Council (1981) presented a standardized method for estimating the magnitude of flood discharges for various recurrence intervals at gaged sites. This method, along with the most recent regionalization techniques, were used in this investigation to provide the user in South Carolina with the best possible estimates of flood magnitude and frequency at gaged and ungaged sites on unregulated streams. This report was prepared by the USGS in cooperation with the South Carolina Department of Highways and Public Transportation and is based primarily on data collected by the USGS as part of a cooperative stream gaging program with various State and Federal agencies. Most of the data for small streams were collected as part of a separate program with the South Carolina Department of Highways and Public Transportation And the Federal Highway Administration. Purpose and Scope This report presents methods for estimating the magnitude and frequency of floods in South Carolina at ungaged rural sites and provides frequency information at gaged sites on unregulated rural streams. All flood data in South Carolina through September 1988 were analyzed. Data from bordering states (Georgia and North Carolina) were also included in the data base. The report includes: 1. Equations and graphs for estimating the magnitude and frequency of flood discharge on ungaged, rural, non-regulated streams. 2. A method for estimating flood discharge and frequency at or near gaged sites on the same rural streams. 3. Flood discharge and frequency for selected sites on the main stems of major streams with drainage basins located in more than one physiographic province. 4. A compilation of annual flood peaks at gaged sites on streams in South Carolina. Previous Investigations The earliest descriptions of flood frequency of streams in South Carolina were those made by Speer and Gamble (1964), who presented methods for estimating the magnitude of flood discharges for various recurrence intervals for streams in the South Atlantic slope basin. The area covered by their work extended from the James River in Virginia to the Savannah River along the South Carolina-Georgia State line. A more comprehensive treatment of flood frequency for streams in the State was that by Whetstone (1982), who presented methods of estimating flood magnitude and frequency that were based on streamflow data compiled through 1978. This report incorporates flood data used by these earlier investigations and includes additional flood data collected through 1988. 2 Description of Study Area The study area includes all of South Carolina which is located on the South Atlantic slope adjacent to the Atlantic Ocean. The state has an area of 31,055 square miles, and lies in parts of three physiographic provinces, (1) the Blue Ridge, (2) the Piedmont and, (3) the Coastal Plain (Cooke, 1936). The Coastal Plain is divided into the upper Coastal Plain and the lower Coastal Plain. The physiographic provinces and locations of data collection sites in South Carolina and in adjacent areas in North Carolina and Georgia are shown in figure 1. The Blue Ridge physiographical province in South Carolina consists of dissected, rugged mountains with narrow valleys. The land-surface elevation ranges from 1,000 to more than 3,500 ft above sea level. The steep terrain contains some areas where stream gradients exceed 250 ft/mi. Overlying the crystalline bedrock is a layer of weathered bedrock or saprolite. Although some rainfall infiltrates the saproli.te layer, the steep sideslopes and semipermeable soils in this region cause much of the rainfall to run off rapidly into stream channels. Seventy percent of the area is forested with a mixture of oak, hickory, and pine (S.C. Water Resources Commission, 1983, p. 12 and 53). In the Piedmont physiographic province, land slirface elevations range from about 1,000 ft above sea level at the Blue Ridge foothills to about 400 ft at the upper Coastal Plain boundary. Rolling hills, elongated ridges, and moderately deep to shallow valleys are typical land forms. The drainage pattern is well developed with stream gradients ranging from about 5 to 60 ft/mi. The Piedmont is underlain by fractured crystalline rock consisting, of intrusive granite and gneiss, schist and metamorphosed volcanic rock. Most overlying soil is moderately to poorly permeable silty clay loams. Alluvial deposits of clay, silt, and sand occur along the valley floors (Bloxham, 1981, p. 2-4). The upper Coastal Plain physiographic province in South Carolina is characterized by gradual slopes and rounded summits although there are several areas of intensely irregular terrain. Stream gradients range from 5 to 20 ft/mi. Some hilltop elevations exceed 700 ft above sea level at the boundary between the upper Coastal Plain and the Piedmont but commonly are less than 200 ft above sea level at the boundary of the lower Coastal Plain. Extensive swamps and very wide flood plains are common to the four large through-flowing rivers (Bloxham, 1976, p. 3-5). In the lower Coastal Plain physiographic province, the land surface slopes from elevations of about 200 ft above sea level near the boundary of the upper Coastal Plain to the sea. Topographic relief in this area is much less than that in other areas of the state, and small stream drainage patterns are characteristically more erratic in the seaward direction. Stream gradients range from about 20 ft/mi near the upper boundary to 1 ft/mi near the coast. Swamplands associated with large portions of the river systems occupy much of the province. The highly permeable soils in this region are similar to those of the upper Coastal plain, which readily absorb rainfall and retard runoff to stream channels. Streamflows, therefore, rise and fall gradually (Bloxham, 1981, p. 4). 3 80* 780 171 jao,A-@A . . .... 173 72, @k \-L 8 1@,. v r- -,A -169A 138f, AJ.@j A 6 i64,4 166 1 2 5 9 160 163- 33A 3 -111i4l 114@tTD Cw9 1 fAl @'Az4 70 i-32j iA A:50( 124 17.@'A, "'w( :@24 8 414 lk44 A12@ 0 -X4 -A 1 5 > 1 -7 L 1 7 1 9 68 55@ gsA 8a\ 86 A '56 \i 66 !@41 @1, A:i@ 941 @.jR C 4 'A 94 A 102 9 3.9 3 EV 34' go J *5 109 \10 196 J183 Tz. 9 f i 117 7 "A116 -A4'8 'A8 49 k7 0 -77\ 54A A, 'A,55 5 A 12 EXPLANATION N, A,, Alo 13A 16 #A 17 APPROXIMATE AREA WHERE REGIONAL EQUATIONS DO NOT APPLY 16A Al PHYSIOGRAPHIC PROVINCE BOUNDARY -A@2,10 N A32 GAGING STATION WITH OBSERVED DATA AND STATION INDEX NUMBER NJBO GAGING STATION WITH SYNTHESIZED DATA AND STATION INDEX NUMBER 32* - STATION WITH OBSERVED #175 GAGING DATA THAT WAS OMITTED FROM THE 0 2 0 40 60 MILES REGIONALIZATION AND STATION A, 2 INDEX NUMBER 0 20 40 60 KILOMETERS 3 7 Figure l.--Fhysiographic provinces and locations of streamflow gaging stations in South Carolina and parts of North Carolina and Georgia. OBSERVED FLOOD DATA Techniques for estimating peak discharge for a specific rec urrence interval are based on the assessment of long-term flood records. The first streamflow data collected in the study area was for the Savannah River at Augusta, Ga. The U.S. Weather Bureau, now the National Weather Service, began collecting data at this site in 1884. By 1930, streamflow data were collected at a network of sites by the USGS in cooperation with the South Carolina State Highway Department. The data collection program continued to expand and by 1988 data from 174 gaging stations on streams in South Carolina and adjacent areas of North Carolina and Georgia were available for analysis. Each station used in this analysis had at least 10 years of record and the data were not substantially affected by regulation or urbanization. Data for these stations were used in the development of regionalized flood-frequency relations presented in this report. The supplemental data section of this report contains for each of these stations: a station description; the drainage area; the type of data recorder; extreme gage heights and discharges; a description of the stage-discharge relation; and annual peak stages and discharges for the period of record. Flood-frequency data derived from the peak discharges are also included in the supplemental data. The discharges presented in table 1 (at back of report) are the weighted discharges computed for each site using regression equations and the individual station flood-frequency.data. The distribution of gaging stations used to develop these regression equations are presented by state and physiographic province in table 2. Table 2.--Distribution of stations used in the regionalization analysis with observed flood data by state and physioqraphic province Physiographic South North province Carolina Carolina Georgia Total Lower Coastal Plain 11 17 12 40 Upper Coastal Plain 12 9 5 26 Piedmont 25 25 27 77 Blue Ridge 4 18 9 31 Totals 52 69 53 174 Five stations for which streamflow data are available were not included in the regionalization analysis for various reasons (fig. 1). Three stations (map index numbers 175, 176, 177, station numbers 02197300, 02197310, and 02197315, respectively) in the Upper Three Runs basin of the upper Coastal Plain physiographic province were omitted because this basin is flatter, has more deeply incised channels, and has fewer tributaries to the main stream than other basins in the same province. 5 As would be expected, peak discharges for selected recurrence intervals are much lower for the Upper Three Runs basin than for other basins in the upper Coastal Plains province. The regionalized flood-frequency equations devloped for the upper Coastal Plain province do not apply'to this basin or to other basins physiographically similar to the Upper Three Runs basin. Miller Creek Tributary near Baldoc, S.C. (map index number 178, station number 02197410) was not used in the regional analysis because of incomplete data. Dutchman Creek near Pauline, S.C. (map index number 179, station number 02159600) also was not used because the stage-discharge relation at this station was not defined for the higher discharges. SYNTHESIZED FLOOD DATA Long-term discharge records are not always available at a site; however, if concurrent rainfall data are available, a rainfall-runoff model may be used to extend the records. Frequency data for four stations used in this report were from a study by Whetstone (1982) in which the USGS Rainfall-Runoff Model (Dawdy and others, 1972) was used to synthesize a series of annual peak discharges. The model utilizes ten parameters to simulate the hydrologic processes of antecedent soil moisture, infiltration, and surface-runoff routing. Daily rainfall, evaporation, unit-value discharge, and rainfall data from several storm events collected over a period of 3 to 5 years were used to calibrate the model for each of the four basins. Long-term precipitation and evaporation data (more than 50 years of record) were then used to synthesize a series of annual peaks for use in subsequent frequency analyses. Synthesized flood discharges for these stations are not listed in this report; however, flood-frequency data derived from the synthesized discharges are listed in table 3 along with the weighted discharges computed for each site using the appropriate regression equations for each physiographic province and individual station flood-frequency data. METHODS OF FLOOD-FREQUENCY ANALYSIS AT GAGING STATIONS A frequency analysis of annual peak-flow data at gaging stations provided relations between the magnitude of the peak flow and its recurrence interval or probability of occurrence. These relations were regionalized to provide flood-frequency data at ungaged sites and were used to define flood frequency for specific sites on streams draining more than one physiographic province. Probability of occurrence is the percentage chance that a flood of a specific magnitude will be equaled or exceeded in any one year. Recurrence interval (the reciprocal of the probability of occurrence) is the average time interval, in years, between floods that equal or exceed a given magnitude. For example, a flood with a 100-year recurrence interval may be expected to be equaled or exceeded an average of once in 100 years. Stated another way, it is a flood that has a 1 percent probability of being 6 Table 3.--Flood-frequency data derived from the synthesized peak discharges used in the regionalization analysis and weighted flood-frequency data for rural streamflow stations used in the reqionalization study Map Station Drainage Physiographic Type of index name area province data number and (square Flood discharges in cubic feet per second number miles) indicatied recurrence interval in years 2 5 10 25 50 100 180 Crabtree Swamp 14.0 Lower Stationl 206 389 544 780 987 1,220 near Conway, S.C. Coastal weighted 2 247 450 607 872 1,060 1,310 (02110700) Plain- 181 Reedy Creek near 10.4 Lower Station' 244 478 677 977 1,240 1,520 Rains, S.C Coastal weighted 2 244 472 658 939 1,190 1,450 (02135050i Plain 182 Buck Branch at 11.9 Lower Station 213 439 633 925 1,180 1,450 Bowman, S.C. Coastal Weighted 2 238 464 648 935 1,170 1,440 (02174300) Plain 183 Log Creek near 1.26 Piedmont Station 41.0 93.0 141 220 293 378 Edgefield, S.C. Weighted 2 51.0 123 181 276 358 445 (02195660) The station data are computed by fitting the logarithms of annual peak discharges to a Pearson Type III distribution. 2The weighted data are computed by weighting the station data with discharges computed using the regional flood-frequency relations. The weighted data should be used rather than the station data. equalled or exceeded in any given year. The risk of exceeding the 1-percent chance flood magnitude increases with time periods longer than 1 year. During any 50-year period there is about a 40 percent chance, and for any 90-year period there is about a 60 percent chance of one or-more floods exceeding the 1-percent chance flood magnitude. In 1981 the U.S. Water Resources Council developed and published standard guidelines for determining flood magnitude and frequency. The report (Bulletin 17B) defines a uniform method of fitting the logarithms of annual peaks at each site to a Pearson Type III frequency distribution. This distribution is defined by three statistical parameters; the mean, the standard deviation, and the skew. The peak discharge for a given recurrence interval can be computed using the following equation from Bulletin 17B: log QT = X + K S, (1) where QT is the estimate of the T-year flood from the log-Pearson Type III distribution, in cubic feet per second; is the mean of the logarithms of the annual maximum discharges; K is the a scale factor that is a function of the skew coefficient and recurrence interval; and S is the standard deviation of the logarithms of the annual maximum discharges. The accuracy of the station skew coefficient, as an estimate of the true skew of the frequency distribution, is generally a function of the length of the record. The station skew is a measure of the past history of annual floods, and may be unreliable when computed from periods of record less than 10 years because of extreme floods that may be included in the record. The generalized skew coefficient for an area is the average of the station skew coefficients of sites having at least 25 years of streamflow records. By weighting the station skew and the generalized skew, the 8 effects of extreme floods can be dampened. It is recommended in Bulletin 178 that the station skew and generalized skew be weighted inversely to their respective mean-square errors as follows: Gw MSEG(G) + MSEG(G) (2) MSE- + MSE G G where Gw is the weighted skew coefficient; MSE_ is the mean-square error of generalized skew G coefficient; G is the station skew coefficient; MSE is the mean-square error of station skew coefficient; G and 0 is the generalized skew coefficient. The USGS computer program J407, described by Kirby (1979), was used to compute the relation between flood magnitude and probability of occurrence. Program J407 includes the features described in Bulletin 17B, but requires the user to exercise judgment when providing data on historic peaks, specifying screening levels for outliers, and interpreting the appropriateness of the resultant frequency curve to the observed data set. The weighted skew coefficient was used for most stations. The weighted or station skew coefficients used in the flood-frequency analyses are listed in the Supplemental Data section as appropriate for all stations in South Carolina. The graphical method documented by Dalrymple (1960) was used at several stations where the logarithms of annual peaks could not be fitted to a Pearson Type III distribution. For example, abrupt changes in storage in unregulated streams can cause abrupt changes in the flood-frequency relation, such as where the flow moves from a deeply incised channel to a broad floodplain. Circumstances at specific stations requiring use of the graphical method are documented in the supplemental data section of this report. A typical flood-frequency relation is shown in figure 2. 9 100,000 0 z 0 W IL 0 10,000 U z 1,000 L J i L L _L _L _L L I L J _L 99.99 9.9 99.8 99 98 95 90 80 70 60 50 40 20 10 5 2 1 30 0.5 0.2 0.1 EXCEEDANCE PROBABILITY, IN PERCENT Figure 2.--Flood-frequency relation for Little Pee Dee River at Galivants Ferry, S.C. (map index number 188, station number 02135000). METHOD OF REGIONALIZATION Flood-frequency information is needed at many sites that are ungaged. Flood-frequency information can be transferred from a gaged site to an ungaged site using the regression method as described by Riggs (1973). The discharge for a given frequency, for example, can be related to physical and climatic basin characteristics. Multiple regression analysis provides a mathematical relation between@a single response variable (the 2- to 500-year flood) and any number of explanatory variables (drainage area, channel slope, and so on). Numerous studies have indicated that if the logarithmic transformation of peak discharge and basin characteristics are used, the relation between them will be linear. To facilitate the regression analyses presented in this report, all flood peaks and basin characteristics were transformed to their logarithmic values before multiple regression analyses. The significance of each explanatory variable (basin characteristic) to the regression was assessed in this study by its ability to decrease the standard error of the regression and to increase the coefficient of determination (R-squared). For this study, a 95-percent confidence limit was used to select the significant variables. 0 10 Initially, exploratory regression analyses were made using an ordinary least squares step-forward"' regression technique to find the most significant variables. In thistype of analysis, the most highly-related variable is determined, then another variable is added and the standard error and coefficient of determination are computed with both explanatory variables included in the predictive equation. This process is continued until all significant variables are selected. The ordinary least squares (OLS) regression method has been traditionally used in the past for regionalization. This method is based on the assumptions that the residuals from the regression are homoscedastic and independent of each other. The assumption of homoscedacity means that the variance of the residuals remains constant regardless of which time period is used to compute the data being regressed. Obviously, this assumption is violated because different flood-frequency relations and variances will be obtained for differing periods of record. This is called the time-sampling error. Because the flood-frequency relation has time-sampling error, the OLS regression method will also have time-sampling error. Also, the assumption of independence of the residuals from each other is violated, because many of the flood events used to derive the flood-frequency relations are cross-correlated, because they experience the same climatic events (G.D. Tasker, A.M. Lumb, W.O. Thomas, and K.M. Flynn, U.S. Geological Survey, written commun., 1987). Recent research by Stedinger and Tasker (1985, 1986) has indicated that generalized least squares (GLS) may be more appropriate for hydrologic regression. Their Monte Carlo analysis showed that the GLS technique was superior to the OLS technique when streamflow data were cross correlated or of different record lengths. In the generalized least squares technique, each basin data set in the regional regression analysis is weighted appropriately by taking into consideration the variance (time-sampling error). The spatial correlation structure of the streamflow characteristic is also accounted for in evaluating the accuracy of the regression equation. The prediction error for ungaged sites is partitioned into model error (error in assuming an incomplete model form) and sampling error (including both time- and spatial-sampling errors). The model error cannot be reduced by additional data collection, but the sampling error can be reduced by operating the existing stations longer or by installing new stations or some combination of both. The hydrologic model is of the form: b c QT = ABaC D ... where QT is the flood magnitude having T-year recurrence interval; A is a constant; B,C,D are basin characteristics (explanatory variables); and a,b,c are regression coefficients. The hydrologic model also has a linear form as follows: log QT = log A + a log B + b log C + c log D+... This logarithmic relation is the form that was used in this study. In some cases Isqualitative variables" were included in the model to differentiate between physiographic provinces. An example of the linear form of the model including qualitative variables is: log Qt = log A + a log B + b log C + c log D + + dV where V is a qualitative variable that is set to zero if the variable is in province "x" or one if in province "y". If the qualitative variable is determined to be significant by the regression analysis, the regression line for the two provinces have the same slope, but different intercepts. The qualitative variable was used to detect significant differences between provinces and to utilize data from both provinces where data were sparse. The basin characteristics used in the regionalization study are described below. These variables were found to be significant in at least some of the exploratory regression analyses. Other explanatory variables were tested but were not statistically significant. 1. Drainage area, A, in square miles, as determined from the best available topographic map. 2. Channel slope, SL, in feet per mile, is the average slope between points located at 10 and 85 percent of the main channel length upstream from the gage to the basin divide. 3. Length of main channel, L, in miles, is the distance along the length of the stream from the gage to the basin divide. 12 4. Storage, ST, in percent, is the percentage of the drainage.area that is covered by lakes, ponds, and swamps. 5. L/SL0*5, ratio of length in feet to the square root of slope, in feet per mile. FLOOD FREQLJENCY AT UNGAGED SITES-ON STREAMS DRAINING ONE PHYSIOGRAPHIC PROVINCE Flood frequency at ungaged sites was determined using the OLS and GLS regression-methods. An ordinary least squares regression for exploratory purposes was first made using data from every station in the study area. A geographical bias was.detected; floods in the mountainous regions of South Carolina were underpredicted while those in coastal regions were overpredicted. Four regional boundaries were then delineated using a residual map, geologic and soils maps, and previous flood frequency studies (Whetstone, 1982). Next, separate regression analyses were made using data from each of the four provinces (fig. 1). Drainage area was found to be the most significant variable. Main channel length, main channel slope, and basin storage were found to be significant at the 95 percent confidence level for some recurrence intervals and some provinces. The addition of these variables to the regression equations, however, did not improve the standard error by more than 3 percent and therefore, these variables were not included in any of the regression equations. Within each physiographic province, the 100-year discharge was regressed against the explanatory variables and a qualitative variable that denotes location by state. These regressions indicated that Georgia and North Carolina Piedmont data were not significantly different from each other, but were both significantly different from South Carolina Piedmont data, as shown in figure 3. Note that the South Carolina data in figure 3 plots generally below the data points from Georgia and North Carolina. Inclusion of the qualitative variable allows the data from all three states to influence the slope of the overall relation, and at the same time permits a unique intercept value for the South Carolina relation. Although it is possible to use only South Carolina data in the regression, the relation using the data from all three states with the qualitative variable was considered to be more definitive because of the sparseness of the South Carolina data for stations with drainage areas less than about 20 Mi2. The explanatory variables determined as significant in the ordinary least squares analyses Were then used.in the generalized least squares regression procedures. The 2-, 5-, 10-, 25-, 50-, 100-, and 500-year flood-frequency equations that resulted are listed in table 4. Graphs were also prepared for ease in computing the discharge estimates and are shown in figures 4-7. The upper coastal plain physiographic province tends to have lower discharges than any other physiographic region because the soil consists mainly of sand that has high infiltration and low runoff potential. 13 1 OQ 000 z Ui 0 REGRESSION EQUATION 00 FOR NORTH CAROLINA AND GEORGIA M W 40 10,000z 0 1P 0 0 UW 0 REGRESSION EQUATION 0 FOR SOUTH CAROLINA 0 W W LU LL 1,000 0 EXPLANATION 00 o GEORGIA 1 00-YEAR DISCHARGES z n NORTH CAROLINA 100-YEAR DISCHARGES o SOUTH CAROLINA 100-YEAR DISCHARGES 100 11111 0.1 1 10 100 1,000 DRAINAGE AREA. IN SQUARE MILES Figure 3.--Relation between drainage area and 100-year discharge for stations on streams draining the Piedmont physiographic province in South Carolina, North Carolina, and Georgia. Table 4. --Flood- frequency equations for ungaged sites on streams in South Carolina Flood discharge QTP in cubic feet per second, for Regression equations for the indicated physiographic provinces recurrence interval T, Lower Coastal Upper Coastal Piedmont Blue Ridge in years Plain Plain Q2 56A0* 63 25A 0.74 127A 0 . 66 103A 0 .79 Q5 111A 0.61 44A 0.72 211A 0.64 196A 0.76 0.59 0.71 0.64 0.73 Q10 = 157A 59A 267A 286A 0.59 0.70 0.63 0.70 Q25 = 221A 80A 347A 429A Q50 = 275A 0.58 97A 0.70 410A 0.63 558A 0.69 0.58 0.69 0.63 0.67 QIOO = 335A 116A 474A 705A 0.52 0.66 0.63 0.63 QSOO = 569A 179A 615A 1,150A 15 100,000 4'.", fmiil J ii!llf i. I@, 1 + $;E @il: T! R iT, !1,1'!11;`N,11_ I ii lilt, z It it IT'll it It L Ali., 4' 4! W iti I "t,t 1 0,000 i'@_ it ofi i'l T f., M'i InIlOrlif ll, V, 1111. 11, 1 @li "t-, ill",Y 4 W V rill '11- P tit 22 v.- 1E .1litt 3 W 1 It fit W :T it U. 11ri 41111- Yj 4-1i 1,000 4 . . ... ... . ON z rt Iff, 4tf t 17 1 Ld 2-IT, _400@z I t @t 111 'Tr: le it . ..... [email protected]@ il fill! 4i A j-fjr . it Iiii, ii 11, 100 A pit .7t.11 4li; x it . .... ..... ,ir. .... ... . .. 4@i it T;lf if if! 11 irt Or j @ I I I 4i t 1 1 J -1 if 10 0. 1 1 10 100 1,000 10,000 DRAINAGE AREA, IN SQUARE MILES Figure 4.--Relation between drainage area and flood discharge for selected frequencies for stations on streams draining the lower Coastal Plain physiographic province. 100,000 . . . . . . . . . .W Elm Nil _55 T`q@f 4U z 7W I.J W 411 7rT.: 10,000 ,10 LU TIT Pit 2T .. . ....... 775 4, LU H LU LL OK FE 1 it 1,000 gi; ;@ g. ki tit it. 114.4 itu. flu 0 A 114 100 011 '41-1421"Tarli 7, @T, -j, .01"I li,@ MIA @t IT Tfild HU t@i yl- LM I @t 10 T r 0.1 1 10 100 1,000 10,000 DRAINAGE AREA, IN SQUARE MILES Figure 5.--Relation between drainage area and flood discharge for selected frequencies for stations on streams draining the upper Coastal Plain physiographic province. 100,000 .t; .11 UE T;;! 4@ z JU. . ..... ..... .V, W Plt7 mln"' W 10,000 41 Mill,!1 W ft Ott! Wit, in W Ir 4-fl LL i @iET 1,000 -H z L.1i T j CD 11-@ rl I 100 16 x au"@; ;f fig -t 14 r, 'ji @j! ft it fir.: i2! 1111ilH 10 0.1 1 10 100 1,000 10,000 DRAINAGE AREA, IN SQUARE MILES Figure 6.--Relation between drainage area and flood discharge for selected frequencies for stations on streams draining the Piedmont physiographic province. 100, 000 i!M!, NIT ff Fjt It it z 1:14 1:1 . ...... 74 Hit W -7 It i :,1. 2 W; @t 10,000 it, 1;! fi;l 4,til 1141@ Ij 191 t tt:1 LU RAN 1,01 !i%. 0 W Zl.-41111fl. t t :41 NO Val PM it W 41 fir:, .... . . ..... W Ti, LL pj@ U it Pli 1,000 -MACUP'l IF T @Allrlaf-;- -1 N., Ell t 'T 14 z -tt 7 il tH+ if fi P@ IIATA' 11 IM i: M fl-l: E.", t H1 MiT -P 4o Lj 14 ..1.- 11H @7-1- . I , it tit: Hill" tt@ 7i 4! i, H 100 -i Z 41 h 14,155 ;S t,.t::t LTT ;M@ if U-I-JiFl!@i,' U J E 1. .1 5M WA tEl. 11i i ti 10 - 0.1 1 10 100 1,000 10,000 DRAINAGE AREA, IN SQUARE MILES Figure 7.--Relation between drainage area and flood discharge for selected frequencies for stations on streams draining the Blue Ridge physiographic province. Accuracy of Equations The accuracy of the regression equations may be measured by the standard error of prediction and in equivalent years of record. These values are listed in table 5 for all the regression equations derived for use in South Carolina. The prediction error for ungaged sites is partitioned into model error and sampling error (including both time- and spatial-sampling errors). The model error is that portion of the total error (prediction error) that cannot be reduced by additional data collection. The sampling error, however, can be reduced by operating the existing stations longer, or by installing new stations, or some combination of both. The average variance of prediction (sum of average sampling error variance and average model error variance) can be converted to an average standard error of prediction such as that shown in table 5. The standard error of prediction resulting from the regression analyses ranged from 23 percent for the 2-year flood in the upper Coastal Plain to 53 percent for the 2-year flood in the Piedmont province. The equivalent years of record (Hardison, 1971) is defined as the number of years of streamflow records needed to provide an estimate equal in accuracy to the regional relation. For instance, the 100-year flood-frequehcy equation for the Lower Coastal Pl 'ain has a value of 10 years for the equivalent years of record (table 5). Therefore, the 100-year flood can be estimated from the regression equations with the same degree of accuracy, on the average, that could be obtained from 10 years of actual record. The equivalent years of record resulting from the regional relations ranged from 1 year to 22 years for the 2- and 500-year floods, respectively, in the Piedmont province. Limitations The following guidelines apply when using the regression equations and graphs: 1. Tne equations should be used only for ungaged sites where the basin drainage area is between 0.6 and 1,252 mil for the lower Coastal Plain, 4.4 and 1,720 mil for the upper Coastal Plain, 0.1 and 1,430 mil for the Piedmont, and 0.6 and 945 mil for the Blue Ridge physiographic provinces. 2. The equations should not be used for sites where the watershed is substantially affected by regulation from impoundments, channelization, levees, or other man-made structures. 3. The equations should not be used for sites on streams in urban areas unless the effects of urbanization are insignificant. 4. The equations should be used with caution in areas where the streamflow characteristics have not been sufficiently defined by flood measurements (fig. 1). In York and Chester Counties, the regional equations tend to produce discharge results that may be significantly lower than those obtained using discharge records. 20 Table 5.--Equivalent years of record and standard error of prediction for flood-frequency equations Flood discharge Lower Coastal Plain Upper Coastal Plain Piedmont Blue Ri.dge QT, in Equivalent Standard Equivalent Standard Equivalent Standard Equivalent Standard cubic feet years of error of years of error of years of error of years of error of per second record prediction record prediction record prediction record prediction for (percent) (percent) (percent) (percent) recurrence interval T, in years Q 2 5 30 5 23 1 53 3 32 Q 5 7 31 8 25 4 38 5 31 IQ Q10 8 34 10 26 7 31 8 30 Q25 9 40 12 29 12 29 11 31 Q50 9 44 13 31 15 28 12 33 Q100 10 47 14 33 18 28 13 35 Q 500 14 47 15 39 22 30 15 40 5. The equations should be used with caution in the Upper Three Runs basin in Aiken and Barnwell counties in the western part of the Upper Coastal Plain physiographic province. The regional equations tend to produce discharges that may be significantly higher than those obtained using observed discharge records in the Upper Three basin. To obtain flood discharges for the Upper Three Runs basin, either the station discharge should be used (Supplemental data) or the discharge at an ungaged site should be adjusted by drainage area. Application of Regional Equations Flood magnitude and frequency for ungaged rural basins in South Carolina can be estimated by solving the regional equations provided in table 4 or by using the graphs presented in figures (4-7). The location of regional boundaries are shown in figure 1. Step-by-step procedures for determining the magnitude and frequency of flood discharges are given below. 1. Determine that discharge at the site is not affected by regulation, urbanization, channel improvement, diversion, or tide. 2. Determine the drainage area of the basin upstream of the site using the best avaiable topographic map or aerial photograph. 3. Determine the physiographic province (see fig. 1) in which the drainage basin is located. For basins located near a boundary between physiographic provinces, consult a soils map to determine the proper physiographic province and associated equations. 4. Using the appropriate equations in table 4, solve for the discharge. For a 50_Mi2 watershed in the Upper Coastal Plain, the 100-year flood discharge can be computed as follows: Qloo = 116AO *69 = 116(50)0 .69 = 1,720 ftl/s Maximum Floods of Record The drainage area and the maximum known flood for sites on streams in the lower Coastal Plain,.upper Coastal Plain, Piedmont, and Blue Ridge physiographic provinces in South Carolina are shown in figures 8-11, respectively. Lines representing the solutions of the 100- and 500-year flood equations are also shown in these figures for purposes of comparison. 22 100,000 z 0 W W 10,000 W W z 1,000 01 W 0 100, 1 10 100 1,000 10,000 DRAINAGE AREA, IN SQUARE MILES Figure B.-Relation between drainage area and observed maximum flood discharge for South Carolina stations and the regional relations for the 100- and 500-year floods at ungaged sites on streams draining the lower Coastal Plain physiographic province. 100,000 T I T ITIrr- I I I I fill[ I I I I I It z 0 W W 11 1.. 10,000 W III 1,000 100 1 10 100 1,0W 10,000 DRAINAGE AREA. IN SQUARE MILES Figure 9.--Relation between drainage area and observed maximum flood discharge for South Carolina stations and the regional relations for the 100- and 500-year floods at ungaged sites on streams draining the upper Coastal Plain physiographic province. 23 Q Cl 8) CL (D CL --') CD- (D Fl P. " 0 P. 0) " (f) F-1 (n F- Fl. 0 0 CD D rt, Z)- DISCHARGE. IN CUBIC FEET PER SECOND Z). r-f- ZT .1 p. :T W I DISCHARGE. IN CUBIC FE 0 (D p 07 0) (D " I (o ;o CD (D -CD (D (D 0 CD CD 0 (D C@l Z)7 0 (D 1 0 (D 1 0 cu w 0 _0 w 0 :3 Ln :3 :3 (f) :3 0- 0 (D Cl 0 c 07 c 0- r-t- (D rt (D 0 ZY, rt 0 0 zT rt 0 :F- D Q cl I (-) (D rt, (c) @< w (D @ <1 n (D (D (D Fj > CD, W CD '0 (D " :) w 0 z a) o z @o 1--.CL > CL > a 0 LA p. " 0 l< Z) W. m P. -t =1 W m U) Q) p 0 1-- w P. p. 0 (o 0 ::) )o 0 0 (h w Fj 0 U) W m (c 0L rtl(o m W c)- c-t-(o m Fj (j) 0) (D z -0 (n W (D 13) rlt- r"t -0 0) H. @-- 13) ::r r-t- 0 0 c-t- 0 " P. Z) (D M Z) (D 0) 0 C (f) w 0 -0 c U) w lo :3 _0 (0 w a) c c H w > 0 (c) w a) o(o CL 0- < (1) m (o 0- 0- m rt. 0 Z) (1) 0 c)- rt 0 ZT CY ::r 0- F Q V) CD (n m CD W (D (n m CD, (D (D P. (D CD, Fj " 0 rt, " Fj M (D (D < (D (D < (f)(0 (D W (0 (D P. 0- P. a - 00 00 3 3 U) x X rt rt, -C> cl) cl) (D CD, (D F- U) r-t- -t U) rt -t p. I-- Fl- @- el 00 00 ::) 0 ::) 0 Ln CL U) a FLOOD FREQLENCY AT UNGAGED SITES ON STREAMS DRAINING MORE THAN ONE PHYSIOGRAPHIC PROVINCE If the drainage area of the ungaged basin is located in more than one physiographic province, solve the appropriate equations for each physiographic province as though the drainage area were located entirely in each province, and then weight the discharge as described below. For example, if the drainage area is 100 square miles with 60 percent of the basin located in the Piedmont, and 40 percent in the Blue Ridge, computation of the 100-year discharge is as follows: Piedmont: Qloo = 474(100) 0.63 = 8,630 .x 60 percent = 5,18O.ft'/s Blue Ridge: Q100 = 705(100) 0.67 = 15,400 x 40 percent = 6,160 ft3/S Sun 11,300 ft3/S FLOOD FREQUENCY AT OR NEAR A GAGED SITE ON THE SAME STREAM IN ONE PHYSIOGRAPHIC PROVINCE Flood magnitude and frequency can be determined for gaged sites in South Carolina by weighting the results of the regression relations (table 4), or graphs (figs. 4-7), and the gaging station frequency data (supplemental data in appendix 1) determined by fitting the log of the annual peaks to a Pearson Type III distribution. Assuming that the two estimates are independent, the accuracy in equivalent years for the weighted estimate is equivalent to the sum of the accuracy of each estimate. The best estimate of flood discharges at a gaged site can be determined from the following equation: 109 QT(w) = Nlog QT(s) + EY109 QT(r) (3) N+EY where QT(w) is the weighted discharge for selected T-year recurrence interval, in cubic feet per second; N is the number of years of record used to compute QT(s); QT(s) is the station discharge for selected T-year recurrence interval, in cubic feet per second; EY is the equivalent years of record for QT(r) from table 6; and; QT(r) is the regional discharge for selected T-year recurrence interval, in cubic feet per second. 25 Weighted station flood discharges for selected recurrence intervals (2, 59 10, 25, 50, and 100 years) using table 4, table 5, and equation 3 for all stations used in the regression analysis are listed in table 1. The weighted values shown were computed using all available data through 1988 and supersedes values previously published by Whetstone (1982). -These weighted values are considered the best estimates for design purposes. Flood discharges for selected recurrence intervals (2, 59 10p 25, 50, and 100 years) computed from peak flows synthesized from a rainfall-runoff model were also weighted with flood-frequency data from the regression equations of table 4. Equivalent years for the synthetic peak discharges were estimated from a regression of synthetic T-year floods as a function of rainfall-runoff model parameters made by Lichty and Liscum (1978) and modified by Thomas (U.S. Geological Survey,, written commun., May 1991). The equivalent years for synthetic flood data are listed below: Recurrence intervals Equivalent years (years) of record 2 5 5 10 10 15 25 20 50 21 100 23 These data, the data in table 4 and equation 3, were used to compute the weighted discharge in table 3 for stations with synthesized peak-flow data. Flood-frequency estimates at sites near a gaging station on the same stream can be improved by transferring the nearby weighted station data to the ungaged site (adjusted estimate) and weighting it with the regression data for the ungaged site. The adjusted estimate is determined first as follows: b Q Qg(w) (4) u = (@g- and the final weighted value can be computed by the equation Q Q 2,&A Qu) (5) u(w) = (I@g_) n A 26 ERRATASHEET FOR U.S. GEOLOGICAL SURVEY WATER-RESOURCES INVESTIGATIONS REPORT 91-4157 PLEASE REPLACE PAGE 26 WITH ATTACHED PAGE. Weighted station flood discharges for selected recurrence intervals (2, 59 109 25, 50, and 100 years) using table 4, table 5, and equation 3 for all stations used in the regression analysis are listed in table 1. The weighted values shown werecomputed using all available data through 1988 and supersedes values previously published by Whetstone (1982). These weighted values are considered the best estimates for design purposes. Flood discharges for selected recurrence intervals (2, 5, 10, 25, 50, and 100 years) computed from peak flows synthesized from a rainfall-runoff model were also weighted with flood-frequency data from the regression equations of table 4. Equivalent years for the synthetic peak discharges were estimated from a regression of synthetic T-year floods as a function of rainfall-runoff model parameters made by Lichty and Liscum (1978) and modified by Thomas (U.S. Geological Survey, written commun., May 1991). The equivalent years for synthetic flood data are listed below: Recurrence intervals Equivalent years (years) of record 2 5 5 10 10 15 25 20 50 21 100 23 These data, the data in table 4 and equation 3, were used to compute the weighted discharge in table 3 for stations with synthesized peak-flow data. Flood-frequency estimates at sites near a gaging station on the same stream can be improved by transferring the nearby weighted station data to the ungaged site (adjusted estimate) and weighting it with the regression data for the ungaged site. The adjusted estimate is determined first as follows: Q (Au bQ (4) u Ag g(w) and the final weighted value can be computed by the equation Qu(w 1 A@@g Qn + (I 2AA Qu (5) A9 26 -Where, QU is the adjusted discharge at the ungaged site transferred from the gaged site by the drainage area ratio, in cubic feet per second. Qg(w) is the weighted discharge for the nearby gaging station, in cubic feet per second. Qn is the discharge using regional relation for ungaged sites, in cubic feet per second. Qu(w) is the weighted discharge at the ungaged site, in cubic feet per second. b is the drainage area exponent of the regional relation from table 4 for the applicable physiographic province. A is the drainage area of ungaged site, in square miles. u A9 is the drainage area of gaged site, in square miles. .AA is the difference in drainage area between the gaged site and the ungaged site, in square miles. This procedure should only be used to transfer flood discharge if the drainage area of the ungaged site near a gaged site is within 50 percent of the drainage area of the gaged site. If it is not, use of the regional regression equations as described in the previous section will provide the best estimate of flood discharge. FLOOD FREQLENCY AT GAGED SITES ON STREAMS DRAINING MORE THAN ONE PHYSIOGRAPHIC PROVINCE Flood frequencies for gaged sites on unregulated streams draining one physiographic province are presented in table-1. Gaging stations located on streams draining more than one physiographic province in South Carolina are shown in figure 12 and are described in unnumbered text tables that follow. Some of these streams are subject to minor regulation that does not significantly affect annual peak discharges. The logarithm of annual peak discharge values for these stations were fitted to a Pearson Type III distribution to determine flood discharges for selected reccurrence intervals. This type of analysis was made for stations on the Broad River, Little Pee Dee River, Lynches River, and Edisto River. 27 82, so, 131LT-TIE I:ZIDCw]E 19 4 @41' 'S,A 185 E: 1@ib C, -1 - 2 9 19 188 05 -34* 9 19 6 202 OD 2 01 7 200 "r @T- 0 d, 9 EXPLANATION F-HYS104GRAPHIC PROVINCE 0 20 4101 60 MILES BOUNDARY r A191 GAGING STATION AND 0 20 40 60 KILOMETERS STATION INDEX NUMBER 32" Figure 12.--Locations of gaging stations on regulated streams and gaging stations on streams draining more than one physiographic province in South Carolina. Broad River The Broad River originates in the Blue Ridge province of North Carolina and flows eastward and southward through the Piedmont to Columbia, S.C., where it merges with the Saluda River to form the Congaree River (fig. 12). Floods on the Broad River consist primarily of unregulated runoff, although there is some regulation at low to medium flows. Flood discharges were computed for Broad River near Gaffney (map index number 184, station number 02153500, 1939-88); Broad River near Carlisle (map index number 185, station number 02156500, 1939-88); and Broad River at Richtex (map index number 186, station number 02161500, 1926-83). Flood discharges were initially computed for the three stations using the concurrent period of 1939-83. When flood discharge was computed for Broad River at Richtex using the entire period of record, 1926-83, the 100-year discharge increased substantially. The flood records for Broad River near Gaffney and Broad River near Carlisle did not include the extreme flood events recorded at Richtex, which occurred between 1926 and 1939. Therefore, an adjustment was made in accordance with Appendix 7 of U.S. Water Resources Council Bulletin 17B. The mean and standard deviation of the stations with short periods of record were adjusted to agree with the mean and standard deviation of the station with the longer period of record. Statistically, no adjustment was needed for Broad River near Gaffney, but an adjustment for the standard deviation was required for Broad River near Carlisle. The relations between flood discharge and drainage area for Broad River near Gaffney, Broad River near Carlisle, and Broad River at Richtex are shown in figure 13. The unadjusted 100-year flood discharges for all three Broad River stations are shown for the period 1939-83 along-with the adjusted 100-year flood discharge to reflect the period from 1926-83 in figure 13. 29 1,000,000 EXPLANATION z 0FLOOD DISCHARGE 0 - FOR PERIOD 1926-1983 U - 0FLOOD DISCHARGES W FOR PERIOD 1939-1983 0 AADJUSTED FLOOD DISCHARGES FOR BROAD RIVER NEAR CARLISLE W W A W IL 2 loo,ooo - co I W > j X W 'W 2 IL X z L W W W z z z W W W > > > 0 0 0 10,0001 1,0W 10,000 DRAINAGE AREA. IN SQUARE MILES Figure 13.--Relation between drainage area and 100-year flood discharge for Broad River near Gaffney (map index number 184, station number 02153500), Broad River near Carlisle (map' index number 185, station number 02156500), and Broad River at Richtex (map index number 186, station number 02161500). 30 The adjusted flood discharges for selected recurrence intervals are tabulated below for Broad River near Gaffney, Broad River near Carlisle, and Broad River at Richtex. Map Station Drain- Flood discharge, in cubic feet per second, for index name age indicated recurrence interval, in years num- and area ber number (square miles) 2 5 10 25 50 100 184 Broad 1,490 31,500 45,800 57,700 75,900 92,100 111,000 River near Gaffney (02153500) 185 Broad 2,790 41,200 6-4-,000 84,000 115,000 144,000 178,000 River - near Carlisle (02156500) 186 Broad 4,850 59,000 89,700 115,000 153,000 187,000 225,000 Ri v er at Richtex (02161500) 'Flood discharges were adjusted in accordance to Appendix 7 of Water Resources Council Bulletin 17B. 31 Little Pee Dee River The Little Pee Dee River originates in the upper Coastal Plain of North Carolina and flows southward and eastward to the lower Coastal Plain of South Carolina (fig. 12). The Little Pee Dee River, known as the Lumber River in North Carolina, is not regulated. Flood discharges for selected recurrence intervals are tabulated below for Little Pee Dee River near Dillon (map index number 187, station number 02132500, 1940-88) and Little Pee Dee River near Galivants Ferry (map index number 188, station number 02135000, 1942-88). Map Station Drain- Flood discharge, in cubic feet per second, for index name age indicated recurrence interval, in years number and area number (square miles) 2 5 10 25 50 100 187 Little 524 29490 3,880 4,950 6,450 7,690 9,030 Pee Dee River near Dillon (02132500) 188 Little 2,790 12,000 17,600 21,100 25,600 28,900 32,200 Pee Dee River near Galivants Ferry (02135000) 32 Lynches River The Lynches River originates in the Piedmont of North Carolina, and flows southeastward through the upper Coastal Plain to the lower Coastal Plain of South Carolina (fig. 12). The Lynches River is not regulated. Flood discharges for selected recurrence intervals are tabulated below for Lynches River near Bishopville (map index number 189, station number 02131500, 1943-88), and Lynches River at Effingham (map index number 190, station number 02132000, 1930-88)., Flood discharges for the 2-, 5-, and 10-year recurrence interval are smaller for the downstream station, Lynches River near Effingham, because as the Lynches River flows from the upper to lower Coastal Plain the flood peaks are attenuated due to increased storage in the flood plain. Map Station Drain- Flood discharge, in cubic feet per second, for index name age indicated recurrence interval, in years number and area number (square miles) 2 5 10 25 50 100 189 Lynches 675 6,770 10,200 12,400 15,400 17,600 19,800 River near Bishop- ville (02131500) 190 Lynches 1,030 5,610 9,190 11,900 15,800 18,900 22,300 River near Effingham (02132000) 33 Edisto River The North Fork Edisto River and South Fork Edisto River originate in the upper Coastal Plain of South Carolina and flow southeastward to the lower Coastal Plain. The South and North Fork of the Edisto River merge near Branchville in the lower Coastal Plain forming the Edisto River (fig. 12). Flood discharges for selected recurrence intervals for Edisto River near Givhans (map index number 191, station number 02175000, 1939-88) are tabulated below. Map Station Drain- Flood discharge, in cubic feet per second, for index name age indicated recurrence interval, in years number and area number (square miles) 2 5 10 25 50 100 191 Edisto 2,730 10,100 15,400 18,800 22,500 25,900 28,700 River near Givhans (02175000) FLOOD FREQLJENCY AT GAGED SITES ON REGLLATED STREAMS Many streams in South Carolina, especially the larger streams, are regulated by reservoirs. Flood-frequency relations for these streams are dependent on a number of factors and are therefore quite complex. Flows from reservoirs are regulated to satisfy requirements for in-stream water-use downstream of the reservoirs, power generation, maintenance of lake levels for recreation, and flood control. Regulation procedures may change as requirements change or when other reservoirs are constructed on the same stream. In general, flows during operation for flood control pass through tainter gates, whereas flows for most other requirements pass through generators. Operational procedures and the use of storage are greatly different for the two flow regimes. The flood-frequency characteristics of higher and lower magnitude floods are also greatly different. For extremely large floods, not only do the relative effects of storage diminish but,operations are also directed more toward preventing dam failure than toward flood control and protection of downstream property. 34 Sanders and others (1990) showed that the period after 1951 for the Savannah River at Augusta, Ga. (station number 02197000) was significantly free of extremely large floods, based on an unusually long period of flood data (1796-1985). A flood-frequency relation was established for the site using peak discharges computed by the routing of synthesized inflow hydrographs through the reservoirs to the site using current operating conditions. This method produced considerably larger discharges than the frequency relation derived by Whetstone (1982) in which the logarithms of annual peak discharges were fitted to a Pearson Type III distribution for the relatively flood-free period (1952-80). Therefore, to accurately determine the flood frequency of regulated streams, a representative number of extremely large-flood events should be included in the analysis, using methods similar to those used by Sanders and others (1990). Flood frequency data for gaged sites on regulated streams were not determined for this report (except for Savannah River at Augusta, Ga., map index no. 207, station number 02197000) because observed data were not available for hydrograph simulations, and because hydrograph simulation by rainfall-runoff modeling was beyond the scope of the study. The location of USGS gaging stations on regulated streams is shown in figure 12. Annual peak discharge data for these stations are provided in the supplemental data section of this report. Other useful information pertaining to regulated streams for which observed record is available is provided in the following sections. The reservoir data were taken from a report by Ruddy and Hitt (1990). 35 Pee Dee River The Pee Dee River originates in the Blue Ridge province of North Carolina and flows through the Piedmont, upper Coastal Plain, and lower Coastal Plain physiographic provinces (fig. 12). Through most of Nortm Carolina it is known as the Yadkin River. Three reservoirs on the Yadkin River and two reservoirs on the Pee Dee River are used for hydroelectric power generation. A sixth reservoir, located on the Yadkin River, W. Kerr Scott Reservoir, is used for flood control and water supply. Selected data on these reservoirs are listed below. Name Date Name Drainage Flood-storage of of of area capacity reservoir completion stream (square (acre-feet) miles) W. Kerr Scott 1963 Yadkin 350 112,000 Reservoir High Rock Lake 1927 Yadkin 4,000 64,400 Tuckertown 1962 Yadkin 49120 0 Reservoir Badin Lake 1917 Yadkin 4,180 75,800 Lake Tillery 1928 Pee Dee 49600 29,500 Blewett Falls 1912 Pee Dee 6,830 7,000 Lake Annual peak discharge data are available for one gaging station on the Pee Dee River downstream from the lakes. The Pee Dee River at Peedee (map index number 192, station number 02131000, 1939-88) (Supplemental data). 36 Catawba River The Catawba River originates in the Blue Ridge province of North Carolina and flows through the Piedmont province of South Carolina and becomes the Wateree River below Lake Wateree (fig. 12). Ten reservoirs, six in North Carolina and four in South Carolina, are located on the Catawba, River and are storage facilities for hydroelectric power generation. Selected data on eight of these reservoirs are presented below. Name Date Drainage area Flood-storage of of (square capacity reservoir completion miles) (acre-feet) Lake James 1919 380 67,900 Rhodhiss Lake 1925 1,090 50p2OO Lake Hickory 1928 1,310 6lpl4O Lookout Shoals 1915 l-,450 6,240 Lake Lake Norman 1963 1,790 182,000 Mountain Island 1923 1,860 23,300 Reservoir Lake Wylie 1900 3,020 33,000 Fishing Creek 1916 3t810 0 Reservoir Annual peak discharge data are available for the Catawba River near Rock Hill (map index number 193, station number 02146000, 1963-88) and Catawba River near Catawba (map index number 194, station number 02147000, 1968-88) (Supplemental data). 37 Wateree River The Wateree River originates at the outflow of Lake Wateree, which was built on the Catawba River. The Wateree River flows southeastward through the upper Coastal Plain where it merges with the Congaree River to form the Santee River (fig. 12). Lake Wateree is used for hydroelectric power generation. Selected data for Lake Wateree are presented below. Station Date Drainage Flood-storage name of area capacity completion (square miles) (acre-feet) Lake Wateree 1919 4,750 45,100 Annual peak discharge data are available for Wateree River near Camden (map index number 195, station number 02148000, 1963-88) (Supplemental data). Saluda River The'Saluda River originates in the Blue Ridge province and flows through the Piedmont province of South Carolina where it merges with the Broad River near Columbia forming the Congaree River (fig. 12). Two reservoirs, Lake Greenwood and Lake Murray, are located on the Saluda River. Selected data for these reservoirs are presented below. Name Date Drainage area Flood-storage of of (square capacity reservoir completion miles) (acre-feet) .Lake Greenwood 1940 1,150 147,000 Lake Murray 1930 29420 1259000 The Saluda River above Lake Greenwood is not affected significantly by regulation. Flood discharges for drainage areas less than Boo Mi2 in this part of the basin should be determined as described in previous sections of this report by (1) estimating flood discharge at an ungaged site, or (2) estimating flood discharge at or near a gaged site. The three gaging 38 qtotions on the Saluda River upstream from Lake Greenwood (fig. 1) are Saluda River near Greenville (map index number 82, station number 02162500, 1942-78), Saluda River near Pelzer (map index number 83, station number 02163000, 1930-77), and Saluda River near Ware Shoals (map index number 84, station number 02163500, 1939-78). Records also are available for three stations downstream from Lake Greenwood. These are Saluda River at Chappells (map index number 196, station number 02167000, 1927-88), Saluda River near Silverstreet (map index number 197, station number 02167500, 1927-65), and Saluda River near Columbia (map index number 198, station number 02169000, 1926-88) (Supplemental data). Congaree River The Congaree River is formed at the confluence of the Broad River and Saluda River at Columbia, S.C. The Congaree River flows southeastward and joins the Wateree River to form the Santee River (fig. 12). The Broad River basin comprises approximately two-thirds of the drainage area of the Congaree River. Flow of the Congaree River is highly regulated by Lake Murray, which is located on the Saluda River. Annual peak-discharge data are available for the Congaree River at Columbia (map index number 199, station number 02169500) (Supplemental data). Santee River Formed at the confluence of the Congaree and Wateree Rivers, the Santee River flows directly into Lake Marion - the largest reservoir by surface area in the State. Flood-storage Name of Date of Drainage area capacity reservoir completion (square miles) (acre-feet) Lake Marion 1941 14,680 255,000 Since 1941, most of the discharge from Lake Marion has been diverted to the Cooper River through a diversion canal to Lake Moultrie (fig. 12). A rediversion canal, completed in 1986, restores approximately 80 percent of the previously diverted flow back to the Santee River. Due to the extensive hydrologic modification, which has taken place over the last 40 to 50 years, frequency computations were not made for stations along the Santee River. However, annual peak discharges for the four stations with 10 or more years of record are listed in the supplemental data section; Santee River at Ferguson (map index number 200, station number 02170000, 1908 to 1941), Santee River near Pineville (map index number 201, station number 02171500, 1942 to current year), Santee River near Russellville, (map index number 202, station number 02171560, 1978 to current year), Santee River below St. Stephens (map index number 203, station number 02171650, 1971 to 1981) (Supplemental data). 39 Savannah River The Tugaloo and Seneca Rivers, which originate in the Blue Ridge province, converge to form the Savannah River. The Savannah River is the state boundary between Georgia and South Carolina and is regulated by three reservoirs along its main stem. The reservoirs are operated by the U.S. Army Corps of Engineers for flood control, generation of power, and navigation. Data pertaining to the reservoirs are listed below (Sanders and others, 1990). Name Date Drainage area Flood-storage of of (-quare capacity reservoir completion miles) (acre-feet) Lake Hartwell 1960 2,088 293,000 Richard B. 1984 2@900 140,000 Russell Lake Strom Thurmond 1953 6,150 390,000 Lake Frequency data for Savannah River at Augusta (map index number 207, station number 02197000) recently published in USGS Water-Resources Investigations Report 90-4024 (Sanders and others, 1990), are tabulated below. Map Station Drain- Flood discharge, in cubic feet per second, for index name age indicated recurrence interval, in years number and area number (square miles) 2 5 10 25 50 100 207 Savannah 7,508 34,500 51,500 69,000 105,000 140,000 180,000 River at Augusta (02197000) 40 Annual peak-discharge data for five other stations with 10 or more years of record on the Savannah River are listed in the supplemental data section of this report; Savannah River near Iva (map index number 204, station number 02187500, 1949 to 1981), Savannah River near Calhoun Falls (map index number 205, station number 02189000, 1900 to 1979), Savannah River near Clarks Hill, S.C. (map index number 206, station number 02195000, 1940 to 1954), Savannah River at Burtons Ferry Bridge near Millhaven, Ga. (map index number 208, station number 02197500, 1930 to current year), and Savannah River near Clyo, Ga. (map index number 209, station number 02198500, 1925 to current year). Pacolet River The Pacolet River originates in the Blue Ridge province and flows southeastward to'the Piedmont Province where it merges with the Broad River (fig. 12). The South Pacolet River is regulated by Lake William C. Bowen, and the North Pacolet River is unregulated. Selected data for the reservoir are presented below. Name Date Drainage area Flood-storage of of (-quare capacity lake completion miles) (acre-feet) William 1956 79.4 99600 C. Bowen Annual peak-discharge data are available for Pacolet River near Fingerville (map index number 210, station number 02155500, 1903-88), and Pacolet River near Clifton (map index number 211, station number 02156000, 1940-78) (Supplemental data). FREQUENCY OF STORM TIDES ALONG THE SOUTH CAROLINA COAST The magnitude and frequency of discharges presented in previous sections of this report do not apply where flooding is influenced by extreme tidal events. The theoretical frequency of storm-tide elevations along the South Carolina coast has been investigated by Myers (1975) and more recently in a series of flood-insurance studies by the Federal Emergency Management Agency (1986, 1987, 1988, 19899 1991). These references should be consulted for information related to storm tide frequency. 41 SUMMARY Flood frequencies were determined from observed streamflow data at 174 gaging stations on rural, unregulated streams and from synthetic record at 4 additional stations on rural, unregulated streams by fitting the logarithm of annual peak discharges to a Pearson type III distribution or by graphical methods. Fifty-six of these gaging stations were in South Carolina, and 122 were near the South Carolina border, in either North Carolina or Georgia. Regional relations between flood discharge and drainage area were determined by generalized least squares regression analyses for each physiographic province. Equations, maps, and graphs are provided for estimating flood discharges with recurrence intervals of 2, 5, 10-, 25, 50, 100, and 500 years on ungaged streams in South Carolina. Standard errors of prediction for the regional equations ranged from 23 to 53 percent. Flood discharges at gaged sites can be computed using a weighted average of the discharge determined from regional regression equations and, the discharge determined from the Pearson type III analysis for the gaging station. Methods for estimating flood discharges for sites on gaged and ungaged streams that drain in more than one physiographic province are also presented. A weighting method for determining peak discharges at sites at or near gaging stations on the same stream is given. Relations between flood discharges and recurrence interval are presented for gaging stations on streams draining more than one physiographic province. A supplemental data section provides the data used in the frequency analyses. Included in this section are annual peak stages, and discharges, frequency and statistical data, and a station description for each gaging station with 10 or more years of data on streams in South Carolina. 42 SELECTED REFERENCES Bennett III, C.S., 1984, Impact of the proposed 1-326 crossing on the 500-year flood stages of the Congaree River near Columbia, South Carolina: U.S. Geological Survey Water-Resources Investigation Report 84-4280, 23 p. Bloxham, W.M., 1976, Low-flow characteristics of streams in the inner Coastal Plain of South Carolina: South Carolina Water Resources Commission, Report No. 5, 31 p. 1981, Low-flow characteristics of ungaged streams in the Piedmont and lower Coastal Plain of South Carolina: South Carolina Water Resources Commission, Report No. 14, 48 p. Cooke, C.W., 1936, Geology of the Coastal Plain of South Carolina: U.S. Geological Survey Bulletin 867, 196 p. Dalrymple, Tate, 1960, Flood-frequency analyses, Manual of Hydro logy: Part 3., Flood-Flow Techniques: U.S. Geological Survey Water-Supply Paper 1543-A, 80 p. Dawdy, D.R, Lichty, R.W., and Bergmann, J.M., 1972, A rainfall-runoff simulation model for estimation of flood peaks for small drainage basins: U.S. Geological Survey Professional Paper 506-8, 28 p. Federal Emergency Management Agency, 1986, Flood Insurance Study, unincorporated areas, South Carolina, Beaufort County: Federal Emergency Management Agency, Flood Insurance Study, 29 p. ----- 1987, Flood Insurance Study, unincorporated areas, South Carolina, Colleton County: Federal Emergency Management Agency, Flood Insurance Study, 22 p. 1988, Flood Insurance Study, unincorporated areas, South Carolina, Horry County: Federal Emergency Management Agency, Flood Insurance Study, 49 p. 1989, Flood Insurance Study, unincorporated areas, South Carolina, Georgetown County: Federal Emergency Management Agency, Flood Insurance Study, 51 p. ----- 1991, Flood Insurance Study, unincorporated areas, South Carolina, Charleston County: Federal Emergency Management Agency, Flood Insurance Study, 53 p. Hardison, C.H., 1971, Prediction error of regression estimates of stream-flow characteristics at ungaged sites, in U.S. Geological Survey Research 1971: U.S. Geological Survey Professional Paper 750-C, p. C228-C236. Kirby, W., 1979, Log-Pearson Type III flood-frequency analysis using guidelines of Water Resources Council (Program J407): U.S. Geological Survey WATST9RE User's Guide, v. 4, chap. I-C, 57 p. 43 SELECTED REFERENCES--Continued Lichty, R.W., and Liscum, Fred, 1978, Arainfall-runoff modeling procedure for improving estimates of T-year annual floods for small drainage basins: U.S. Geological Survey Water-Resources Investigations 78-7, 44 p. Myers, V.A., 1975, Storm tide frequencies on the South Carolina coast: National Oceanic and Atmospheric Ackninistration Technical Report, NWS-16, 79 p. Riggs, H.C., 1973, Regional analysis of streamflow characteristics: U.S. Geological Survey Techniques of Water-Resources Investigations, Book 4, Chapter B3, 15 p. Ruddy, B.C., and Hitt, K.J., 1990, Summary of selected characteristics of large reservoirs in the United States and Puerto Rico, 1988: U.S. Geological Survey Open-File Report 90-163, 295 p. Sanders, Jr., C.L., Kubik, H.E., Hoke, Jr., J.T., Kirby, W.H., 1990, Flood frequency of the Savannah River at Augusta, Georgia: U.S. Geological Survey Water-Resources Investigations Report, 90-4024, 87 p. South Carolina Water Resources Commission, 1983, South Carolina State water assessment: South Carolina Water Resources Commission Report No. 140, 367 p. Speer, P.R., and Gamble, C.R., 1964, Magnitude and frequency of floods in the United States, Part 2-A, South Atlantic Slope basins, James River to Savannah River: U.S. Geological Survey Water-Supply Paper 1673, 329 p. Stedinger, J.R., and Tasker, G.D., 1985, Regional hydrologic analysis 1.: Ordinary weighted, and generalized least squares compared: Water Resources Research, (21) 99 p. 1421-1432. ----- 1986, Regional hydrologic analysis 2t Mean-error estimators, estimation of sigman, and log-pearson Type 3 distributions: Water Resources Research, (22) 10, p. 1487-1499. U.S. Water Resources Council, 1981, Guidelines for determining flood flow frequency: U.S. Water Resources Council Bulletin 17B, 183 p. Whetstone, Benjamin, 1982, Technicques for estimating magnitude and frequency of floods in South Carolina: U.S. Geological Survey Water-Resources Investigation Report 82-1, 78 p. 44 I SUPR-B4ENTAL DATA 45 SUPR-EMENTAL DATA Explanation of Tables The following tables contain flood data for streamflow gaging stations in South Carolina. The tables contain a brief description of the gage location, type of gage, gage datun (if known), drainage area in square miles, stage-discharge relation, historical data, hydrologic unit number' and explanatory remarks. The log-Pearson Type III flood-frequency data using either a weighted or station skew coefficient, and adjusted for historic peaks, high and low outliers, and truncated or incomplete record, are given for most stations with 10 or more years of record. The tables of peak stages and discharges show only the annual maximums. Underlined data in these tables signify the following: 1. An underlined entry in the "Water yeare" column indicates discontinuous record. 2. An underlined entry in the "'Gage height" column indicates a change in gage datum and means that the gage height above and below the line are not comparable. 3. Underlined entries in the "Date" and "Discharge" columns indicate a change in the site location that significantly affects the stage-dishcarge relation. 'The hydrologic unit number is determined from a set of maps developed by the U.S. Geological Survey that depict the approved boundaries of river-basin units of the United States (Seaber and others, 1984). These maps and associated codes provide a standardized base for use by water-resources organizations in locating, storing, retrieving, and exchanging hydrologic data; indexing and inventorying of hydrologic data and informaton; cataloging of water-data aquisition activities; and a variety of other applications. 46 WACCAMAW RIVER BASIN 02110500 WACCAMAW RIVER NEAR LONGS, SC LOCATION.--Lat 33*54'45", long 76*4215511, Horry County, Hydrologic Unit 03040206, near right bank, on downstream side of bridge on State Highway 9, 500 ft downstream from Buck Creek, 2.1 mi southeast of Longs, and at mile 85.4. DRAINAGE AREA.--1,110 m12, approximately. PERIOD OF RECORD.--March 1950 to current year. GAGE.--Water-stage recorder. Datum of gage is 5.28 ft above National Geodetic Vertical datum of 1929 (levels of Corps of Engineers). Prior to Aug. 11, 1967, nonrecording gage at same site and datum. REMARKS.--Records good. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 16,200 ft3/s Aug. 23, 1981, gage height, 14.87 ft. STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 11,800 fts/s and graphically extended on logarithmic plotting paper. FLOOD-FREQUENCY DATA (ft3/s) LOG-PEARSON TYPE III STATISTICS (LOG UNITS) 38 YEARS OF RECORD Mean - 3.744 LOG-PEARSON TYPE III Standard Deviation = 0.228 Q = 5,640 Weighted Skew = -0.210 Q = 8,660 Q 10 ' 10,700 Q 5 = 13,400 QQ50 = 15,300 100= 17,300 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year hTight year height 3 year height 3 ft) (ft3/5) (ft) (ft /s) (ft) (ft /a) 1951 Jan. 8 9.41 1,860 1966 Mar. 10 12.64 7,750 1981 Aug. 23 14.87 16,200 1952 Apr. 2 10.05 2,520 1967 Aug. 20 11.73 5,530 1982 Feb. 22 11.97 5,540 1953 Mar. 15 11.50 6,360 1968 Jan. 21 10.42 2,970 1983 Mar. 26 14.40 12,200 1954 Apr. 11 10.00 2,520 1969 Aug. 13 13.26 9,440 1984 Apr. 5 11.50 4,800 1955 Sept.29 13.82 10,300 1970 Mar. 31 11.96 6,060 1985 Feb. 21 11.31 4,250 1956 Feb. 19 9.89 2,230 1971 Mar. 12 12.85 8,300 1986 Aug. 27 9.94 2,150 1957 Mar. 15 10.38 3,780 1972 Feb. 14 12.19 6,100 1987 Mar. 9 12.75 7,550 1958 Apr. 18 12.46 7,540 1973 Feb. 20 13.10 8,620 1988 Jan. 26 10.12 2,440 1959 Mar. 13 13.40 9,760 2974 Aug. 26 12.01 5,720 1960 Aug. 4 13.52 10,000 1975 Feb. 25 11.27 4,240 1961 July 6 13.94 11,100 1976 July 13 11.54 4,780 1962 Mar. 16 11.11 4,520 1977 Mar. 14 10.95 3,630 1963 Feb. 1 11.90 6,180 1978 Jan. 28 11.92 5,540 1964 Mar. 5 12.02 6,200 1979 Sept.16 12.72 7,470 1965 Oct. 17 12.09 6,380 1980 Mar. 24 12.24 6,200 47 FEE DEE RIVER BASIN 02130500 JUNIPER CREEk NEAR CHERAW, SC LOCATION.--Lat 34*39', long 79*54', Chesterfield County, Hydrologic Unit 03040201, at left end of Eureka Lake Dam, 1.5 mi upstream from mouth and 3.5 mi south of Cheraw. DRAINAGE AREA.--64 m12, approximately. PERIOD OF RECORD.--May 1940 to September 1958. GAGE.--Recording. Altitude of gage is 90 ft (from Corps of Engineers maps.) REMARKS.--Records good. EXTREMES FOR PERIOD OF RECORD. --Maximum discharge, 3,910 fts/s, Sept. 18, 1945, gage height, 5.71 ft. STAGE-DISCHARGE RELATION.--Defined by current-meter measurements below 810 ft 3/s andgraphically extended on logarithmic plotting paper and using a computation of flow over dam at 3,190 ft /a. FLOOD-FREQUENCY DATA (ft3 /a) .STATISTICS (LOG UNITS1 18 YEARS OF RECORD Mean - 2.619 GRAPHICAL SOLUTION Standard Deviation - 0.251 Q2 = 365 2Station Skew = 1.374 Q5 = 642 Q10 = 900 Q25 = 11410 Q = 1 980 50 = 2:760 Q100 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height year height 3 year height 3 (ft) (ft3 /a) (ft) (ft Is) (ft) (ft /a) 1941 July 15 1.33 395 1947 Oct. 10 1.32 369 1953 June 9 2.30 Sao 1942 Aug. 20 1.22 332 1948 Feb. 15 1.41 430 1954 Dec. 15 1.20 316 1943 Jan. 20 1.12 295 1949 May 2 1.50 459 1955 Oct. 17 1.01 235 1944 Mar. 22 1.10 286 1950 Nov. 3 1.00 224 1956 Sept.15 360 1945 Sept.18 5.71 3,910 1951 Sept. 8 1.34 392 1957 Sept.12 1.20 316 1946 May 5 1.30 410 1952 Sept. 1 2.05 778 1958 July 22 1.92 712 1 The logarithms of annual peak discharges could not be fitted to a Pearson type III distribution because of regulation at low to medium flows; therefore, a graphical solution was used that followed the systematic record at the lower end and the WRC weighted estimate at the upper end of the flood frequency curve. 2 Station skew computed using graphical frequency relation. 48 PEE DEE RIVER BASIN 02130900 BLACK CREEK NEAR MCBEE, SC LOCATION.--Lat 34*30'50", long 80*1110011, Chesterfield County, Hydrologic Unit 03040201, near right bank, at downstream side of bridge on U.S. Highway 1, 0.2 mi upstream from Little Alligator Creek, 5.3 mi northeast of McBee, and at 5ile 59.1. DRAINAGE AREA.--108 mi . PERIOD OF RECORD.--October 1959 to current year. GAGE.--Water-stage recorder. Datum of gage is 224.72 ft above National Geodetic Vertical Datum of 1929. Prior to December 22, 1959, nonrecording gage at same site and datum. REMARKS.--Records good. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 1,770 ft3/s, July 16, 1975, gage height, 11.29 ft. STAGE-DISCHARGE RELATION.--Defined by current-meter measurements throughout entire range of discharge. FLOOD-FREQUENCY DATA (ft3/3) LOG-PEARSON TYPE III STATISTICS (= UNITS) OF REr 29 YEARS 'ORD Mean - 2. LOG-PEARSON TYPE III Standard Deviation - 0.150 Q 2 = 722 Weighted Skew - 0.059 Q5 = 1.040 Q10 = 11210 Q 25 = 11430 Q = 1 590 50 = 1:76o Q100 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year h7ight year height year height ft) (ft3/s) (ft) (ft3/a) (ft) (ft 3/a) 1960 Apr. 7 9.59 804 1970 Mar. 24 8.83 411 1980 Mar. 31 10.21 1,010 1961 Feb. 26 9.65 840 1971 Aug. 19 10.44 1,120 1981 July 5 9.47 666 1962 Mar. 13 9.76 906 1972 Oct. 4 10.06 930 1982 Jan. 6 9.51 683 1963 Jan. 22 9.37 678 1973 Apr. 2 9.80 800 1983 Mar. 19 10.61 1,240 1964 Mar. 17 10.04 1,070 1974 Aug. 10 8.97 471 1984 Mar. 31 9.21 563 1965 Oct. 18 10.08 1,100 1975 July 16 11.29 1,770 1985 Aug. 27 9.08 517 1966 Mar. 6 9.34 670 1976 June 23 9.51 694 1986 Nov. 23 8.85 440 1967 Aug. 26 9.43 715 1977 Mar. 15 9.68 762 1987 Mar. 2 10.03 921 1968 Jan. 13 9.27 640 1978 Jan. 28 9.51 694 1988 Jan. 21 8.01 286 1969 June 18 10.08 1,110 1979 Feb. 27 10.35 1,090 49 PEE DEE RIVER BASIN 02130910 BLACK CREEK NEAR HARTSVILLE, SC LOCATION.--Lat 34*23150", long 80*09'00", Darlington County, Hydrologic Unit 03040201, at downstream side of bridge on State Road 23, 1,000 ft downstream from dam at H. B. Robinson Steam Electric Plant, 2.1 mi upstream from Beaverdam Creek, 4.6 mi west of Hartsville, and at mile 49.9. DRAINAGE AREA.--173 mi2. PERIOD OR RECORD.--October 1960 to current year. GAGE.--Water-stage recorder. Datum of gage is 177.48 ft above National Geodetic Vertical Datum of 1929. REMARKS.--Records fair. Some regulation by storage in steam electric plant reservoir above station. EXTREMES FOR PERIOD OF RECORD. --Maximum discharge, 2,010 ft3/s, Aug. 18, 1971, gage height, 10.08 ft. STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 1,070 ft3/s and graphically extended on logarithmic platting paper. FLOOD-FREQUENCY DATA (ft3 /s) LOG-PEARSON TYPE III STATISTICS (LOG UNITS1 29 YEARS-OF RECORD Mean - 2.920 LOG-PEARSON TYPE III Standard Deviation - 0.168 Q2 ' 828 Station Skew - 0.095 Q 5 = 11150 Ql = 11370 Q25 = 11660 Q5 = 11880 Q100 - 21100 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height year height year height (ft) (ft3 Is) (ft) (ft3/s) ft) (ft3/a) 1960 Apr. 7 9.59 804 1970 Mar. 23 7.21 505 1980 Mar. 31 8.57 1,160 1961 Feb. 25 8.82 1,060 1971 Aug. 18 10.08 2,010 1981 Aug. 6 6.99 510 1962 Mar. 14 7.93 860 1972 Jan. 14 8.21 915 1982 Jan. 7 8.94 1,360 1963 Jan. 22 8.10 950 1973 June 22 8.34 988 1983 Mar. 20 8.47 984 1964 Mar. 18 8.17 896 1974 Aug. 9 7.40 624 1984 Dec. 7 7.86 741 1965 Oct. 19 8.23 924 1975 July 17 9.52 1,7.40 1985 Feb. 11 7.72 686 1966 Mar. 7 7.60 668 1976 June 27 6.97 541 1986 Nov. 22 7.11 482 1967 Aug. 26 7.67 692 1977 Mar. 25 7.67 770 1987 Mar. 3 8.56 1,160 1968 Jan. 12 7.85 760 1978 Jan. 26 7.69 776 1988 Jan. 25 6.24 347 1969 June 24 7.93 792 1979 Feb. 27 8.59 1,170 50 PEE DEE RIVER BASIN 02131000 PEE DEE RIVER AT PEEDEE, SC LOCATION.--Lat 34*12'15", long 79'32155", Marion County, Hydrologic Unit 03040201, at downstream side of downstream bridge on U.S. Highway 76 at Peedee, 0.2 mi downstream from Seaboard Coast Line Railroad bridge, 8.2 mi downstream from Black Creek, and at mile 100.2. DRAINAGE AREA.--8,830 m12, approximately. PERIOD OF RECORD.--October 1938 to current year. Monthly discharge only for some periods, published in WSP 1303. Prior to October 1947, published as "near Mars Bluff." Gage-height records collected at practically same site since 1923 are contained in reports of National Weather Service. GAGE.--Water-stage recorder and data collection platform. Datum of gage is 24.73 ft above National Geodetic Vertical Datum of 1929. Prior to Oct. 1, 1947, at site 1.6 mi downstream at datum 1.27 ft lower. REMARKS.--Flow regulat%d by six powerplants above station. Combined usable capacity of reservoirs, 30,819,624, 000 ft . EXTREMES FOR PERIOD OF RECORD. --Maximum discharge, 220,000 ft3/s, Sept. 22, 1945, gage height, 33.30 ft (site and datum then in use). STAGE-DISCHARGE RELATION. --Defin7d.by cuirent-meter measurements below 76,000 ft3/s and extended on basis of discharge measurement of 22 00 ft /s at Cheraw, SC. Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height year height year height (ft) (ft3 /s) (ft) (ft3 /s) (ft) (ft3 /s) 1939 Mar. 6 25.61 66,700 1959 Apr. 26 21.44 28,800 1979 Mar. 2 29.03 102,600 1940 Aug. 22 22.35 35,300 1960 Apr. 10 26.28 70,400 1980 Apr. 2 24.11 42,600 1941 Apr. 9 19.32 17,400 1961 Mar. 3 23.86 46,300 1981 July 3 18.72 19,000 1942 Mar. 15 22.26 1962 Jan. 14 22.98 39,300 1982 Jan. 9 22.75 34,100 1943 Feb. 3 22.31 34,400 1963 Mar. 20 24.54 53,400 1983 Mar. 25 24.59 46,000 1944 Mar. 26 24.32 51,800 1964 Apr. 14 23.95 47,600 1984 Apr. 4 26.55 65,200 1945 Sept.22 33.30 220,000 1965 Oct. 23 26.01 62,100 1985 Aug. 29 21.74 29,600 1946 Jan. 4 23.76 45,400 1966 Mar. 10 25.28 57,000 1986 Nov. 28 21.99 30,900 1947 Jan. 26 22.16 30,900 1967 Aug. 29 20.84 26,300 1987 Mar. 7 29.06 96,500 1948 Feb. 19 26.23 69,300 1968 Jan. 19 23.01 36,900 1988 Jan. 20 19.48 20,100 1949 Dec. 5 24.12 47,800 1969 Feb. 27 21.78 32,500 1950 Nov. 7 21.22 25,600 1970 Aug. 19 21.69 31,800 1951 Apr. 14 20.36 21,600 1971 Mar. 10 23.98 47,900 1952 Mar. 10 25.95 62,600 1972 June 29 24.09 47,200 1953 Feb. 28 23.54 39,700 1973 Apr. 6 26.97 74,600 1954 Jan. 29 25.76 60,500 1974 Apr. 12 22.45 35,800 1955 Apr. 21 22.44 32,200 1975 Mar. 20 27.81 85,300 1956 Mar. 22 20.46 22,000 1976 June 26 20.49 23,100 1957 Apr. 13 21.58 30,000 1977 Dec. 20 22.56 36,500 1958 Dec. 1 24.58 52,600 1978 Feb. 1 26.58 70,000@ 51 PEE DEE RIVER BASIN 02131150 CATFISH CANAL AT SELLERS, SC LOCATION.--Lat 34*17104", long 79*26132", Marion County, Hydrologic Unit 03040201, on right downstream wingwall of culvert on State Highway 38, 2.0 mi east of Sellers, 2.3 mi upstream from Stackhouse Creek, and at mile 25.6. DRAINAGE AREA.--27.4 m12. PERIOD OF RECORD.--November 1966 to current year. REVISED RECORDS.--WRD SC-77: Drainage area. GAGE.--Water-stage recorder. Elevation of gage is 75 ft above National Geodetic Vertical Datum of 1929 (from topographic map). REMARKS.--Records good. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 890 fts/s, Mar. 4, 1971, gage height, 9.15 ft. STAGE-DISCHARGE RELATION.--Defined by current-meter measurements throughout entire range of discharges. FLOOD-FREQUENCY DATA (ft3/s) LOG-PEARSON TYPE III STATISTICS (LOG UNITS1 22 YEARS OF RECORD Mean - 2.423 LOG-PEARSON TYPE III Standard Deviation - 0.250 Q - 263 Weighted Skew - 0.085 Q2 = 429 5 = 557 Q10 = 738 Q25 = 887 Q50 1PO50 Q100 = Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height year height 3 year height 3 3 (ft) (ft /a) (ft) (ft /a) ft) (ft /8) 1967 June 24 3.33 67 1977 Mar. 22 5.35 204 1987 Mar. 2 7.25 354 1966 Jan. 11 4.22 120 1978 Jan. 26 5.12 192 1988 Aug. 25 5.17 288 1969 Oct. 20 7.98 413 1979 Sept. 7 @6.51 271 1970 Mar. 23 6.43 260 1980 Apr. 14 15.81 223 1971 Mar. 4 9.15 890 1981 Aug. 14 5.03 222 1972 Feb. 4 4.51 162 1982 June 5 5.96 269 1973 Feb. 15 6.84 304 1983 Mar. 18 9.04 830 1974 Aug. 7 8.39 557 1984 Her. 26 6.09 275 1975 Apr. 3 6.88 308 1985 Sept.12 5.06 223 1976 July 10 4.39 156 1986 Nov. 30 6.06 274 52 PEE DEE RIVER BASIN 02131309 FORK CREEK AT JEFFERSON, SC LOCATION.--Lat 34*38,1911, long 80-2312011, Chesterfield County, Hydrologic Unit 03040202, on upstream side, at center of span on State Highway 151 bridge, 1.0 mi south of intersection of State Highways 765 and 151, at Jefferson. DRAINAGE AREA.--24.3 m12. PERIOD OF RECORD.--October 1976 to current year. GAGE.--Water-stage recorder. Datum of gage is 302.68 ft above National Geodetic Vertical Datum of 1929. REMARKS.--Records good. EXTREMES FOR PERIOD OF RECORD. --Max 'mum discharge, 1,560 fts/s, Feb. 24, 1979, gage height, 7.89 ft. STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 862 ft3/a and graphically extended on logarithmic plotting paper. FLOOD-FREQUENCY DATA (ft3/s) LOG-PEARSON TYPE III STATISTICS (LOG UNITS) 12 YEARS OF RECORD Mean - 2.787 LOG-PEARSON TYPE III Standard Deviation - 0.281 Q2 = 615 Weighted Skew - -0.041 Q 5 = 11060 Q10 - 1,400 Q25 ' 1,880 Q50 = 2,280 Q100 = 2,700 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year h7ight (ft3/.) year height (ft.3 year height 3 ft) (ft) /a) (ft) (ft /a) 1977 Dec. 16 7.36 1,130 1982 Jan. 1 5.96 539 1987 Jan. 19 6.43 694 1978 Jan. 20 6.76 854 1983 Feb. 15 7.73 1,430 1988 Aug. 30 5.90 522 1979 Feb. 24 7.89 1,560 1984 Mar. 29 5.55 432 1980 Mar. 29 6.65 782 1985 Aug. 18 5.37 392 1981 Feb. 11 4.51 256 1986 Nov. 30 4.00 194 53 PEE DEE RIVER BASIN 02131500 LYNCHES RIVER NEAR BISHOPVILLE,SC LOCATION.--Lat 34*15'00", long 80*12150", Lee County, Hydrologic Unit 03040202, near center of span on downstream side of bridge on U.S. Highway 15, 1.0 mi upstream from Seaboard Coast Line Railroad bridge, 2.9 mi northeast of Bisbopville, 3.0 mi downstream from Bells Branch, and at mile 89.5. DRAINAGE AREA.--675 m12. PERIOD OF RECORD.--May, 1942 to current year. GAGE.--Water-stage recorder from May, 1942 to September, 1971. Partial record crest gage from October, 1971 to current year. REMARKS.--Records good except for period of no gage-height record which is poor. EXTREMES FOR PERIOD OF RECORD. --Maximum discharge, 29,400 ft3/s, Sept. 19, 1945. (gage height, 22.35 ft, from floodmark). STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 11,300 fts/s and extended by velocity-area studies. FLOOD-FREQUENCY DATA (ft3/5) LOG-PEARSON TYPE III STATISTICS (LOG UNITS) 45 YEARS OF RECORD Mean 3.824 LOG-PEARSON TYPE III Standard Deviation 0.217 Q2 = 6,770 Weighted Skew -0.213 Q5 = 10,200 Q10 = 12,400 Q25 = 15,400 Q50 = 17 600 Q100 = 19:800 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height , ' I year height 3 year height 3 (ft) .(ft3 /s) (ft) (ft /s) (ft) (ft /s) 1943 Jan. 21 15.66 7,210 1958 Jan. 27 15.41 7,260 1973 Apr. 4 17.40 12,400 1944 Mar. 22 17.43 12,400 1959 Apr. 15 14.75 6,400 1974 Apr. 10 13.80 4,600 1945 Sept.19 22.35 29,400 1960 Apr. 7 15.68 7,960 1975 July 16 15.99 8,980 1946 Dec. 29 14.06 3,980 1961 Feb. 27 15.90 9,320 1976 June 27 15.36 7,720 1947 Apr. 18 14.36 4,460 1962 Mar. 14 16.25 10,200 1977 Mar. 22 16.11 9,280 1948 Mar. 10 15.47 7,480 1963 Jan. 23 14.89 6,680 1978 Jan. 26 1949 Dec. 1 16.85 10,900 1964 Mar. 18 16.86 12,200 1979 Feb. 25 18.26 15,600 1950 Dec. 18 11.91 1,790 1965 Oct. 19 16.33 10,600 1980 Nov. 12 15.86 8,720 1951 Apr. 12 13.02 2,970 1966 Mar. 7 14 92 6,700 1981 Feb. 23 13.60 4,250 1952 Sept. 3 18.06 15,000 1967 Sept.12 17,400 1982 Jan. 5 15.69 8,380 1953 Feb. 19 13.86 4,350 1968 Jan. 13 15.63 8,260 1983 --- 18.36 16,000 1954 Apr. 4 14.73 5,800 1969 Apr. 22 14.35 5,700 1984 Mar. 31 15.12 7,010 1955 Apr. 17 15.40 7,720 1970 Mar. 2S 14.12 5,240 1985 Sept.19 12.17 2,230 1956 Mar. 20 14.40 5,230 1971 Mar. 6 16.28 9,700 1986 Nov. 30 14.04 5,080 1957 May. 15 13.97 4,520 1972 Apr. 4 11.79 1,860 1987 Mar. 1 12.16 2,210 1988 Oct. 29 12.38 2,450 1Estimated by hydrographic comparison with Lynches River at Effingham, station number 02132000 54 PEE DEE RIVER BASIN 02131990 CARTER CREEK AT EFFINGHAM, SC LOCATION.--Lat 34*03'51", long 79*46'03", Florence County, Hydrologic Unit 03040202, on upstream side of culvert on U.S. Highway 301, 0.8 mi. northwest of Effingham and 0.9 mi upstream from Lynches River. DRAINAGE AREA.--8.28 mi2. PERIOD OF RECORD.--December 1966 to current year. GAGE.--Dual digital water-stage and rainfall recorders, December 1966 to October 1974. Partial record crest gage, December 1974 to present. REMARKS.--Records good. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 898 ft3/s, Mar 3, 1971. STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 715 ft3/s and graphically extended on logarithmic plotting paper. FLOOD-FREQUENCY DATA (ft3 /s) LOG-PEARSON TYPE III STATISTICS (LOG UNITS) 18 YEARS OF RECORD Mean - 2.319 LOG-PEARSON TYPE III Standard Deviation - 0.282 Q 210 Weighted Skew - -0.065 Q 361 477 Q10 640 Q25 773 Q50 Q100 915 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height year height year height ft) (ft 3/a) (ft) (ft3/s) (ft) (ft3/s) 1969 Aug. 5 91.4 1975 Jan. 20 3.13 63,8 1981 July 3 5.20 222 1970 Mar. 22 274 1976 June 27 5.73 287 1982 June 5 5.20 222 1971 Mar. 3 898 1977 Mar. 22 5.33 237 1983 Mar. 24 6.48 409 1972 May. 18 176 1978 Jan. 26 5.31 235 1984 Feb. 21 3.61 96.0 1973 Feb. 2 326 1979 Mar. 24 5.73 288 1987 Mar. 7 5.97 321 1974 Aug. 5 374 1980 Mar. 13 5.17 219 1988 Mar. 11 3.74 104 55 PEE DEE RIVER BASIN 02132000 LYNCHES RIVER AT EFFINGHAM, SO (National stream-quality accounting network station) LOCATION.--Lat 34*0310511, long 79*45115", Florence County, Hydrologic Unit 03040202, on left bank at downstream side of bridge an U.S. Highway 52, 75 ft upstream from Seaboard Coast Line Railroad Bridge, 1.0 mi south of Effingham, and at mile 43.4. DRAINAGE AREA.--1,030 m12, approximately. WATER-DISCHARGE RECORDS PERIOD OF RECORD.--August 1929 to current. Gage-height records collected at same site since 1891 are contained in reports of National Weather Service. GAGE.--Water-stage recorder. Datum of &age is 58.49 ft above National Geodetic Vertical Datum of 1929. Prior to Sept. 7, 1934, nonrecording gage at same site and datum. REMARKS.--Records good. EXTREMES FOR PERIOD OF RECORD. --Maximum discharge, 25,000 ft3/s, Sept. 22, 1945, gage height, 21.21 ft. STAGE-DISCHARGE RELATION, --Defined by curzent-meter measurements below 16,900 ft3/s and graphically extended on logarithmic plotting paper. FLOOD-FREQUENCY DATA (ft3/s) LOG-PEARSON TYPE III STATISTICS (LOG UNITS) 62 YEARS OF RECORD Mean - 3.750 LOG-PEARSON TYPE III Standard Deviation - 0.254 Q2 = 5,610 Weighted Skew - 0.044 Q5 = 9,190 Q 10 = 11,900 = 15,800 Q25 = Q50 18 900 Q100 = 22:300 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height year height 3 year height 3 (ft) (ft3/s) (ft) (ft Is) (ft) (ft /8) 1892 Jan. 24 17.50 1927 Mar. 12 8.80 1962 Mar. 18 15.83 7,800 1893 Sept. 4 16.00 1928 Sept.24 19.50 16,100 1963 Jan. 27 15.01 6,400 1894 Aug. 11 16.20 1929 Mar. 10 17.50 10,800 1964 Mar. 22 15.75 7,800 1895 Oct. 15 16.50 1930 Oct. 7 19.25 15,200 1965 Oct. 22 15.87 7,940 1896 July 15 16.00 1931 Aug. 31 10.40 2,330 1966 Mar. 7 15.38 7,020 1897 Feb. 13 14.40 1932 Jan. 15 13.70 4,780 1967 Sept.16 14.08 5,570 1898 Aug. 30 13.70 1933 Oct. 24 15.30 6,830 1968 Jan. 18 14.26 5,420 1899 Feb. 12 17.20 1934 June 13 10.30 2,300 1969 Apr. 26 12.52 3,790 1900 Apr. 25 16.60 1935 Sept.14 12.58 3,750 1970 Mar. 31 12.76 3,980 1901 June 22 17.20 1936 Apr. 12 18.66 14,400 1971 Mar. 5 17.46 11,700 1902 Feb. 8 15.00 1937 May 2 14.09 5,200 1972 Jan. 18 14.21 5,360 1903 Feb. 14 16.90 1938 Aug. 2 13.72 4,880 1973 Feb. 5 16.68 9,710 1904 Aug. 14 12.80 1939 Mar. 4 17.39 11,200 1974 Aug. 15 12.18 3,550 1905 Feb. 22 13.50 1940 Aug. 18 9.43 1,98a 1975 July 20 16.69 9,740 1906 June 17 14.60 1941 July 18 12.22 3,420 1976 June 28 13.37 4,500 1907 July 5 10.00 1942 May 28 14.39 5,640 1977 Mar. 20 13.81 4,920 1908 Aug. 30 20.00 18,000 1943 Jan. 26 13.48 4,600 1978 Jan. 26 16.09 8,380 1909 June 12 12.90 1944 Mar. 26 16.42 9,050 1979 Mar. 2 17.45 11,100 1910 June 18 13.10 1945 Sept.22 21.21 25,000 1980 Apr. 3 16.69 9,380 1911 Mar. 16 9.50 1946 Jan. 2 13.10 4,200 1981 Feb. 21 10.23 2,430 1912 Feb. 21 16.50 1947 Apr. 16 13.57 4,700 1982 Jan. 10 15.28 6,850 1913 Mar. 21 25.70 1948 Feb. 16 24.67 6,180 1983 Mar. 24 17.19 10,400 1914 Mar. 6 12.80 1949 Dec. 5 15.92 8,320 1984 Apr. 5 13.54 4,670 1915 Jan. 25 13.60 1950 Dec. 24 8.43 1,630 1985 Feb. 11 11.92 3,550 1916 July 20 18.70 1951 Apr. 17 9.81 2,120 1986 Nov. 30 12.57 3,950 1917 June 18 12.00 1952 Sept. 6 16.76 10,90D 1987 Mar. 7 17.07 10,200 1918 May 18 12.00 1953 Feb. 23 12.35 3,920 1988 Jan. 28 10.02 2,410 1919 July 29 16.00 1954 Apr. 8 12.35 3,720 1920 Mar. 22 11.90 1955 Apr. 22 12.80 3,920 1921 Feb. 16 16.50 1956 Mar. 25 11.41 2,840 1922 Mar. 12 17.30 1957 May 21 10.09 2,260 1923 Mar. 24 12.60 1958 Feb. 1 13.53 5,290 1924 Apr. 13 13.40 1959 Feb. 12 12.74 3,840 1925 Jan. 21 17.30 1960 Apr. 10 16.31 8,840 1926 Apr. 18 14.30 1961 Mar. 3 15.74 7,600 56 PEE DEE RIVER BASIN 02132100 TWO MILE BRANCH NEAR LAKE CITY, SC LOCATION.--Lat 33'53138", long 79*45138", Florence County, Hydrologic Unit 03040202, at culvert on U.S. Highway 378 By-Pass, and 1.4 mi north of Lake City. DRAINAGE AREA.--19.0 m12. PERIOD OF RECORD.--October 1976 to current year. GAGE.--Crest stage partial record station. REMARKS.--Records good. EXTREMES FOR PERIOD OF RECORD. --Maximum discharge, 1,200 ft3/s, Mar. 13, 1980, gage height, 7.31 ft. STAGE-DISCHARGE RELATION. --Defined by current-metex measurements below 480 ft3/s and graphically extended on logarithmic plotting paper. FLOOD-FREQUENCY DATA (ft3 ,/a) &PEARSON TYPE III STATISTICS (LOG UNITS) 13 YEARS OF RECORD T_ - 2.388 LOG-PEARSOK TYPE III Standard Deviation = 0.276 Q2 = 236 Weighted Skew - 0.334 Q5 = 412 Q 10 = 563 Q25 - 798 Q50 1,010 Q100 1,250 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height 3 year height 3 year height 3 (ft) (ft /a) (ft) (ft /a) (ft) (ft /a) 1976 June 28 5.15 210 1981 July 3 4.46 102 1986 Nov. 30 4.37 95 1977 Mar. 20 4.87 156 1982 Jan. 10 5.46 285 1987 Sept.10 5.67 346 1978 Jan. 26 5.48 290 1983 July 10 5.73 364 1988 Mar. 11 5.43 278 1979 Feb. 24 5.31 248 1984 Mar. 31 5.01 182 1980 Mar. 13 7.31 1,200 1985 Aug. 18 5.21 222 57 PEE DEE RIVER BASIN 02132500 LITTLE PEE DEE RIVER NEAR DILLON, SC LOCATION.--Lat 34*2411711, long 79*20'25", Dillon County, Hydrologic Unit 03040204, near center of span on downstream side of bridge on State Highway 9, 1.9 mi southeast of Dillon, 3.9 mi (revised) upstream from Maple Swamp, and at mile 88.3. DRAINAGE AREA.--524 m12. PERIOD OF RECORD.--March 1939 to current year. GAGE.--Water-stage recorder prior to Sept. 1971, crest-stage gage thereafter. Datum of gage is 75.14 ft National Geodetic Vertical Datum of 1929 (Levels by South Carolina Highway Department). Prior to July 31, 1967, nonrecording gage and crest-stage gage at same site and datum. REMARKS.--Records good. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 9,810 ft3/s, Sept. 20, 1945, gage height, 14.64 ft. STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 6050 ft3/s and graphically extended on logarithmic platting papaer. FLOO@XOUERCY DATA (fts/s) LOG-PEARSON TYPE III STATISTICS (LOG UNITS) 49 Y F ECORD Mean - 3.404 LOG-PEARSON TYPE III Standard Deviation - 0.223 Q2 = 2,490 Weighted Skew - 0.203 Q5 = 3,880 Q = 41950 Q25 6,450 Q50 7,690 Q100 9,030 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height year height year height (ft) (ft3 /s) (ft) (ft3/s) (ft) (ft3/s) 1940 Feb. 13 8.45 1,080 1960 Oct. 17 11.42 4,650 1980 Mar. 13 9.69 2,320 1941 July 19 9.60 2,130 1961 Mar. 1 9.65 2,240 1981 Aug. 11 8.74 1,300 1942 Mar. 13 10.12 2,770 1962 Feb. 26 9.71 2,350 1982 Jan. 5 10.51 3,300 1943 July 12 9.46 2,020 1963 Jan. 23 10.73 3,440 1983 Apr. 10 12.38 6,130 1944 Mar. 25 9.55 2,130 1964 Feb. 22 10.44 3,050 1984 Apr. 5 10.43 3,210 1945 Sept.20 14.64 9,810 1965 Oct. 7 12.26 5,500 1985 Sept.19 9.98 2,660 1946 Jan. 3 9.40 2,020 1966 June 12 12.07 5,220 1986 Nov. 30 9.69 2,320 1947 Apr. 22 9.78 2,470 1967 Aug. 27 8.80 1,370 1987 Feb. 28 11.50 4,710 1948 Feb. 15 10.79 3,750 1968 Jan. 14 9.72 2,250 1988 Jan. 28 8.51 1,220 1949 Nov. 30 10.47 3,330 1969 Aug, 5 10.31 2,890 1950 Nov. 7 8.06 915 1970 Mar. 24 9.60 2,200 1951 Apr. 11 8.52 1,200 1971 Mar. 5 12.20 5,820 1952 Sept. 6 8.87 1,540 1972 May 20 8.56 1,150 1953 May 9 9.58 2,240 1973 Feb. 19 12.54 5,960 1954 Apr. 13 9.01 1,630 1974 Aug. 12 9.90 2,560 1955 Apr. 17 10.66 3,240 1975 Feb. 18 10.65 3,500 1956 Feb. 9 9.22 1,820 1976 Feb. 4 8.93 1,500 1957 June 12 1,200 1977 Jan. 10 9.82 2,460 1958 Dec. 1 10.32 3,090 1978 Jan. 30 9.76 2,400 1959 Apr. 17 10.04 2,710 1979 Feb. 24 10.49 3,290 58 PEE DEE RIVER BASIN 02135000 LITTLE PEE DEE RIVER AT GALIVANTS FERRY, SC LOCATION.--Lat 34*03'25", long 79*14'5011, Horry-Marion County Line, Hydrologic Unit 03040204, near left bank on downstream side of bridge on U.S. Highway 501, at Galivants Ferry, 1.0 mi downstream from Lake Swamp, and at mile 41.7. DRAINAGE AREA.--2,790 m12, approximately. PERIOD OF RECORD.--October 1941 to current year. Monthly discharge only for some periods, published in WSP 1303. GAGE.--Water-stage recorder and data collection platform. Datum of gage is 23.95 ft above National Geodetic Vertical Datum of 1929. Prior to July 26, 1967, nonrecording gage and crest-stage gage at same site and datum. REMARKS.--Records good. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 27,600 ft3/s, Oct. 9, 10, 1964, gage height, 13.01 ft. EXTREMES OUTSIDE PERIOD OF RECORD.--Maximum stage known, 16.0 ft, in September 1928, from floodmark set by local resident. STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 26,100 fts/s and graphically extended on logarithmic plotting paper. FLOOD-FREQUENCY DATA (ft3 /s) LOG-PEARSON TYPE III STATISTICS (LOG UNITS) 47 YEARS OF RECORD Mean - 4.079 LOG-PEARSON TYPE III Standard Deviation = 0.195 Q2 = 12,100 Weighted Skew = -0.171 Q5 = 17,600 Q10 21,100 Q25 25,600 Q50 28,900 Q100 32,200 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height year height year height (ft) (ft 3 /s) (ft) (ft3 /a) (ft) (ft3 /a) 1928 Sept.-- 16.00 1961 Apr. 18 10.09 12,500 1981 Aug. 23 10.67 11,400 1942 Mar. 14 9.87 11,000 1962 Mar. 18 9.95 11,100 1982 Feb. 20 10.87 11,400 1943 July 18 9.76 10,500 1963 Jan. 27 10.57 15,200 1983 Mar. 22 12.72 24,400 1944 Feb. 24 9.95 11,500 1964 Sept.17 10.30 13,400 1984 Apr. 5 10.44 10,500 1945 Sept.23 13.23 26,800 1965 Oct. 9 13.01 27,600 1985 Feb. 15 9.45 6,750 1946 Jan. 2 10.74 15,200 1966 Mar. 11 10.68 15,300 1986 Dec. 13 8.75 5,010 1947 Apr. 20 9.69 10,600 1967 Feb. 20 8.66 6,090 1987 Mar. 6 11.94 18,200 1948 Feb. 18 11.24 17,600 1968 Jan. 19 9.64 10,300 1988 Jan. 8 8.77 6,110 1949 Dec. 4 10.62 14,800 1969 Aug. 10 11.07 17,200 1950 July 18 8.08 4,310 1970 Mar. 27 9.71 10,600 1951 Apr. 16 8.32 4,890 1971 Mar. 8 12.29 25,000 1952 Apr. 2 8.82 6,690 1972 Feb. 8 10.02 12,000 1953 Mar. 19 9.47 9,730 1973 Apr. 10 11.86 22,100 1954 Apr. 15 9.10 7,930 1974 Aug. 12 11.79 21,600 1955 Sept.11 10.36 13,900 1975 Feb. 26 11.13 13,000 1956 Feb. 14 9.48 9,270 1976 Feb. 4 9.91 8,030 1957 Feb. 13 8.98 7,510 1977 Mar. 28 10.69 10,900 1958 Apr. 7 10.00 12,000 1978 June 15 11.27 12,200 1959 Mar. 10 11.21 17,600 1979 Sept.11 12.51 20,200 1960 Aug. 2 10.66 14,800 1980 Apr. 1 11.60 l4t800 59 PEE DEE RIVER BASIN 02135300 SCAPE ORE SWAMP NEAR BISHOPVILLE, SC LOCATION.--Lat 34*09102", long 80*18'18", Lee County, Hydrologic Unit 03040205, at bridge on U.S. Highway 15, 0.1 mi downstream from Beaverdam Creek, 0.9 mi upstream from Seaboard Coast Line Railroad bridge, and 5.8 mi southwest of Bishopville. DRAINAGE AREA.--96.0 m12. PERIOD OF RECORD.--July 1968 to current year. GAGE.--Water-stage recorder. Datum of gage is 164.53 ft above National Geodetic Vertical Datum of 1929. REMARKS.--Records good. EXTREMES FOR PERIOD OF RECORD. --Maxirm,m discharge 1,700 ft3/s, Sept. 7, 1979, gage height, 8.54 ft. STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 1,330 fts/s and graphically extended on logarithmic plotting paper. FLOOD-FREQUENCY DATA (ft3 /a) LOG-PEARSON TYPE III STATISTICS (LOG UNITS1 20 YEARS OF RECORD Mean . 2.828 LOG-PEARSON TYPE III Standard Deviation - 0.203 Q2 = 676 Weighted Skew - -0.050 Q5 = 999 Q10 = 1,220 Q 25 = 11510 1,740 Q50 = 1,960 Q100 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height 3 year height 3 year height 3 (ft) (ft /a) (ft) (ft /a) (ft) (ft /a) 1969 Feb.19 6.90 630 1976 June 20 6.60 490 1983 Mar. 19 7.82 1,150 1970 Mar.24 6.78 570 1977 Dec. 18 6.57 478 1984 May. 31 5.95 662 1971 Mar. 5 8.09 1,330 1978 Apr. 28 7.02 702 1985 Aug. 19 6.59 486 1972 Jan.15 7.14 764 1979 Sept. 7 8.54 1,700 1986 Aug. 22 6.83 574 1973 7.28 848 1980 Mar. 31 6.99 684 1987 Mar. 3 7.27 786 1974 Feb.19 6.07 273 1981 Feb. 13 5.96 278 1988 Aug. 30 7.90 1,180 1975 Apr. 5 7.26 846 1982 Jan. 4 6.61 494 60 PEE DEE RIVER BASIN 02135500 BLACK RIVER NEAR GABLE, SC LOCATION.--Lat 33'54100", long 80'09'55", Sumter County, Hydrologic Unit 03040205, near left bank on downstream side of McBride Crossing on U.S. Highway 378, 1.0 mi downstream from Church Branch, 6.3 mi northwest of Gable, and at mile 123.1. DRAINAGE AREA.--401 m12. PERIOD OF RECORD.--June 1951 to June 1966, April 1972 to current year. GAGE.--Water-stage recorder. Elevation of gage is 95 ft above National Geodetic Vertical Datum of 1929, (from topographic map). Crest-stage station Oct. 1970 to Sept. 1971 at same site and datum. Prior to Dec. 9, 1955, wire-weight gage at same site and datum. REMARKS.--Records good. EXTREMES FOR PERIOD OF RECORD. --Maximum discharge, 12,500 ft3/s, Mar. 5, 1971, gage height, 6.82 ft; maximum gage height 6.92 ft, June 13, 1973. STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 7,970 fts/s and graphically extended on logarithmic plotting paper. FLOOD-FREQUENCY DATA (ft3 /s) LOG-PEARSON TYPE III STATISTICS (LOG UNITS) 32 YEARS OF RECORD Mean . 3.421 LOG-PEARSON TYPE III Standard Deviation - 0.288 Q2 = 2,770 Weighted Skew - -0.434 Q 5 = 41650 Q10 = 5,950 Q = 7,590 Q 25 = 8 790 50 = 9:970 Q100 Peak Stages and Discharges I Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height 3 year height (ft3 year height 3 (ft) (ft Is) (ft) /a) (ft) (ft /a) 1952 Sept. 3 5.22 4,150 1962 Feb. 25 4.33 2,340 1977 Dec. 16 4.46 1,840 1953 Feb. 28 3.95 1,660 1963 Jan. 23 4.45 2,520 1978 Jan. 28 4.56 2,080 1954 Dec. 17 3.30 742 1964 Sept. 1 5.80 6,650 1979 Sept. 7 5.68 4,320 1955 Apr. 18 3.26 518 1965 June 16 6.10 8,300 1980 Mar. 31 4.98 2,760 1956 Feb. 9 3.58 835 1966 Mar. 6 5.13 3,830 1981 July 4 5.03 2,860 1957 Mar. 28 3.77 713 11971 Mar. 5 6.82 12,500 1982 Feb. 19 4.60 2,200 1958 Apr. 17 5.16 3,780 1973 June 13 6.92 7,900 1983 Mar. 19 5.92 4,950 2959 Mar. 8 4.44 2,320 1974 Aug. 6 4.79 2,540 1984 July 24 4.79 2,560 1960 Apr. 7 5.15 3,780 1975 Feb. 21 5.09 2,880 1985 Aug. 19 4.71 2,420 1961 Aug. 6 5.08 3,670 1976 June 20 5.12 3,060 1986 Nov. 23 5.97 5,080 1987 Mar. 2 5.21 3,370 1988 Sept. 3 4.24 1,750 1 Stage-discharge relation altered by bridge construction. 61 PEE DEE RIVER BASIN 02136000 BLACK RIVER AT KINGSTREE, SC LOCATION.--Lat 33*3914011, long 79*50'10", Williamsburg County, Hydrologic Unit 03040205, on left bank at downstream side of bridge on U.S. Highway 52 at Kingstree, 1.0 mi downstream from Kingstree Swamp Canal, and at mile 86.7. DRAINAGE AREA.--1,252 m12. PERIOD OF RECORD.--August 1929 to current year. Gage-height records collected at same site since 1894 are contained in reports of National Weather Service. REVISED RECORDS.--WSP 1032: 1928(m), drainage area WSP 1333: 1930(m), 1931, 1936. GAGE.--Datum of gage is 25.66 ft above National Geodetic Vertical Datum of 1929. Prior to Nov. 7, 1934, nonrecording gage at same site and datum. REMARKS.--Records good. EXTREMES FOR PERIOD OF RECORD. --Maximum discharge, 58,000 ft3/s, June 14, 1973, gage height, 19.77 ft. STAGE-DISCHARGE RELATION. --Defined by current-meter measurement's below 44,300 ft3/a and graphically extended on logarithmic plotting paper. FLOOD UENCY DATA (ft3/s) STATISTICS (LOG UNITS) YEXQ 61 OF RECORD Mean - 3.853 1GRAPHICAL SOLUTI5N_ Standard Deviation - 0.276 Q2 = 5,700 2Station Skew - 2.365 Q5 = 10,500 Q10 = 16,000 Q25 = 32,500 Q50 = 52,500 Q100 = 80,000 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height year height year height (ft) (ft3 /3) (ft) (ft3 /a) (ft) (ft3/a) 1893 Sept.11 14.50 1928 Sept.21 18.00 41,600 1963 Jan. 27 11.67 4,920 1894 Aug. 9 12.50 1929 Feb. 22 11.70 6,060 1964 Sept. 5 12.52 7,310 1895 Feb. 5 11.60 1930 Jan. 25 12.20 7,760 1965 Oct. 7 14.73 17,900 1896 Feb. 14 10.70 1931 Jan. 20 10.10 3,120 1966 Mar. 8 13.00 9,240 1897 Feb. 15 10.30 1932 Mar. 16 8.60 1,550 1967 Jan. 13 9.08 1,680 1898 Sept. 7 9.90 1933 Feb. 19 11.20 4,600 1968 June 17 10.45 3,080 1899 Feb. 21 11.60 1934 June 12 6.80 908 1969 May 26 11.53 4,690 1900 Apr. 26 11.90 1935 Sept.17 9.83 2,510 1970 Mar. 28 12.42 6,520 1901 June 1 12.00 1936 Apr. 13 13.07 11,800 1971 Mar. 7 15.22 23,600 1902 Mar. 5 10.10 1937 Feb. 4 11.53 5,440 1972 Feb. 7 12.50 7,120 1903 June 16 11.80 1938 Apr. 14 12.00 6,730 1973 June 14 19.77 58,000 1904 Feb. 28 10.00 1939 Mar. 4 13.21 12,200 1974 Feb. 22 11.22 3,860 1905 May 9 10.90 1940 Feb. 23 9.70 2,400 1975 Feb. 25 12.42 7,120 1906 June 22 11.80 1941 July 24 11.32 5,000 1976 July 9 12.24 6,490 1907 Oct. 27 10.10 1942 Mar. 9 12.26 8,160 1977 Mar. 18 11.43 4,260 1908 May 3 10.40 1943 Mar, 29 10.44 3,310 1978 Jan. 29 12.16 6,230 1909 July 17 9.40 1944 Mar. 27 11.93 6,680 1979 Sept.11 12.88 8,880 1910 June 22 11.40 1945 Sept.20 16.07 29,100 1980 Mar. 23 12.68 8,060 1911 Oct. 22 8.20 1946 Jan. 2 11.62 5,780 1981 July 12 9.09 1,520 1912 Jan. 12 13.30 1947 Apr. 19 12.22 7,760 1982 Jan. 7 11.30 4,250 1913 Mar. 19 12.90 1948 Feb. 14 12.81 10,400 1983 Mar. 21 14.05 15,200 1914 Mar. 9 11.20 1949 Dec. 2 12.50 9,020 1984 Aug. 1 12.99 9,350 1915 May 16 12.70 1950 Sept.12 9.78 2,510 1985 Feb. 14 10.50 2,940 1916 July 17 15.50 1951 Apr. 9 9.63 2,300 1986 Nov. 28 12.59 7,720 1917 Jan. 30 10.90 1952 Sept. 7 11.61 5,780 1987 Mar. 5 12.92 9,050 1918 May 19 12.00 1953 Mar. 3 11.44 5,240 1988 Mar. 16 10.38 2,710 1919 July 28 12.50 1954 Jan. 4 9.09 1,860 1920 Apr. 7 10.90 1955 Sept. 9 10.79 3,900 1921 May 22 11.10 1956 Mar. 5 9.96 2,670 1922 Mar. 14 12.70 1957 Mar. 29 8.92 1,590 1923 Oct. 25 10.20 1958 Apr. 19 13.54 11,800 1924 July 6 14.60 1959 Mar. 9 13.58 12,000 1925 Jan. 21 15.20 1960 Dec. 22 12.65 7,420 1926 Feb. 10 9.90 1961 Apr. 18 12.97 9,020 1927 Aug. 19 10.50 1962 Mar. 1 11.70 5,020 iThe frequency relation for this stream had a sharp break at about 10-year recurrence interval where storage effect is reduced by water reaching the banks ot the overflow section. This is verified by the station rating; therefore, the flood frequency was determined graphically. 2Station skew computed using graphical frequency relation. 62 SANTEE RIVER BASIN 02146000 CATAWBA RIVER NEAR ROCK HILL, SC LOCATION.--Lat 34*59'05", long 80'58'27", York County, Hydrologic Unit 03050103, on right bank, at downstream side of bridge on U.S. Highway 21, 3.5 mi downstream from Lake Wylie Dam, 5.0 mi northeast of Rock Hill, 7.5 mi upstream from Sugar Creek, and at mile 137.6. DRAINAGE AREA.--3,050 m12, approximately. PERIOD OF RECORD.--September 1895 to September 1903, April 1942 to current year. Monthly discharge only for some periods, published in WSP 1303. REVISED RECORDS.--WSP 1303: 1895-1903, WSP 1333: 1942-43(M), 1953(M). WSP 1623: 1942-51 (yearly runoff). GAGE.--Water-stage recorder. Datum of gage is 485.82 ft above National Geodetic Vertical Datum of 1929. Sept. 23, 1895, to July 31, 1903, nonrecording gage at Southern Railway bridge, 2.0 mi downstream, at different datum. REMARKS. --Records good. Flow regulated by Lake Wylie, usable capacity, 2,520,500,000 ftS and other power plants above station. EXTREMES FOR PERIOD OF RECORD. --Maximurn discharge, 151,000 ft3/s, May 23, 1901, gage height, 24.15 ft, site and datum then in use. STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 78,000 fts/s and graphically extended on logarithmic plotting paper. Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height 3 year height 3 year height 3 ft) (ft /a) (ft) (ft /s) (ft) (ft /a) 1896 July 10 15.20 71,500 1954 Jan. 23 16.01 51,000 1974 Apr. 6 10.31 25,200 1897 Feb. 7 14.80 68,500 1955 Apr. 15 7.69 14,200 1975 Mar. 15 17.57 62,400 1898 9.00 30,600 1956 Apr. 16 7.77 14,600 1976 Mar. 8 7.47 13,400 1899 Mar. 20 18.00 95,000 1957 Apr. 7 12.93 36,100 1977 Oct. 9 16.57 55,400 1900 12.30 50,000 1958 Apr. 28 15.82 50,OQO 1978 Nov. 7 13.44 39,000 1901 May 23 24.15 151,000 1959 Dec. 30 10.39 25,100 1979 Feb. 25 13.86 43,300 1902 Dec. 30 19.70 108,000 1960 Feb. 6 15.80 50,000 1980 Apr. 17 9.40 21,100 1903 Mar. 24 18.00 93,800 1961 Feb. 25 9.49 21,300 1981 Jan. 5 7.47 13,300 1942 Sept. 8 10.61 25,900 1962 Jan. 7 15.70 49,500 1982 Jan. 4 11.31 30,400 1943 July 10 16.99 56,100 1963 Mar. 6 10.73 26,300 1983 Apr. 10 10.86 28,100 1944 Sept.30 11.55 30,200 1964 Apr. 8 13.25 37,500 1984 Apr. 10 11.79 32,900 1945 Sept.19 20.84 76,800 1965 Oct. 17 14.64 44,700 1985 Feb. 2 7.55 13,600 1946 Feb. 11 15.05 46,000 1966 Mar. 5 7.66 15,000 1986 Nov. 22 10.72 27,500 1947 Jan. 20 13.57 39,300 1967 Aug. 23 13.53 39,200 1987 Mar. 1 12.06 34,300 1948 Mar. 31 13.63 39,300 1968 Jan. 11 7.74 15,000 1988 Feb. 17 7.52 13,500 1949 Nov. 28 17.79 60,200 1969 Feb. 3 7.72 14t9OO 1950 Nov. 1 10.03 23,600 1970 Aug. 13 7.84 15,400 1951 Jan. 23 7.49 13,600 1971 May 16 11.75 31,000 1952 Mar. 4 16.96 56,100 1972 June 23 10.01 24,000 1953 Mar. 24 13.49 38,900 1973 May 30 12.44 33,800 63 SANTEE RIVER BASIN 02147000 CATAWBA RIVER NEAR CATAWBA, SC LOCATION.--Lat 34*5110911, long 80'52'06", York County, Hydrologic Unit 03050103, on right bank, 60 ft downstream from Seaboard Coast Line Railroad bridge, 2CO ft downstream from Twelvemile Creek, 2.5 mi east of Catawba, and at mile 122.8. DRAINAGE AREA.--3,530 m12, approximately. PERIOD OF RECORD.--October 1968 to current year. Annual peak stages from June 1906 to December 1948. GAGE.--Water-stage recorder and data collection platform. Datum of gage is 446.18 ft above National Geodetic Vertical Datum of 1929 (levels by Bowaters Carolina Corporation). June 1906 to Dec. 21, 1948, nonrecording gage at site 2.1 mi downstream at different datum. REMARKS. --Records good. Flow regulated by Lake Wylie, usable capacity, 2,520,500,000 ft3 and other powerplants above the station. EXTREMES FOR PERIOD OF RECORD. --Maximum discharge, 73,600 ft3/s, Oct. 9, 1976, gage height, 23.81 ft. EXTREMES FOR OUTSIDE PERIOD OF RECORD.--Maximum stage known since June 1906, 40.4 ft, July 16, 1916 at site and datum then in use, from records furnished by the National Weather Service. STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 63,300 ft3/s and graphically extended on logarithmic plotting paper. Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height 3 year height 3 year height 3 (ft) (ft Is) (ft) (ft /5) (ft) (ft /8) 21901 May 23 124.80 1976 Dec. 31 8.48 15,700 1987 Mar. 1 21.10 59,200 1949 Nov.29 19.00 1977 Oct. 9 23.81 73,600 1988 Dec.28 9.23 17,900 1968 Jan.11 11.92 23,000 1978 Jan. 26 18.12 47,500 1969 Feb. 3 9.79 18,100 1979 Feb. 25 19.16 51,700 1970 Aug.13 10.22 19,200 1980 Mar. 29 14.00 32,300 1971 May 16 14.01 28,500 1981 Feb. 19 8.08 14,400 1972 Oct.17 12.15 23,900 1983 Apr. 10 13.40 30,700 1973 Apr. 1 17.16 37,500 1984 Dec. 12 15.05 36,300 1974 Apr. 6 13.43 27,100 1985 Feb. 2 11.74 25.400 1975 Mar.15 21.75 63,400 1986 Nov. 22 15.80 39,000 lFrom information by U.S. Weather Bureau. 2No record Jan I to Jun 30. 64 SANTEE RIVER BASIN 02147500 ROCKY CREEK AT GREAT FALLS, SC LOCATION.--Lat 34*3314511, long 80*55,00". Chester County. Hydrologic Unit 03050103, on left bank, 350 ft downstream from Turkey Branch, 1.0 mi west of Great Falls, and at mile 1.8. DRAINAGE AREA.--194 mi2. PERIOD OF RECORD.--February 1951 to September 1981, August 1986 to current year. GAGE.--Water-stage recorder. Altitude of gage is 299 ft above National Geodetic Vertical Datum of 1929, (by barometer). REMARKS.--Records good. - EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 31,300 ft3/s, Aug. 23, 1967, gage height, 18.82 ft. STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 21,000 fts/s and graphically extended on logarithmic plotting paper. FLOOD-FREQUENCY DATA (fts /a) LOG-PEARSON TYPE III STATISTICS (LOG UNITS) 32 YEARS OF RECORD Mean - 3.849 LOG-PEARSON TYPE III Standard Deviation - 0.204 QQ2 - 6,750 Weighted Skew - 0.570 5 - 10,300 Q10 - 13,100 Q - 17 400 Q25 _ 21:200 50 - 25,400 Q100 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height 3 year height year height (ft) (ft /a) (ft) (ft3/3) (ft) (ft 3 /a) 1952 Mar. 4 9.77 8,880 1962 Jan. 7 8.86 7,570 1972 Jan. 11 7.36 5,110 1953 Feb. 21 7.71 5,230 1963 Mar. 13 8.43 6,510 1973 Apr. 1 12.92 16,600 1954 Jan. 17 8.08 5,860 1964 Mar. 15 9.29 8,490 1974 Oct. 2 6.66 3,500 1955 Apr. 15 8.27 6,180 1965 Oct. 16 10.95 13,000 1975 Mar. 14 9.21 8,470 1956 Mar. 17 7.56 5,080 1966 Mar. 5 8.38 6,470 1976 Mar. 17 6.43 3,650 1957 Apr. 6 7.04 4,290 1967 Aug. 23 18.82 31,300 1977 Jan. 10 7.35 5,100 1958 Jan. 25 7.93 5,600 1968 July 10 9.53 9,110 1978 Oct. 26 11.62 13t3OO 1959 Sept.30 10.23 10,800 1969 Apr. 19 9.94 9,930 1979 Feb. 24 7.78 5,790 1960 Feb. 14 8.70 6,910 1970 Mar. 22 6.67 4,000 1980 Mar. 9 7.63 8,230 1961 Feb. 25 8.83 7,340 1971 Mar. 4 8.41 6,900 1981 Feb. 12 7.57 5,420 1987 Mar. 1 8.64 7,320 1988 Nov. 28 4.86 1,790 65 SANTEE RIVER BASIN 02147600 SCABBER BRANCH NEAR GREAT FALLS, SC LOCATION.--Lat 34*30117", long 81*00'22", Fairfield County, Hydrologic Unit 03050104, on the upstream side of box culvert on State Highway 200, 1.1 mi upstream of Big Wateree Creek and 7.0 mi southwest of Great Falls. DRAINAGE AREA.--4.55 m12. PERIOD OF RECORD.--Kovember 1974 to current year. GAGE.--Dual digital water-stage and rainfall recorders, December 1966 to October 1974. Partial record crest stage, November 1974 to current year. REMARKS.--Records good. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 2,670 ft3js' October 26, 1978, &age height 10.07 ft. STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 100 fts/s and extended by indirect methods for computing peak discharge at culverts. FLOOD-FREQUENCY DATA (ft3/3) LOG-PEARSON TYPE III STATISTICS (LOG UNITS) 10 YEARS OF RECORD Mean - 3.070 LOG-PEARSON TYPE III Standard Deviation = 0.245 Q2 = 1,150 Weighted Skew = 0.178 Q = 11880 = 2,440 Q10 3,260 Q 5 = Q50 = 3,940 Q100 = 4,690 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height year height year height (ft) (ft 3/s) (ft) (ft3/a) (ft) (ft3 /s) 1977 Mar. 31 6.17 1,110 1983 July 5 6.15 1,100 1988 1978 Oct. 26 10.07 2,670 1984 Max. 6 5.51 878 1979 Apr. 26 5.78 973 im Aug. 17 8.82 2,168 1981 Feb. 11 5.59 906 19a6 Aug. 18 9.95 2,620 1982 Apr. 26 4.86 651 1987 Jan. 19 4.48 534 66 SANTEE RIVER BASIN 02148000 WATEREE RIVER NEAR CAMDEN, SC LOCATION.--Lat 34-14'4011, long 80'39'15'', Kershaw County, Hydrologic Unit 03050104, in pier of downstream bridge on U.S. Highway 1, 1,500 ft downstream from Five and Twenty Creek, 4,000 ft upstream from Seaboard Coast Line Railroad bridge, 2.2 mi west of Camden, 7.4 mi downstream from Wateree Dam, and at mile 68.8. DRAINAGE AREA. --5,070 m12, approximately. PERIOD OF RECORD.--January to December 1903 (gage heights only), October 1904 to September 1910, October 1929 to current year. Monthly discharge only for some periods, published in WSP 1303. Gage-height records collected at site 1.5 mi downstream 1891-1934, at site 830 ft upstream January 1935 to September 1942, and at present site since October 1942, are contained in reports of National Weather Service. REVISED RECORDS.--WSP 802: 1930. WSP 952: Drainage area. WSP 1082: 1934(M). WSP 1433: 1905-10. WSP 1623: 1930-51 (monthly and yearly runoff). GAGE.--Water-stage recorder and data collection platform. Datum of gage is 119.36 ft above National Geodetic Vertical Datum of 1929. January 1903 to September 1910, nonrecording gage at site 1.5 mi downstream at datum 1.65 ft lower. Oct. 1, 1929 to Sept. 1, 1942, recording gage at site 830 ft upstream at same datum. REMARKS.--Records good. Flow regulated by powerplant at Wateree Reservoir (usable capacity, 2,794,000,000 fts) and by other powerplants above station. EXTREMES FOR PERIOD OF RECORD. --Maximum discharge, 366,000 fts/s, Aug. 26, 1908 gage height, 39.7 ft, site and, datum then in use, from records of National Weather Service, from Sating curve extended above 122,000 ft Is on basis of computation, by Duke Power Co., of peak flow 382,000 ft /a over dam at Rocky Creek Reservoir. EXTREMES FOR OUTSIDE PERIOD OF RECORD.--The flood of July 18, 1916 reached a stage of 40.4 ft, datum 117.71 ft above mean sea level, at site 1.5 mi downstream, from reco s of National Weather Service, discharge, 400,000 ft3 q Is, from rating curve extended above 122,000 ft Is, as explained above. STAGE-DISCHARGE RELATION. --Defined by current-metex measurements below 102,000 ft3/s at current site and graphically extended on logarithmic plotting paper. Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height 3 year height 3 year height 3 (ft) (ft /a) (ft) (ft Is) (ft) (ft /a) 1886 Sept.-- 31.50 1924 July 9 24.50 1957 Apr. 10 19.63 22,200 1892 Jan. 20 30.10 1925 Jan. 20 31.00 1958 Nov. 26 25.20 36,800 1893 Aug. 30 29.60 1926 Apr. 2 19.40 1959 July 11 17.45 18,300 1894 Oct. 24 30.50 1927 July 23 12.70 1960 Apr. 6 28.54 58,800 1895 Oct. 10 30.20 1928 Aug. 18 35.00 1961 Feb. 26 27.00 46,8DO 1896 July 11 28.80 1929 Mar. 1 31.80 1962 Jan. 8 22.87 30,000 1897 Feb. 8 29.70 1930 Oct. 3 36.20 163,000 1963 Mar. 15 20,100 1898 Sept.25 28.00 1931 Dec. 23 14.31 11,600 1964 Apr. 9 26.50 43,900 1899 Feb. 8 31.00 1932 Jan. 9 28.31 50,700 1965 Oct. 18 29.07 64,500 1900 Apr. 23 28.40 1933 Dec. 28 25.37 32,000 1966 Mar. 6 18.99 21,100 1901 May 24 32.50 1934 June 9 20.65 20,200 1967 Aug. 25 32.22 88,300 1902 Dec. 31 31.20 1935 Mar. 14 24.03 30,000 1968 Jan. 12 20.91 24,900 1903 Mar. 25 30.40 1936 Apr. 7 36.63 168,000 1969 Apr. 20 21.41 26,000 1904 Aug. 9 25.20 1937 Jan. 4 27.26 52,500 1970 Mar. 23 16.83 17,800 1905 July 15 29.60 66,800 1938 Apr. 9 14.92 13,300 1971 Mar. 5 23.46 31,300 1906 Dec. 22 28.60 54,100 1939 Mar. 2 29.01 70,500 1972 Jan. 14 19.70 22,400 1907 Oct. 21 28.70 55,000 1940 Aug. 16 30.50 89,000 1973 Apr. 2 28.53 56,100 1908 Aug. 26 39.70 366,000 1941 July 9 28.10 60,600 1974 Apr. 7 16.00 16,700 1909 June 5 31.70 103,000 1942 Mar. 10 24.85 35,400 1975 Mar. 16 30.55 70o2OO 1910 Mar. 2 26.90 39,700 1943 Jan. 20 24.76 35,400 1976 Mar. 17 16.44 17,300 1911 Oct. 10 26.90 1944 Mar. 21 29.08 71,700 1977 Oct. 11 28.36 55,100 1912 Mar. 17 35.40 1945 Sept.19 33.84 132,000 1978 Jan. 27 26.22 42,300 1913 Mar. 17 34.00 1946 Jan. 9 24.28 33,800 1979 Feb. 26 29.17 60,200 1914 Jan. 4 27.60 1947 Jan. 21 27.87 58,500 1980 Mar. 30 25.80 40,200 1915 Dec. 27 30.50 1948 Apr. 2 27.96 59,500 1981 Feb. 13 15.41 16,500 1916 July 18 40.40 400,000 1949 Nov. 30 31.44 101,000 1982 Jan. 5 25.99 41,200 1917 Mar. 6 30.30 1950 Nov. 3 19.21 20,500 1983 Mar. 19 23.16 30,500 1918 Apr. 21 28.20 1951 Apr. 11 15.11 15,200 1984 Feb. 16 21.62 26,500 1919 July 21 33.00 1952 Mar. 5 31.35 82,900 1985 Feb. 7 15.68 16,800 1920 Aug. 29 28.60 1953 Feb. 24 20.82 24,500 1986 Nov. 24 16.13 17,400 1921 Feb. 11 31.00 1954 Jan. 24 29.36 67,000 1987 Mar. 2 30.44 69,600 1922 Feb. 16 30.20 1955 Apr. 16 22.66 30,800 1988 Jan. 21 12.69 13,700 1923 Mar. 18 30.00 1956 Mar. 18 15.93 16,800 67 SANTEE RIVER BASIN 02148300 COLONELS CREEK NEAR LEESBURG, SC LOCATION.--Lat 34*00'25", Long 80*43'58", Richand County, Hydrologic Unit 03050104, at bridge on State Highway 262, 0.2 mi above Jumping Run Creek, 1.9 mi southwest of Leesburg, and at mile 8.0. DRAINAGE AREA.--38.1 m12. PERIOD OF RECORD.--September 1966 to September 1980. GAGE.--Water-stage recorder. Datum of gage is 157.97 ft above National Geodetic Vertical Datum of 1929. REMARKS.--Records good. EXTREMES FOR PERIOD OF RECORD. --Maximum discharge, 494 fts/s, June 10, 1973, gage height, 5.28 ft. STAGE-DISCHARGE RELATION. --Defined by curzent-meter measurements below 350 ft3/s and graphically extended on logarithmic plotting paper. FLOOD-FREQUENCY DAT&-Cft3/s) LOG-PEARSON TYPE III STATISTICS (LOG UNITS) 14 YEARS OF RECORD Mean = 2.464 LOG-PEARSON TYPE III Standard Deviation - 0.248 Q2 = 280 Weighted Skew - 0.395 Q5 = 464 Q10 = 617 = 850 Q25 = - Q 1 060 50 = 1:290 Q100 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height 3 year height 3 year h7i,11 (ft3/.) (ft) (ft /s) (ft) (ft /a) ft) 1967 Aug. 11 7.78 1--- 1972 Jan. 14 4.28 216 1977 Dec. 12 4.56 285 1968 Jan, 11 4.07 173 1973 Junb-10 5.28 494 1978 Jan. 26 4.07 174 1969 Oct. 20 4.13 273 1974 Jan. 2 4.17 194 1979 Sept. 5 5.27 491 1970 Mar. 22 4.13 186 1975 Apr. -3 4.28 216 1980 Nov. 3 4.46 257 1971 Mar. 3 5.06 428 1976 July 6 4.30 220 1Discharge published in WRI 82-1 of 1350 ft3/s was determined by a stage-discharge rating exceeding 300 percent and may be unreliable. 68 SANTEE RIVER RASIN 02153500 BROAD RIVER NEAR GAFFNEY, SC LOCATION.--Lat 35'05120", long 81*34,2011, Cherokee County, Hydrologic Unit 03050105, on right bank at downstream side of bridge on U.S. Highway 29, 0.3 mi upstream from Cherokee Creek, .4.4 mi downstream from Gaston Shoals Dam, 4.5 mi east of Gaffney, and at mile 270.3. DRAINAGE AREA.--1,490 m12, approximately. PERIOD OF RECORD.--July 1896 to December 1899 (&age heights and discharge measurements only), October 1938 to September 1971, October 1971 to May 1986 (Crest-Stage partial record), June 1986 to current year. Monthly discharge only for some periods, published in WSP 1303. Discharge for July 12, 1896 to December 31, 1899, published in the 18th, l9th and 21st Annual Reports, Part 4, have been found to be unreliable and should not be used. GAGE.--Water-stage recorder. Datum of gage is 539.10 ft above National Geodetic Vertical Datum of 1929. July 12, 1896 to December 31, 1899, nonrecording gages at sites 1.1 miles upstream at different datum. REMARKS.--Peaks prior to Jan. 1, 1900, are from graphs based on gage readings. Some regulation at medium and low flow by powerplants above station. EXTREMES FOR PERIOD OF RECORD. --Maximum discharge, 119,000 ft3/s, Aug. 14, 1940, gage height, 19.78 ft. STAGE-DISCHARGE RELATION.--Defined by . current-meter measurements below 64,200 fts/s and extended by computation of peak flow over Gaston Shoals Dam. FLOOD-FREQUENCY DATA (ft3 /a) LOG-PEARSON TYPE III STATISTICS (LOG UNITS) 49 YEARS OF RECORD Mean - 4.4979 LOG-PEARSON TYPE III Standard Deviation - 0.2183 31,500 Station Skew = -0.161 Q2 45,800 Q5 Q10 57,700 Q 75 900 Q 25 92:100 50 111,000 Q100 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height year height year height ft) (ft3/s) (ft) (ft3 /a) (ft) (ft3 /a) 1897 Apr. 5 9.25 --- 1956 Apr. 16 10.23 22,400 1976 Oct. 18 11.58 32,100 1898 Sept.23 12.18 --- 1957 Apr. 6 10.40 23,400 1977 Oct. 10 17.24 84,900 1899 Mar. 19 12.70 --- 1958 Apr. 28 12.72 37,900 1978 Nov. 7 12.39 38,100 1939 Aug. 18 10.51 21,000 1959 Sept.30 12.77 38s6OO 1980 July 21 12.33 37,600 1940 Aug. 14 19.78 119,000 1960 Feb. 6 12.63 37,200 1981 Oct. 1 7.56 10,500 1941 July 17 11.43 26,000 1961 June 22 11.00 26,600 1982 Jan. 4 11.84 33,900 1942 Feb. 17 10.70 21,800 1962 Dec. 13 11.31 28,400 1983 Feb. 3 9.98 21,900 1943 Jan. 28 12.39 38,400 1963 Mar. 13 13.03 41,800 1984 Feb. 14 12.67 39,900 1944 Mar. 20 9.82 21,700 1964 Apr. 8 11.44 31,100 1985 Aug. 18 10.78 26,600 1945 Sept.18 15.35 61,600 1965 Oct. 6 15.61 67,100 1986 Aug. 18 7.67 10,900 1946 Jan. 7 13.38 43,400 1966 Mar. 4 11.65 32,600 1987 Mar. 1 15.49 65,800 1947 June 15 11.09 27,800 1967 Aug. 24 11.83 33,800 1988 Jan. 20 7.04 8,770 1948 Aug. 4, 10.80 25,600 1968 Mar. 13 10.65 25,900 1949 Nov. 29 12.47 35,700 1969 Apr. 19 10.57 25,400 1950 Oct. 7 11.70 31,000 1970 Aug. 10 13.50 47,500 1951 Dec. 8 10.47 23,900 1971 Oct. 31 8.55 14,300 1952 Mar. 4 13.52 44,200 1972 Oct. 16 13.43 46,900 1953 Feb. 21 10.13 21,900 1973 Mar. 17 12.99 42,900 1954 Jan. 23 13.24 41,000 1974 Apr. 5 11.91 34,400 1955 Feb. 7 8.55 14,700 1975 Mar. 15 14.37 55,300 69 -- ---- ---- ---- --- SANTEE RIVER BASIN 02154500 NORTH PACOLET RIVER AT FINGERVILLE, SC LOCATION.--Lat 35*0711511, long 81*5911011, S@artanburg County, Hydrologic Unit 03050105, on right bank at McMillin Mill, about 400 ft downstream from Obed Creek, 1.4 mi south of Fingerville, and at mile 48.5. DRAINAGE AREA.--116 m12. PERIOD OF RECORD.--October 1929 to current year. Monthly discharge only for some periods, published in WSP 1303. GAGE.--Water-stage recorder. Datum of gage is 715.56 ft above National Geodetic Vertical Datum of 1929. From November 26, 1929 to November 24, 1933, recording gage at site about 400 ft downstream at datum 5.60 ft higher. REMARKS.--Records good. Some diurnal fluctuation at low and medium flow caused by mill above station. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 12,500 fts/s, August 14, 1940, gage height, 27.13 ft. STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 4,300 fts/s and extended on basis of peak flow over dam 2.0 mi above station. FLOOD-FREQUENCY DATA (fts /a) LOG-PEARSON TYPE III STATISTICS (LOG UNITS) 58 YEARS OF RECORD Mean - .3.474 LOG-PEARSON TYPE III Standard Deviation = 0.264 Q = 3,010 Weighted Skew - -0.119 2 = 4 980 Q5 I Q10 = 61430 Q25 - 81400 Q50 = 9 960 Q100 = 11:600 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height year height year height (ft) (ft3 /s) (ft) (ft3 /a) ft) (ft3 /a) 1931 Dec. 7 872 1951 Dec. 8 9.91 2,320 1971 Oct. 31 8.92 2,020 1932 Dec. 15 2,120 1952 Mar. 4 12.69 3,880 1972 June 21 14.85 4,350 1933 Oct. 17 6,820 1953 Feb. 21 10.01 2,360 1973 May 24 14.77 4,320 1934 Mar. 4 12.00 2,100 1954 Jan. 23 15.96 5,040 1974 Apr. 5 9.71 2,330 1935 July 19 1,760 1955 Feb. 7 8.28 1,840 1975 Mar. 14 14.77 4,320 1936 Apr. 7 19.77 6,120 1956 Apr. 16 7.88 1,690 1976 Oct. 17 10.45 2,630 1937 Oct. 17 21.23 7,290 1957 Apr. 6 10.28 2,620 1977 Oct. 9 18.79 6,370 1938 Oct. 19 17.48 5,400 1958 Apr. 29 12.25 3,480 1978 Jan. 26 9.32 2,180 1939 Aug. 19 10.65 2,480 1959 May 26 18.64 6,680 1979 Sept.30 12.73 3,540 1940 Aug. 14 27.13 12,500 1960 Mar. 31 12.54 3,200 1980 Nov. 3 8.14 1,700 1941 July 17 8.51 1,540 1961 June 22 14.80 4,330 1981 Oct. 1 5.27 608 1942 Feb. 17 11.35 2,700 1962 Dec. 13 13.08 3,480 1982 June 18 11.44 3,030 1943 Jan. 28 10.16 2,200 1963 Mar. 13 14.45 4,010 1983 Apr. 10 7.67 1,540 1944 Mar. 29 9.70 1,620 1964 Aug. 10 9.41 2,440 1984 Feb. 14 13.12 3,700 1945 Sept.17 13.90 3,780 1965 Oct. 5 25.60 11,200 1985 Aug. 18 10.46 2,640 1946 Jan. 7 17.12 5,040 1966 Feb. 14 12.75 3,550 1986 Aug. 18 11.33 2,980 1947 June 15 12.30 3,110 1967 Aug. 24 15.19 4,480 1987 Mar. 1 18.76 6,350 1948 Feb. 13 7.30 1,370 1968 Feb. 13 9.79 2,370 1988 Jan. 20 5.65 731 1949 Nov. 29 13.74 3,780 1969 Sept. 4 10.60 2,690 1950 Oct. 7 16.70 5,150 1970 Nov. 2 6.56 1,070 70 SANTEE RIVER BASIN 02155500 PACOLET RIVER NEAR FINGERVILLE, SC LOCATION.--Lat 35*06135". long 81*57'35", Spartanburg County, Hydrologic Unit 03050105, on right bank, 100 ft upstream from bridge on State Road 55, 0.2 mi downstream from confluence of North Pacolet and South Pacolet Rivers, 2.8 mi southeast of Fingerville. and at mile 46.5. DRAINAGE AREA.--212 m12. PERIOD OF RECCRD.--October 1929 to current year. Monthly discharge only for some periods, published in WSP 1303. REVISED RECORDS.--WSP 1303: 1930-39 (monthly and yearly runoff). GAGE.--Water-stage recorder. Datum of gage is 706.33 ft above National Geodetic Vertical Datum of 1929. REMARKS.--Records good. Some regulation by South Pacolet River Reservoir and Lake William C. Bowen (02154950). Some diurnal fluctuation caused by mill on North Pacolet River. Some water diverted from South Pacolet River above station for City of Spartanburg water supply. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 22,800 ft3/s August 14, 1940, gage height, 22.43 ft. EXTREMES OUTSIDE PERIOD OF RECORD.--Flood of June 1903 reached a stage of 46 ft, from floodmark (discharge not determined). STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 9,600 fts/s and extended by velocity-area studies. Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year h7'ght (ft3/5) year height 3 year height 3 ft) (ft) (ft /a) (ft) (ft /a) 1903 June 0 46.00 1950 Oct. 7 9.05 6,250 1970 Nov. 2 3.50 1,640 1931 Dec. 6 2.68 1.020 1951 Dec. 8 6.85 4,120 1971 Feb. 22 6.23 3,820 1932 Dec. 15 6.45 3,810 1952 Mar. 24 9.46 6,760 1972 June 21 10.15 7,650 1933 Oct. 17 13.31 11,000 1953 Feb. 21 6.27 3,710 1973 Feb. 3 8.58 6,080 1934 Mar. 4 6.39 3,810 1954 Jan. 23 10.38 7,750 1974 Apr. 5 7.16 4,660 1935 Oct. 11 4.76 2,510 1955 Feb. 7 5.10 2,810 1975 Mar. 14 9.88 7,380 1936 Apr. 7 12.53 10,100 1956 Apr. 17 5.55 3,160 1976 Oct. 17 9.69 7,190 1937 Oct. 17 13.63 11,300 1957 Apr. 6 7.33 4,570 1977 Oct. 9 14.89 12,900 1938 Oct. 19 12.73 10,300 1958 Apr. 29 8.20 5.450 1978 Jan. 26 7.58 5,080 1939 Aug. 19 7.09 4,390 1959 May 26 13.82 11,500 1979 Feb. 26 7.81 5,260 1940 Aug. 14 22.43 22,800 1960 Mar. 30 8.78 5,050 1980 May 24 6,500 1941 July 17 3.63 1,760 1961 June 22 8.65 5,850 1981 Oct. 1 3.43 1,580 1942 Feb. 17 9.54 6,760 1962 Apr. 11 6.31 3,710 1982 Feb. 4 7.45 4,920 1943 Jan. 28 6.84 4,120 1963 Mar. 13 10.46 7,860 1983 Apr. 10 5.44 3,140 1944 Mar. 20 6.50 3,870 1964 Aug. 10 7.05 4,560 1984 Feb. 14 6.51 4.060 1945 Sept.17 8.56 5,850 1965 Oct. 5 17.65 16,300 1985 Aug. 18 7.31 4,790 1945 Jan. 7 11.90 9,400 1956 Mar. 4 7.21 4,610 1986 Aug. 18 5.43 3,130 1947 June 15 7.99 5,250 1967 Aug. 24 6,500 1987 Mar. 1 11.71 9,250 1948 Aug. 5 5.62 3,160 1968 Mar. 13 5.83 3,470 1988 Feb. 9 3.94 1,960 1949 Nov. 29 9.66 6,980 1969 Apr. 19 7.71 5,210 71 SANTEE RIVER BASIN 02156000 PACOLET RIVER NEAR CLIFTON, SC LOCATION.--Lat 34*5811011, long 81*48105", Spartanburg County, Hydrologic Unit 03050105, on left bank, 1.0 mi (revised) downstream from dam at Clifton Mill, 1.3 miles southeast of Clifton, 2.7 miles upstream from Lawsons Fork Creek, 2.7 miles northeast of Glendale, and at mile 28.2. DRAINAGE AREA.--320 m12. PERIOD OF RECORD.--October 1939 to September 1978, GAGE.--Water-stage recorder October 1939 to September 1971. Partial record crest gage, October 1971 to September 1978. REKARKS.--Records good. EXTREMES FOR PERIOD OF RECORD. --Maxitm,m discharge, 27,700 fts/s, October 9, 1977, gage height, 21.70 ft. STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 12,100 fts/s and extended on the basis of peak flow over dam computations. Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height year height year height (ft) (ft3 /a) (ft) (ft 3 /a) (ft) (ft3 /a) 1940 Aug. 14 21.19 26,800 1955 Feb. 6 5.35 4,020 1970 July 27 6.16 4,560 1941 July 11 7.74 5,620 1956 Apr. 16 9.63 9,170 1971 Feb. 22 7.17 5,590 1942 Aug. 18 9.76 8,640 1957 Aug. 14 7.51 6,480 1972 June 21 13.39 14tOOO 1943 Jan. 28 11.10 9,300 1958 Nov. 19 12.06 12,600 1973 Feb. 3 11.24 10,800 1944 Mar. 20 8.08 7,220 1959 May 26 12.11 12,600 1974 Apr. 5 8.75 7,400 1945 Aug. 17 14.16 12,000 1960 Feb. 5 10.16 9,840 1975 Mar. 15 12.39 12,500 1946 Jan. 7 12.69 12,900 1961 Feb. 21 9.98 9,050 1976 Oct. 18 11.79 11,600 1947 Jan. 20 6.95 5,860 1962 Apr. 11 9.82 8,770 1977 Oct. 9 21.70 27,700 1948 Aug. 4 6.05 4,690 1963 Mar. 6 14.80 16,100 1978 Jan. 26 11.27 10,800 1949 Nov. 28 9.62 9,170 1964 Aug. 10 14.97 16,400 1950 Oct. 7 14.64 16,300 1965 Oct. 5 17.31 20,100 1951 Dec. 7 7.11 6,100 1966 Mar. 4 10.85 10,200 1952 Mar. 24 11.16 11,400 1967 July 7 9.95 8,940 1953 Feb. 21 6.12 4,800 1968 July 12 9.24 8,010 1954 Jan. 22 9.14 8,520 1969 Apr. 18 9.43 8,260 72 SANTEE RIVER BASIN 02156500 BROAD RIVER NEAR CARLISLE, SC LOCATION.--Lat 34*35'46", long 81*25120", Union County, Hydrologic Unit 03050106, on right bank at downstream side of bridge on State Highway 72, 1.3 mi upstream from Sandy River, 2.0 mi downstream from Seaboard Coast Line Railroad bridge, 2.5 mi east of Carlisle, 5.0 mi downstream from Neals Shoals Damp and at mile 226.0. DRAINAGE AREA.--2,790 m12' approximately. PERIOD OF RECORD.--October 1938 to current year. Monthly discharge only for some periods, published in WSP 1303. REVISED RECORDS.--WSP 892: 1939(M), drainage area. GAGE.--Water-stage recorder. Datum of gage is 290.79 ft above National Geodetic Vertical Datum of 1929. REMARKS.--Records good. Some regulation at low and medium flow by powerplants above station. Capacity of reservoirs insufficient to affect monthly figures of runoff. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 123,000 fts/s, Oct. 10, 1976, gage height, 31.51 ft. STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 65,800 fts/s and extended on basis of computation of peak flow over Neal Shoals Dam. FLOOD-FREQUENCY DATA (ft3/s) LOG-PEARSON TYPE III STATISTICS (LOG UNITS) 50 YEARS OF RECORD Mean . 4.632 LOG-PEARSON TYPE III 15tandard Deviation - 0.184 Q = 41,200 Weighted Skew - 0.050 Q = 64,000 = 84,000 Q 10 = 115 000 Q 25 = 144:000 50 100= 178,000 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height 3 year height year height (ft) (ft Is) (ft) (ft3 /s) (ft) (ft3 /s) 1939 Mar. 1 16.27 34,900 1959 Dec. 30 14.21 28,700 1979 Feb. 26 20.00 47,800 1940 Aug. 15 29.41 103,000 1960 Feb. 7 18.71 42,100 1980 Mar. 29 17.28 37,600 1941 July 18 17.06 37,600 1961 Feb. 22 15.82 33,200 1981 Oct. 2 10.09 15,600 1942 Feb. 18 18.42 42,200 1962 Apr. 12 17.25 37,400 1982 Jan. 5 17.89 39,700 1943 Jan. 29 18.96 44,500 1963 Mar. 14 21.78 57,200 1983 Mar. 18 14.21 27,600 1944 Mar. 20 19.58 46,900 1964 Apr. 8 23.90 69,500 1984 Feb. 15 18.40 41,500 1945 Sept.19 25.72 78,500 1965 Oct. 18 25.82 79,900 1985 Aug. 19 16.72 35,100 1946 Jan. 8 20.11 49,200 1966 Mar. 5 18.89 45,600 1986 Aug. 20 17.33 37,300 1947 Jan. 21 17.21 37,900 1967 Aug. 24 20.23 51,200 1987 Mar. 2 25.77 72,100 1948 Feb. 14 16.20 34,600 1968 Mar. 14 14.57 29,700 1988 Jan. 21 9.15 13,400 1949 Nov. 29 22.81 62,200 1969 Aug. 15 29.41 103,000 1950 Oct. 8 19.32 44,200 1970 Aug. 12 17.48 39,900 1951 Dec. 9 13.65 27,000 1971 Mar. 3 15.05 31,200 1952 Mar. 5 22.43 57,700 1972 Oct. 17 19.31 47,200 1953 Feb. 22 15.77 33,200 1973 Feb. 3 21.54 57,700 1954 Jan. 24 20.63 49,200 1974 Apr. 6 17.61 40,400 1955 Apr. 15 13.79 27,500 1975 Mar. 15 23.75 63,100 1956 Apr. 17 14.99 30,900 1976 Oct. 19 14.95 31,000 1957 Apr. 7 13.24 25,900 1977 Oct. 10 31.51 123,000 1958 Apr. 29 20.12 48,000 1978 Jan. 27 19.72 46,900 iStandard deviation was adjusted according to Appendix 7 of Water Resources Council Bulletin 17-B to adjust the record at Broad River near Carlisle, S.C. (station no. 02156500) to the longer period of record at Broad River at Richtex, S.C. (station no. 02161500). 73 SANTEE RIVER BASIN 02157000 NORTH TYGER RIVER NEAR FAIRMONT, SC LOCATION.--Lat 34*55'45'', long 82*02'40", Spartanburg County, Hydrologic Unit 03050107, on left bank 80 ft downstream from Frey Creek, 2.2 mi north of Fairmont, and at mile 57.9. DRAINAGE AREA.--44.4 mi2. PERIOD OF RECORD.--October 1950 to September 1988. GAGE.--Water-stage recorders and concrete control. Datum of &age is 680 ft above National Geodetic Vertical Datum of 1929. REMARKS.--Records good. EXTREMES FOR PERIOD OF RECORD. --Maximum discharge, 3,610 ft3/s, May 26, 1959, gage height, 13.58 ft. STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 2,100 ft3/s and graphically extended on logarithmic plotting paper. FLOOD-FREQUENCY DATA (ft3 ts) LOG-PEARSON TYPE III STATISTICS (LOG UNITS) 38 YEARS OF RECORD Mean . 3.118 LOG-PEARSON TYPE III Standard Deviation - 0.254 Q2 = 1,350 Weighted Skew - -0.274 Q - 21160 Q5 = 2 720 10 = 31450 Q25 = 3:990 Q50 Q100 = 4,540 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height year height 3 year height 3 (ft) (ft3/s) (ft) (ft /a) (ft) (ft /6) 1951 Dec. 7 8.38 1,510 1966 Mar. 4 9.72 1,930 1981 June 3 3.17 493 1952 Dec. 21 10.55 2,280 1967 Aug. 24 4.44 746 1982 Jan. 4 8.30 1,580 1953 Feb. 21 4.91 722 1968 June 10 6.92 1,240 1983 Mar. 27 3.51 562 1954 Jan. 22 7.15 1,170 1969 Apr. 19 9.99 2,000 1984 Feb. 14 6.80 1,220 1955 May 22 8.68 1,650 1970 Feb. 16 3.05 470 1985 Aug. 17 3.57 574 1956 Apr. 15 9.10 1,790 1971 Feb. 23 4.86 832 1986 Nov. 1 4.43 746 1957 Apr. 5 3.06 466 1972 June 21 9.89 1,970 1987 Mar. 1 9.09 1,770 1958 Nov. 19 8.18 1,480 1973 Sept.14 10.35 2,100 1988 Jan. 20 2.69 397 1959 May 26 13.58 3,610 1974 Jan. 1 4.51 762 1960 Sept. 7 9.13 1,790 1975 Mar. 13 10.10 2,030 1961 Feb. 21 9.26 1,820 1976 Oct. 18 9.13 1,780 1962 Dec. 12 8.08 1,410 1977 Oct. 9 11.30 2,420 1963 Mar. 6 12.48 3,090 1978 Nov. 6 12.70 3,050 1964 Apr. 8 8.57 1,640 1979 Feb. 26 6.21 1,100 1965 Oct. 5 11.64 2,560 1980 May 24 6.53 1,170 74 SANTEE RIVER BASIN 02157500 MIDDLE TYGER RIVER AT LYMAN, SC LOCATION.--Lat 34*5613511, long 82*08'00", Spartanburg County, Hydrologic Unit 03050107, on left bank 200 ft upstream from bridge on State Highway 292 at Lyman, 600 ft downstream from Southern Railway bridge, and 0.8 mi northeast of Duncan. DRAINAGE AREA.--68.3 m12, approximately. PERIOD OF RECORD.--October 1937 to December 1967 and October 1970 to current year. GAGE.--Digital water-stage recorder prior to December 1967, crest-stage gage thereafter. Datum of gage is 776.05 above National Geodetic Vertical Datum of 1929. Prior to February 16, 1965, graphic water-stage recorder at same site and datum. REMARKS.--Records good. Flow regulated by reservoir 5.7 mi above station. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 4,800 ft3/s, August 14, 1940, gage height, 16.16 ft. STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 2,850 fts/9 and extended on basis of computation of peak flow over dam. FLOOD-FREQUENCY DATA (ft3 /a) LOG-PEARSON TYPE III STATISTICS (LOG UNITS) 42 YEARS OF RECORD Mean - 3.398 LOG-PEARSON TYPE III Standard Deviation - 0.129 Q2 - 2,520 Weighted Skew - -0.158 Q 5 = 31220 Q 3,640 Q" 4 140 25 Q 4,490 50 4,830 Q100 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height 3 year height 3 year height 3 (ft) (ft /a) (ft) (ft /a) (ft) (ft /a) 1939 Aug. 18 9.28 2,730 1954 Jan. 23 8.74 2,520 1972 June 21 10.64 3,140 1940 Aug. 14 16.16 4,800 1955 Feb. 7 5.96 1,440 1973 May 28 11.21 3,310 1941 July 18 4.89 945 1956 Apr. 16 7.67 2,160 1974 Jan. 1 7.56 1,970 1942 Feb. 17 9.71 2,860 1957 Apr. 6 6.58 1,710 1975 Mar. 15 10.15 3,000 1943 Jan. 28 8.34 2,380 1958 Apr. 29 7.20 1,960 1976 Oct. 18 7.30 1,870 1944 Mar. 20 7.64 2,120 1959 May 26 10.36 3,070 1977 Oct. 9 11.80 3,490 1945 July 16 8.08 2,310 1960 Mar. 31 7.89 2,240 1978 Nov. 6 13.48 3,990 1946 Jan. 7 12.39 3,670 1961 Aug. 25 7.82 2,240 1979 1947 Jan. 21 6.91 1,840 1962 Dec. 12 11.21 3,310 1980 May 20 8.27 2,260 1948 Aug. 5 11.16 3,310 1963 Mar. 6 12.56 3,730 1981 1949 Nov. 29 10.76 3,190 1964 Apr. 8 8.37 2,300 1982 Feb. 3 9.54 2,770 1950 Oct. 7 6.29 1,580 1965 Oct. 5 12.12 3,590 1983 1951 Dec. 8 6.53 1.660 1966 Mar. 5 9.53 2,760 1984 Feb. 14 9.36 2,690 1952 Mar. 23 10.42 3,070 1967 Aug. 24 7.88 2,110 1985 Aug. 17 10.54 3,110 1953 Feb. 21 6.92 1,840 1971 May 13 5.51 1,150 1986 1987 Mar. 1 11.45 3,380 1988 75 SANTEE RIVER BASIN 02158000 NORTH TYGERRIVER NEAR MOORE, SC LOCATION.--Lat 34*48'10", long 61*57'57", Spartanburg County, Hydrologic Unit 03050107, on right bank at Ott Shoals, 2.0 upstream from Wards Creek, 2.6 mi southeast of Moore, and 5.3 mi upstream from confluence with South Tyger River. DRAINAGE AREA.--162 mi2. PERIOD OF RECORD.--October 1933 to September 1978. Monthly discharge only for some periods, published in WSP 1303. GAGE.--Digital water-stage recorder prior to January 4, 1968, creat-stage gage October 1970 to September 1978. Datum of gage is 564.79 ft above National Geodetic Vertical Datum of 1929. Prior to February 17, 1965, graphic water-stage recorder at same site and datum. REMARKS.--Records good. Some regulation at low flow by powerplants above station. EXTREMES FOR PERIOD OF RECORD. --Maximum discharge, 12,300 ft3/s, August 14, 1940, gage height, 7.15 ft. STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 7,740 ft3/s and extended by velocity-area studies. FLOOD-FREQUENCY DATA (ft3/s) 41 YEARS OF RECORD Mean - 3.571 LOG-PEARSOK TYPE III Standard Deviation - 0.243 Q2 = 3,740 Weighted Skew = -0.042 Q5 = 51960 Q10 = 71600 Q25 = 91830 Q = 11 600 50 = 13:400 Q100 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height year height year height (ft) (ft3 /s) (ft) (ft3 /s) (ft) (ft3 /a) 1935 Aug. 25 3.43 2,010 1950 Oct. 7 6.01 8,120 1965 Oct. 5 5.31 5,930 1936 Apr. 7 6.15 8,640 1951 Dec. 8 3.28 1,950 1966 Mar. 5 4.17 3,450 1937 Oct. 16 5.68 7,160 1952 Mar. 24 4.89 5,030 1967 Aug. 25 3.47 1,880 1938 Oct. 20 5.54 6,680 1953 Feb. 22 3.43 2,160 1971 Oct. 30 3.23 1,580 1939 Aug. 19 3.52 2,240 1954 Jan. 23 4.19 3,510 1972 June 21 4.96 4,900 1940 Aug. 14 7.15 12,300 1955 May 23 3.34 2,020 1973 Sept.15 4.94 4,850 1941 July 17 2.53 1,080 1956 Apr. 16 3.81 2,750 1974 Jan. 1 3.50 1,950 1942 Feb. 18 4.23 3,610 1957 Apr. 7 2.92 1,460 1975 Mar. 15 5.08 5,240 1943 Jan. 29 4.48 4,130 1958 Nov. 19 3.80 2,750 1976 Oct. 18 3.95 2,700 1944 Mar. 21 3.89 2,930 1959 May 26 5.30 6,020 1977 Oct. 9 6.14 8,600 1945 Sept 18 4.00 3,120 1960 Feb. 6 3.93 3,020 1978 Nov. 6 5.34 6,020 1946 Jan. 8 5.21 5,760 1961 Feb. 21 4.78 4,800 1947 Jan. 21 3.46 2,160 1962 Dec. 13 4.47 4,020 1948 Aug. 6 4.27 3,610 1963 Mar. 6 5.54 6,720 1949 Nov. 29 4.78 4,800 1964 Apr. 8 4.98 5,220 76 SANTEE RIVER BASIN 02158500 SOUTH TYGER RIVER NEAR REIDVILLE, SC LOCATION.--Lat 34*52'35", long 82*05'10", Spartanburg County, Hydrologic unit 03050107, on left bank 0.4 mi upstream from bridge on State Highway 296, 1.2 mi downstream from Berry Shoals, 1.8 mi northeast of Reidville, and 4 mi upstream from Bens Creek. DRAINAGE AREA.--106 mi2. PERIOD OF RECORD.--April 1934 to September 1978. GAGE.--Digital water-stage recorder prior to December 5, 1968, crest-stage gage October 1970 to September 1978. Datum of gage is 626.28 ft above National Geodetic Vertical Datum of 1929. Prior to August 4, 1964, graphic water-stage recorder at same site and datum. REMARKS.--Records good. Some regulation at low and medium flow by powerplants above station. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 6,420 ft3/s, October 7, 1949, gage height, 14.23 ft. STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 5,430 ft3/s and graphically extended on logarthmic plotting paper. FLOOD-FREQUENCY DATA (ft3 /s) LOG-PEARSON TYPE III STATISTICS (LOG UNITS) 41 YEARS OF RECORD Mean . 3.390 LOG-PEARSON TYPE III Standard Deviation - 0.218 Q2 = 2,450 Weighted Skew - 0.050 Q 5 = 31750 Q10 4,690 Q25 5,980 Q50 6,990 Q100 8,060 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height year height year height ft) (ft3/s) (ft) (ft 3/a) (ft) (ft 3/a) 1935 Aug. 24 11.05 4,150 1950 Oct. 7 14.23 6,420 1965 Oct. 5 9.29 3,520 1936 Apr. 6 13.66 6,080 1951 Dec. 7 4.88 1,320 1966 Sept.14 7.42 2,510 1937 Oct. 16 9.68 3,880 1952 Mar. 24 9.76 3,930 1967 Aug. 25 5.70 1,650 1938 Oct. 19 10.77 4,330 1953 Feb. 22 5.44 1,570 1971 Oct. 30 4.72 1,200 1939 Aug. 19 5.90 1,820 1954 Jan. 22 7.73 2,780 1972 Oct. 16 5.13 1,390 1940 Aug. 13 12.68 5,510 1955 May 23 6.59 2,190 1973 Sept.14 5.80 1,700 1941 July 19 4.17 982 1956 Apr. 16 6.82 zono 1974 Jan. 1 5.55 1,580 1942 Feb. 18 7.41 2,610 1957 Apr. 6 4.28 1,020 1975 Mar. 15 9.48 3,640 1943 Jan. 28 7.86 2,880 1958 Nov. 19 6.35 2,080 1976 Oct. 18 8.62 3,140 1944 Mar. 20 5.82 1,770 1959 May 26 4.94 1,320 1977 Oct. 9 11.32 4,740 1945 Sept.18 5.19 1,450 1960 Mar. 31 6.08 1,870 1978 Nov. 6 7.88 2,740 1946 Jan. 7 9.52 3,760 1961 Feb. 21 7.97 2,840 1947 Jan. 21 5.29 1,520 1962 Dec. 13 8.16 2,950 1948 Aug. 5 5.06 1,420 1963 Mar. 6 11.00 4,490 1949 Nov. 28 9.51 3,760 1964 Apr. 7 8.33 2,980 77 SANTEE RIVER BASIN 02159000 SOUTH TYGER RIVER NEAR WOODRUFF, SC LOCATION.--Lat 34*45'21", long 81*56'19", Spartanburg County, Hydrologic unit 03050107, on left bank at Chesnee Shoals, 0.5 mi upstream from confluence with North Tyger River and 5.8 mi east of Woodruff. DRAINAGE AREA.--174 mi2. PERIOD OF RECORD.--October 1933 to September 1978. Monthly discharge only for som periods, published in WSP 1303. GAGE.--Water-stage recorder prior to September 1971, crest-stage gage thereafter. Datum of gage is 508.35 ft above National Geodetic Vertical Datum of 1929. REMARKS.--Records good. Some regulation at low and medium flow by powerplants above station. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 9,510 ft 3/s, April 6, 1936, gage height, 9.78 ft. STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 7,670 ft3/s and extended by velocity-area studies. FLOOD-FREQUENCY DATA (ft3 /s) LOG-PEARSON TYPE III STATISTICS (LOG UNITS1 44 YEARS OF RECORD Mean - 3.463 LOG-PEARSON TYPE III Standard Deviation - 0.254 Q2 = 2,880 Weighted Skew - 0.072 Q = 41740 Q5 = 6 180 10 1 Q25 = 8,210 Q50 = 91890 Q100= 11,700 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height year height 3 year height 3 (ft) (ft3 /s) (ft) (ft /a) (ft) (ft /s) 1935 Aug. 25 4.89 2,260 1950 Oct. 7 9.25 8,490 1965 Oct. 16 6.32 4,280 1936 Apr. 6 9.78 9,510 1951 Dec. 8 3.91 1,040 1966 Mar. 5 5.61 3,220 1937 Oct. 16 8.83 8,080 1952 Mar. 24 6.72 4,740 1967 Aug. 25 1,800 1938 Oct. 20 5.85 3,660 1953 Feb. 23 4.62 1,800 1968 June 9 4.98 2,310 1939 Feb. 28 4.82 1,960 1954 Jan. 23 5.40 2,930 1969 Apr. 16 5.13 2,520 1940 Aug. 14 8.18 6,960 1955 May 24 4.52 1,670 1970 Apr. 1 3.72 906 1941 Nov. 13 3.92 1,050 1956 Mar. 16 4.97 2,280 1971 Mar. 3 4.98 2,310 1942 June 10 5.33 2,910 1957 Apr. 7 3.80 950 1972 Oct. 17 5.12 2,510 1943 Jan. 28 5.90 3,540 1958 Nov. 19 5.20 2,640 1973 Sept.15 4.62 1,850 1944 Mar. 20 5.30 2,640 1959 May 25 5.10 2,500 1974 Jan. 1 4.52 1,720 1945 Sept.18 5.61 3,020 1960 Feb. 6 5.19 2,640 1975 Mar. 15 6.86 5,090 1946 Jan. 8 6.31 4,140 1961 Feb. 21 6.31 4,250 1976 Mar. 17 5.70 3,350 1947 Jan. 20 4.79 2,220 1962 Dec. 13 5.70 3,360 1977 Oct. 9 8.62 7,730 1948 Mar. 7 4.27- 1,360 1963 Mar. 6 7.92 6,650 1978 Nov. 6 5.90 3.650 1949 Nov. 29 5.45 2,860 1964 Apr. 8 7.37 5,860 78 SANTEE RIVER BASIN 02159500 TYGER RIVER NEAR WOODRUFF, SC LOCATION.--Lat 34*45115", long 81*55'30", Spartanburg County, Hydrologic Unit 03050107, on left bank at upstream side of Nesbitts bridge on State Highway 49, 0.5 mi downstream from confluence of North Tyger and South Tyger Rivers and 6.5 mi east of Woodruff. DRAINAGE AREA.--351 mi2. PERIOD OF RECORD.--October 1929 to September 1956. GAGE.--Water-stage recorder. Datum of gage is 489.44 ft above National Geodetic Vertical Datum of 1929. REMARKS.--Records good. Some regulation at low and medium flow by powerplants above station. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 28,000 ft3/s,'(estimated) October 2, 1929, gage height, 19.1 ft. EXTREMES OUTSIDE PERIOD OF RECORD.7-Flood on June 6, 1903, reached a stage of 20.4 ft, from floodmark set by local resident, at site 0.3 mi below gage; that in AuSust 1928, 20.0 ft (present site); that in September 1929, 14.65 ft, from floodmarks (discharge, 19,600 ft Is). STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 14,000 fts/s and graphically extended on logarithmic plotting paper. FLOOD-FREQUENCY DATA (ft3 Is) LOG-PEARSON TYPE III STATISTICS (LOG UNITS) 28 YEARS OF RECORD Mean = 3.826 LOG-PEARSON TYPE III Standard Deviation - 0.298 Q = 6 500 Weighted Skew = 0.267 Q 2 = 11:800 5 = 16,400 Q10 Q25 = 23,700 Q50 = 30,200 Q100 w 37,800 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height 3 year height 3 year height 3 (ft) (ft Is) (ft) (ft Is) (ft) (ft /a) 1903 June 6 20.40 1937 Oct. 16 11.48 14,700 1947 Jan. 21 5.49 4,290 1928 Aug. -- 20.00 1938 Oct. 20 9.30 10,600 1948 Aug. 6 5.98 4,800 1929 Sept.-- 14.65 19,600 1939 Aug. 18 5.46 3,830 1949 Nov. 29 8.88 8,740 1930 Oct. 2 19.10 28,000 1940 Aug. 14 13.27 19,200 1950 Oct. 7 12.72 17,200 1931 May 22 5.05 2t430 1941 Nov. 13 4.50 2,220 1951 Dec. 8 5.17 3,000 1932 Jan. 8 6.01 4,350 1942 Feb. 18 6.11 5,450 1952 Mar. 24 8.97 10,000 1933 Oct. 17 7.60 7,840 1943 Jan. 26 7.59 7,780 1953 Feb. 22 5.40 3,710 1934 Mar. 5 5.57 3,540 1944 Mar. 20 6.40 5,270 1954 Jan. 23 6.56 5,990 1935 Aug. 25 5.99 4,350 1945 Sept.18 7.39 6,580 1955 May 23 5.16 3,230 1936 Apr. 5 13.16 17,100 1946 Jan. 8 8.48 9,680 1956 Apr. 17 5.99 4,800 79 BROAD RIVER BASIN 02159600 DUTCHMAN CREEK NEAR PAULINE, S.C. LOCATION.--Lat 34*47'55", long 81'52'46", Spartanburg County, Hydrologic unit 03050107, on downstream side of bridge on county road 90, 75 feet downstream of Smith Creekand 2.2 mi southwest of Pauline. DRAINAGE AREA.--8.97 mi 2 PERIOD OF RECORD.--1967 to 1969; 1974 to current year GAGE.--Water-stage recorder from 1967 to 1969. Crest-stage gage from 1974 to current year. REMARKS.--Records good. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 4,000 ft 3/a, Oct. 9, 1977, gage height 13.61 feet. STAGE DISCHARGE RELATION.--Defined by current-meter measurements below 162 ft 3/a and graphically extended on logarithmic plotting paper. FLOOD-FREQUENCY DATA (ft/s) LOG-PEARSON TYPE III STATISTICS (LOG UNITS1 18 YEARS OF RECORD Mean - 2.932 LOG-PEARSON TYPE III Standard Deviation - 0.359 Q = 882 Station Skew - -0.221 Q 2 = 1730 5 = 2410 Q10 3460 Q25 = = 4220 Q50 5100 Q100 = Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height year height year he (ft) (ft 3 3 (ight 3 /a) (ft) (ft /a) ft) (ft /a) 1967 July 7 6.91 983 1977 Oct. 9 13.61 4,000 1983 Feb. 15 7.80 1t240 1968 Jan. 10 5.69 642 1978 Jan. 26 5.61 622 1984@ Aug. 17 7.60 1,180 1969 Apr. 16 8.73 1,590 1979 Apr. 13 7.78 1,230 1985 Nov. 30 7.75 1,225 1974 Jan. 1 6.15 762 1980 May 20 5.67 637 1986 Jan. 24 3.41 201 1975 Mar. 15 8.41 1,500 1981 Feb. 10 1.10 21 1987 Dec. 28 4.78 430 1976 Oct. 18 10.46 2,310 1982 Dec. 31 8.25 1,420 1988 Mar. 23 3.41 201 80 SANTEE RIVER BASIN 02160000 FAIRFOREST CREEK NEAR UNION, S.C. LOCATION.--Lat 34*4014511, long 81*41'25", Union County, Hydrologic Unit 03050107, on right bank at downstream side of bridge on State Highway 49, 0.3 mi downstream from Buffalo Creek, 4.3 mi southwest of Union, and at mile 7.5. DRAINAGE AREA.--183 m12. PERIOD OF RECORD.--June 1940 to current year. GAGE.--Water-stage recorder prior to September 1971. Crest-stage gage thereafter. Datum of gage is 393.91 ft National Geodetic Vertical Datum of 1929. REMARKS.--Records good. Discharge includes some water diverted from South Pacolet River Reservoir which is discharged into this stream after use. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 11,700 ft3/s, Oct. 9, 1976, gage height 9.43 ft. STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 5,800 ft3/s and graphically extended on logarithmic plotting paper. FLOOD-FREQUENCY DATA (ft3 Is) LOG-PEARSON TYPE III STATISTICS (LOG UNITS) 49 YEARS OF RECORD Mean - 3.585 LOG-PEARSON TYPE III Standard Deviation - 0.216 Q2 = 3,990 Weighted Skew - -0.446 Q5 = 5,880 Q = 71070 10 8,470 Q25 = Q50 = 9,440 Q100 10,400 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height 3 year height year height (ft) (ft /s) (ft) (ft 3/d) (ft) (ft3 /5) 1940 Aug. 14 7.15 6,200 1960 Feb. 7 5.40 2,950 1980 Mar. 29 6.07 4,040 1941 July 17 6.80 5,500 1961 Feb. 22 6.53 4,960 1981 Oct. 1 4.90 2o050 1942 Feb. 17 5.91 3,720 1962 Apr. 12 5.78 3,520 1982 Jan. 4 5.57 3,050 1943 July 9 6.08 4,060 1963 Mar. 7 7.37 6,640 1983 Mar. 18 5.36 2,700 1944 Mar. 20 6.69 5,280 1964 Apr. 8 7.83 7,720 1984 Dec. 7 5.81 3,500 1945 Sept.18 6.94 5,780 1965 Oct. 16 7.53 6,980 1985 Aug. 17 6.50 4,900 1946 Jan. 8 5.25 2,720 1966 Mar. 4 5.69 3,380 1986 Nov. 1 6.81 5,520 1947 Jan. 20 5.75 3,480 1967 Aug. 24 6.42 4,740 1987 Mar. 1 7.22 6,340 1948 Mar. 7 5.07 2,460 1968 Jan. 11 5.60 3,250 1988 Jan. 22 4.05 1,135 1949 Nov. 29 7.61 7,180 1969 Sept. 4 6.85 5,600 1950 Oct. 8 6.42 4,740 1970 Mar. 22 4.43 1,640 1951 Oct. 20 3.90 1,200 1971 Mar. 3 6.33 4,560 1952 Mar. 4 6.56 5,020 1972 June 22 6.04 3,980 1953 May 2 5.52 3,130 1973 Apr. 1 7.46 6,820 1954 Jan. 17 5.77 3,500 1974 Jan. 1 5.75 3,400 1955 Feb. 6 5.13 2,540 1975 Mar. 15 6.94 5,780 1956 Mar. 17 5.55 3,180 1976 Oct. 18 4.98 2,150 1957 Apr. 9 3.77 1,010 1977 Oct. 9 9.43 11,700 1958 Nov. 19 5.91 3,720 1978 Jan. 27 5.86 3,620 1959 Sept.30 5.98 3,860 1979 Apr. 14 6.71 5,320 81 SANTEE RIVER BASIN 02160105 TYGER RIVER NEAR DELTA, SC LOCATION.--Lat 34'32107", long 81*3215411, Union County, Hydrologic Unit 03050107, on right bank at downstream side of bridge on State Highway 72 and 121, 0.9 mi downstream from Seaboard Coast Line Railroad, 0.8 mi southeast of Delta, and at mile 9.0. DRAINAGE AREA.--759 m12. PERIOD OF RECORD.--October 1973 to current year. GAGE.--Water-stage recorder. Elevation of gage is 300 ft above National Geodetic Vertical Datum of 1929 (from topographic map). REMARKS.--Records fair. EXTREMES FOR PERIOD OF RECORD. --Maximum discharge, 30,300 fts/s, Oct. 11, 1976, gage height, 26.31 ft (from floodmarks). STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 16,500 ft3/s and graphically extended on logarithmic plotting paper. FLOOD-FREQUENCY DATA (ft3/s) LOG-PEARSON TYPE III STATISTICS CLOG UNITS) 15 YEARS OF RECORD Mean - 4.015 LOG-PEARSON TYPE III Standard Deviation - 0.214 Q2 = 10,300 Weighted Skew - 0.058 Q5 = 15,600 Q10 = 19,500 Q25 = 24,700 Q = 28 900 50 = 33:200 Q100 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height 3 year height 3 year height (ft) (ft Is) (ft) (ft /5-) ft) (ft 3 /5) 1974 Jan. 2 14.88 7,700 1979 Apr. 14 18.55 13,300 1984 May 8 16.24 9,630 1975 Mar. 15 20.36 16.700 1980 Mar. 29 18.39 13,000 1985 Aug. 19 16.35 9,790 1976 Mar. 17 15.69 8,900 1981 Oct. 1 13.55 6,190 1986 Nov. 22 17.62 11,700 1977 Oct. 11 26.31 30,300 1982 Feb. 5 14.71 7,520 1987 Mar. 2 20.25 16,300 1978 Jan. 27 17.74 11.900 1983 Mar. 18 14.69 7,540 1988 Jan. 21 11.00 3,680 82 SANTEE RIVER BASIN 02160500 ENOREE RIVER AT ENOREE, SC LOCATION.--Lat 34-36'38". long 81*54'35", Spartanburg Courty, Hydrologic Unit 03050108, on left bank 60 ft upstream from bridge on State Highway 49, 0.6 mi upstream from Warrior Creek, 4.0 mi southeast of Enoree, and at mile 47.7. DRAINAGE AREA.--307 m12. PERIOD OF RECORD.--August 1929 to current year. GAGE.--Water-stage prior to September 1976. Crest-stage gage thereafter. Datum of gage is 448.13 ft above National Geodetic Vertical Datum of 1929. Prior to November 20, 1929, nonrecording gage at same site and datum. REM ARKS.--Records good. Some regulation at low and medium flow by power plants above station. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 30,000 ft3/s, Oct. 2, 1929, gage height 10.5 ft (from floodmark). STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 20,200 ftsts and graphically extended on logarithmic plotting paper. FLOOD-FREQUENCY DATA (ft3 /a) LOG-PEARSON TYPE III STATISTICS (LOG UNITS)- 59 YEARS OF RECORD Mean = 3.800 LOG-PEARSON TYPE III Standard Deviation - 0.249 Q2 = 6,230 Weighted Skew - 0.040 Q 5 = 10,100 Q 13,100 Q10 17,200 Q 25 20,500 50 24,100 Q100 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height 3 year height year height ft) (ft /a) (ft) (ft3 /a) (ft) .(ft 3 /a) 1930 Oct. 2 10.50 30,000 1950 Oct. 8 6.93 13,000 1970 Mar. 22 3.61 2,080 1931 May 22 3.76 3,100 1951 Dec. 8 3.44 1,960 1971 Mar. 3 5.05 5,530 1932 Dec. 4 5.29 7,100 1952 Mar. 29 5.82 8,960 1972 June 21 5.91 8,740 1933 Oct. 17 6.04 9,500 1953 Feb. 22 4.29 4,110 1973 Sept.14 6.49 11,100 1934 June 5 4.58 5,400 1954 Jan. 17 5.00 6,120 1974 Jan. 2 4.48 4,060 1935 Aug. 25 5.70 8,430 1955 Feb. 7 4.23 4,010 1975 Mar. 14 6.40 10,700 1936 Apr. 7 7.86 17,200 1956 Mar. 17 4.86 5,670 1976 Oct. 19 4.69 4,540 1937 Oct. 16 7.14 13,800 1957 Mar. 1 3.53 2,350 1977 Oct. 9 7.09 13,700 1938 Oct. 20 5.86 8,960 1958 Nov. 19 5.12 6,430 1978 Jan. 27 5.22 6,130 1939 Aug. 18 4.35 4,270 1959 May 25 4.19 3,810 1979 Apr. 26 5.50 7,140 1940 Aug. 14 6.86 12,800 1960 Feb. 6 4.91 5,970 1980 Mar. 29 4.92 5,160 1941 July 10 3.68 2,690 1961 Feb. 22 5.70 8,600 1981 Oct. 1 3.80 2,780 1942 Feb. 17 4.82 5,520 1962 Dec. 13 5.52 7,740 1982 Jan. 5 5.62 7,600 1943 Jan. 29 5.52 7,740 1963 Mar. 7 6.76 12,600 1983 Mar. 18 4.19 3,420 1944 Mar. 20 5.43 7,570 1964 Apr. 8 6.95 13,200 1984 May 7 5.23 6,170 1945 Sept.18 5.11 6,430 1965 Oct. 16 5.57 7,980 1985 Feb. 4 4.09 3,210 1946 Jan. 7 5.85 8,960 1966 Mar. 5 5.30 7,070 1986 Nov. 22 4.06 3,150 1947 Jan. 20 4.96 5,970 1967 Feb. 18 3.99 3,250 1987 Mar. 1 7.04 13,500 1948 May 28 4.30 4,140 1968 June 8 4.50 4,650 1988 Jan. 22 3.58 2,170 1949 Nov. 29 6.18 10,200 1969 Jan. 21 5.17 5,940 83 SANTEE RIVER BASIN 02160700 ENOREE RIVER AT WHITMIRE, SC LOCATION '--Lat 34*30'33", Ions 81*35'54", Union County, Hydrologic Unit 03050108, on left bank, at upstream side of bridge on U.S. Highway 176, 0.4 mi downstream from Seaboard Coast Line Railroad, 0.5 mi northeast of Whitmire, and at mile 19.2. DRAINAGE AREA.--444 m12. PERIOD OF RECORD.--October 1973 to current year. GAGE.--Water-stage recorder. Datum of gage is 300.00 ft above National Geodetic Vertical Datum of 1929. REMARKS.--Records fair. EXTREMES FOR PERIOD OF RECORD. --Maximum discharge, 19,700 ft3/s, Oct. 10, 1976. STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 11,000 ft3/s and graphically extended on logarithmic plotting paper. FLOOD-FREQUENCY DATA (ft3/s) LOG-PEARSON TYPE III STATISTICS (LOG UNITS) 15 YEARS OF RECORD Mean - 3.747 LOG-PEARSON TYPE III Standard Deviation - 0.238 Q2 = 5,450 Weighted Skew - 0.268 Q = 81770 5 = 11,400 Q10 = Q 15,300 25 18,600 Q50 Q100 22,200 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height year height year height (ft) (ft3 /s) (ft) (ft3/s) ft) (ft3/s) 1974 Jan. 3 24.11 3,980 1979 Apr. 15 26.45 6,790 1984 May 8 25.70 5,920 1975 Mar. 15 28.92 10,800 1980 Mar. 29 26.43 6,760 1985 Feb. 4 22.93 3,420 1976 Mar. 18 24.76 4,860 1981 Oct. 2 21.54 2,510 1986 Nov. 22 24.58 4,690 1977 Oct. 10 32.58 19,700 1982 Jan. 5 26.23 6,560 1987 Mar. 2 27.86 8,780 1978 Jan. 27 26.20 6,540 1983 Mar. 28 23.36 3,710 1988 Jan. 22 21.41 2,530 84 SANTEE RIVER BASIN 02161500 BROAD RIVER AT RICHTEX, SC LOCATION.--Lat 34*11'05", long 81*11'48", Richland County, Hydrologic Unit 03050106, on right bank 0.8 mi west of Richtex 1.2 mi upstream from Little River, 10.2 mi downstream from Parr Shoals Dam, and at mile 191.2. DRAINAGE AREA.--4,850 m12, approximately. PERIOD OF RECORD.--October 1925 to September 1983. Monthly discharge only for some periods, published in WSP 1303. REVISED RECORDS.--WSP 757: 1930(M). WSP 972: Drainage area. WSP 1383: 1929(M), 1933. GAGE.--Water-stage recorder. Datum of gage is 184.84 ft above National Geodetic Vertical Datum of 1929. REMARKS.--Records good. Regulation at low and medium flow by powerplant above station. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 228,000 ft3/s, Oct. 3, 1929, gage height, 30.7 ft (from floodmarks). STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 82,800 ft3/s and extended on basis of computation of peak flow over Parr Shoals Dam. FLOOD-FREQUENCY DATA (ft3/s) LOG-PEARSON TYPE III STATISTICS (LOG UNITS) 58 YEARS OF RECORD Mean - 4.642 LOG-PEARSON TYPE III Standard Deviation - 0.210 = 59,000 Station Skew . 0.636 Q2 Q5 = 89,700 Q 10 = 115,000 Q = 153,000 Q 25 = 187 000 50 = 225'000 Q100 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year h7ight (ft3/s) year height (ft3 year height 3 ft) (ft) /a) (ft) (ft /s) 1926 Jan. 20 12.01 40,300 1946 Jan. 9 13.86 59,200 1966 Mar. 6 14.79 65,300 1927 Feb. 25 9.14 28,400 1947 Jan. 21 13.72 57,800 1967 Aug. 25 16.09 74,500 1928 Aug. 17 30.10 222,000 1948 Feb. 14 12.40 49,400 1968 Jan. 12 11.90 46,200 1929 Sept.28 18.32 88,200 1949 Nov. 30 18.59 95,700 1969 Apr. 19 12.91 52,700 1930 Oct. 3 30.70 228,000 1950 Oct. 9 12.75 52tOOO 1970 Aug. 12 10.97 40,600 1931 Dec. 7 7.81 23,000 1951 Dec. 9 9.18 30,600 1971 Mar. 4 13.73 . 58,000 1932 Jan. 9 14.18 51,200 1952 Mar. 6 17.39 84,700 1972 June 23 14.18 61,600 1933 Oct. 18 19.72 101t000 1953 Feb. 23 11.15 42,000 1973 Feb. 4 16.04 74,100 1934 Mar. 29 10.48 34,400 1954 Jan. 24 14.68 64,700 1974 Apr. 6 12.11 47,500 1935 Oct. 12 17.86 84,600 1955 Apr. 15 11.36 43,200 1975 Mar. 16 18.52 94,900 1936 Apr. 8 24.96 157,000 1956 Mar. 16 11.24 42,000 1976 Oct. 20 10.03 35,200 1937 Oct. 18 16.12 72,400 1957 Apr. 7 9.35 31,800 1977 Oct. 11 23.67 146,000 1938 Oct. 21 13.53 55,800 1958 Nov. 21 13.35 55,900 1978 Jan. 27 14.79 64,500 1939 Mar. 2 13.12 53,400 1959 Dec. 30 9.31 31,200 1979 Feb. 26 15.80 72,300 1940 Aug. 16 21.08 120,000 1960 Oct. 1 55t9OO 1980 Mar. 30 14.74 64,200 1941 July 7 12.41 49,400 1961 Feb. 25 13.50 56,600 1981 Oct. 1 12.07 46,700 1942 Feb. 18 12.99 53,300 1962 Jan. 7 13.42 55,900 1982 Jan. 5 14.43 62,100 1943 Jan. 30 13.63 57,200 1963 Mar. 8 16.18 75,300 1983 Mar. 19 12.41 48,400 1944 Mar. 21 17.40 84,700 1964 Apr. 9 19.00 99,500 1945 Sept.19 18.68 96,600 1955 Oct. 18 19.25 102,000 85 SANTEE RIVER BASIN 02162010 CEDAk CREEK NEAR BLYTHEWOOD, SC LOCATION.--Lat 34*11'44", long 81*06'13", Richland County, Hydrologic Unit 03050106, on right bank, at downstream side of bridge on State Road 59, 0.2 mi above Williams Branch, 8.0 mi southwest of Blythewood, and at mile 6.9. DRAINAGE AREA.--48.9 m12. PERIOD OF RECORD.--November 1966 to September 1983; February 1985 to current year. GAGE.--Water-stage recorder. Elevation of gage is 240 ft above National Geodetic Vertical Datum of 1929 (from topographic map). REMARKS.--Records good. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 4,870 ft 3/s, July 4, 1968, gage height, 18.42 ft. STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 3,730 fts/s and graphically extended on logarithmic plotting paper. FLOOD-FREQUENCY DATA (ft3/s) STATISTICS (LOG UNITS) 121 YEARS OF RECORD Mean - 3.430 GRAPHICAL SOLUTION Standard Deviation - 0.063 Q 2 = 2,780 2Station Skew = -1.410 Q = 3,930 Q 5 = 41390 10 4,750 Q25 Q 50 = 4 900 Q100 = 5:150 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height 3 year height 3 year height 3 (ft) (ft /s) (ft) (ft /s) (ft) (ft /a) 1967 Aug. 23 9.34 1,890 1977 Mar, 13 15.97 3,990 1987 Jan. 19 13.53 2,550 1968 July 4 18.42 4,870 1978 May 9 14.01 3,250 1988 Apr. 11 6.23 689 1969 Apr. 16 16.30 4,060 1979 Jan, 23 15.03 3,560 1970 Mar. 22 11.29 2,300 1980 Mar, 29 13.76 3,110 1971 Mar. 3 12.81 2,830 1981 Feb@ 11 12.34 2,630 1972 Jan. 11 8.55 1,460 1982 Jan, 1 14.17 3,260 1973 Feb. 3 16.03 3,960 1983 Mar, 17 16.22 4,000 1974 Apr. 5 9.14 1,640 1984 1975 July 15 13.26 2,990 1985 June 30 5.28 436 1976 Mar. 16 12.24 2,630 1986 Mar, 19 8.86 1,360 1The frequency relation for this stream had a sharp break at about the 5-year recurrence interval because of a change in storage where flow breaks out of a deeply incised main channel. The logarithms of annual peak discharges for this station could not be fitted to a Pearson type III distribution; therefore, the flood frequency was determined graphically. 2Station skew computed using graphical frequency relation. 86 SANTEE RIVER BASIN 02162500 SALUDA RIVER NEAR GREENVILLE, SC LOCATION,--Lat 34*50'32", long 82*28'51", Pickens County, Hydrologic Unit 03050109, on right bank 700 ft upstream from bridge on State Road 124, 1.6 mi donstream from Saluda Lake Dam, 2.4 mi upstream from Georges Creek, 4.6 mi west of City Hall in Greenville, and at mile 132.0. DRAINAGE AREA.--295 m12. PERIOD OF RECORD.--October 1941 to September 1978, October 1980 to current year. Monthly discharge only for some periods, published in WSP 1303. GAGE.--Water-stage recorder until 1978, crest-stage gage thereafter. Elevation of gage is 797.48 ft above National Geodetic Vertical Datum of 1929. REMARKS.--Records good. Some regulation at low and medium flow by powerplant at Saluda Lake. Capacity of reservoirs insufficient to affect monthly figures of runoff. About 41,688,041 gal per day or 64.5 ft3/s diverted above station for City of Greenville water supply during water year. City of Greenville began diverting water from Saluda River (Table Rock Reservoir) in 1930; supplemented by North Saluda Reservoir in 1961. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 11,000 ft3/s, Oct. 7, 1949, gage height, 19.38 ft. STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 7,540 fts/s and extended on basis of computation of peak flow over the dam at Saluda Lake. FLOOD-FREQUENCY DATA (ft3 /s) LOG-PEARSON TYPE III STATISTICS (LOG UNITS) 43 YEARS OF RECORD Mean - 3.658 LOG-PEARSON TYPE III Standard Deviation - 0.184 Q2 4,560 Weighted Skew = -0.035 Q 5 61490 Q 71800 Q 10 25 9,480 Q50 = 10,800 Q100 , 12,000 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height year height year height (ft) (ft3ls) (ft) (ft3/s) (ft) (ft3/a) 1942 Feb. 17 11.63 5,980 1957 Apr. 6 9.62 4,780 1972 June 21 9.86 5,380 1943 Dec. 30 11.01 5,620 1958 Apr. 29 6.65 2,970 1973 May 28 12.36 6,960 1944 Mar. 30 8.37 4,060 1959 June 1 7.65 3,580 1974 Jan. 1 7.56 3,830 1945 Mar. 27 6.26 2,740 1960 Mar. 31 7.56 3,520 1975 Mar. 14 13.78 7,540 1946 Jan. 8 14.48 7,720 1961 June 23 15.43 8,300 1976 May 30 8.01 4,160 1947 Jan. 20 7.42 3,460 1962 Dec. 12 12.04 6,220 1977 Mar. 30 11.38 6,310 1948 Aug. 5 6.87 3,140 1963 Mar. 6 10.43 5,260 1978 Jan. 26 9.15 4,950 1949 July 13 12.12 6,280 1964 Apr. 8 9.57 4,760 1981 Oct. 1 5.11 1,900 1950 Oct. 7 19.38 11,000 1965 Oct. 5 18.14 10,100 1984 Dec. 11 8.43 4,450 1951 Dec. 8 6.76 3,080 1966 Feb. 14 10.62 5,390 1985 Aug. 17 7.38 3,680 1952 Mar. 23 10.94 5,560 1967 Aug. 24 14.19 7,530 1986 Nov. 30 5.23 2,020 1953 Feb. 22 8.87 4,360 1968 Mar. 13 7.46 3,500 1987 Mar. 2 11.60 6,430 1954 Jan. 23 15.05 8,040 1969 Apr. 18 9.23 4,770 1988 Aug. 5 5.47 2,235 1955 Feb. 7 7.85 3,700 1970 Aug. -8 5.95 2,580 1956 Apr. 16 7.38 3,460 1971 Oct. 30 5.54 2,290 87 SANTEE RIVER BASIN 02153000.SALUDA RIVER NEAR PELZER, SC LOCATION.--Lat 34*40'05", long 82*27'55", Anderson County, Hydrologic Unit 03051009, on right bank, 0.4 mi downstream from Hurricane Creek, 1.9 mi north of Pelzer, and at mile 114.2. DRAINAGE AREA.--405 m12. PERIOD OF RECORD.--December 1929 to 1978. GAGE.--Crest-stage gage 1972-88. Elevation of gage is 727.75 ft above National Geodetic Vertical Datum of 1929. REMARKS.--Records good. Some regulation at low and medium flow by powerplant above station. EXTREMES FOR PERIOD OF RECORD. --Maximum discharge, 13,600 ft3/s, Oct. 7, 1949, gage height, 10.53 ft. STAGE-61SCHARGE RELATION. --Defined by current-meter measurements below 11,300 ftS/s and graphically extended on logarithmic plotting paper. FLOOD-FREQUENCY DATA (ft3/s) LOG-PEARSON-TYPE III STATISTICS (LOG UNITS) 57 YEARS OF RECORD Mean = 3.798 LOG-PEARSON TYPE III Standard Deviation = 0.179 Q2 = 6,380 Weighted Skew = -0.238 Q5 = 8,910 Qlo = 10,500 Q25 = 12,500 Q50 = 13,900 Q100 15,200 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Di:ch;rge Water Date Gage Discharge year height 3 year height 3 year h7ight (ft3/s) (ft) (ft /s) (ft) t s) ft) 11929 Sept.27 5.80 6,460 1949 Nov. 29 7.37 8,270 1969 Apr. 18 7.86 8,960 1930 Oct. 2 6.88 9,400 1950 Oct. 7 10.53 13,600 1970 Aug. 9 4.00 2,850 1931 May 22 3.90 2,750 1951 Dec. 8 4.76 41120 1971 Mar. 3 4.52 3,630 1932 Dec. 15 5.08 4,900 1952 Mar. 24 7.40 8,370 1972 June 21 6.24 6,280 1933 Oct. 17 6.39 7,990 1953 Feb. 22 5.82 5,720 1973 May. 29 6.16 6,160 1934 Mar. 5 5.80 6,460 1954 Jan. 24 7.89 9,220 1974 Apr. 5 5.10 4,500 1935 Jan. 10 5.54 5,760 1955 Feb. 7 5.28 4,920 1975 Mar. 15 7.72 8,720 1936 Apr. 7 10.26 13,300 1956 Apr. 16 5.88 5,880 1976 Jan. 28 5.62 5,290 1937 Jan. 3 8.00 9,390 1957 Apr. 6 5.75 5,720 1977 Mar. 30 7.80 8,860 1938 Oct. 19 8.54 10,200 1958 Apr. 29 5.25 4,760 1978 Jan. 26 1939 Aug. 20 6.24 6,360 1959 June 1 4.97 4,440 1979 Apr. 26 6.57 6,810 1940 Aug. 14 8.31 9,920 1960 Mar. 31 5.43 5,080 1980 Jan. 18 5.92 5,770 1941 July 9 3.76 2,540 1961 June 23 7.87 9,220 1981 Oct. 1 6.09 6,040 1942 Feb. 17 6.66 7,180 1962 Dec. 13 8.11 9,560 1982 Feb. 3 6.20 6,220 1943 Jan. 28 6.49 6,840 1963 Mar. 6 8.53 10,200 1983 1944 Mar. 20 5.78 5,720 1964 Apr. 8 8.60 10,200 1984 Dec. 12 5.60 5,260 1945 Mar. 27 4.57 3,720 1965 Oct. 6 9.63 12,000 1985 Aug. 17 5.03 4,400 1946 Jan. 7 8.63 10,400 1966 Mar. 4 6.62 6,890 1986 NOV. 30 3.85 2,640 1947 Jan. 20 5.75 5,720 1967 Aug. 25 7.46 8,280 1987 Mar. 1 7.50 8,350 1948 Aug. 6 4.28 3,340 1968 Dec. 12 5.32 4,830 1988 Jan. 20 4.26 3,240 iNo record Oct 1 to Aug 31. 88 SANTEE RIVER BASIN 02163500 SALUDA RIVER NEAR WARE SHOALS, SC LOCATION.--Lat 34*23'01", long 82*13112", Greenwood County, Hydrologic Unit 03050109, on right bank 2.0 mi southeast of Ware Shoals, 2.5 mi downstream from Ware Shoals Dam, 5.0 mi upstream from Turkey Creek, and at mile 83.7. DRAINAGE AREA.--581 m12. PERIOD OF RECORD.--October 1938 to current year. Monthly discharge only for some periods, published in WSP 1303. GAGE.--Water-stage recorder and data collection platform. Elevation of gage is 438.15 ft above National Geodetic Vertical Datum of 1929. REMARKS.--Records good. Some regulation at low and medium flow by powerplants upstrea m. Capa%ity of reservoirs insufficient to affect monthly figures of runoff. About 41,517,000 gal per day or 64.2 ft /s diverted above station for City of Greenville water supply during water year. City of Greenville began diverting water from Saluda River (Table Rock Reservoir) in 1930; supplemented by North Saluda Reservoir in 1961. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 20,700 ft.3/s, Sept. 14, 1973, gage height, 22.85 ft. STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 13,800 ft3/s and extended by indirect computation of'peak flow over dam. FLOOD-FREQUENCY DATA (ft,3 /s) LOG-PEARSON TYPE III STATISTICS (LOG UNITS) 50 YEARS OF RECORD Mean - 3.947 LOG-PEARSON TYPE III Standard Deviation - 0.218 Q2 = 9,180 Weighted Skew - -0.430 Q5 = 13,600 Q = 16,440 Q 10 . 19 700 25 1 Q50 = 22,000 Q100 = 24,200 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height 3 year height year height (ft) (ft /5) (ft) (ft3 /5) (ft) (ft3 /a) 1939 Aug. 18 14.29 10,500 1959 June 2 9.92 5,070 1979 Feb. 25 15.05 9,150 1940 Aug. 13 20.48 20,600 1960 Oct. 11 11.37 5,970 1980 Mar. 28 14.36 8,460 1941 July 7 9.27 5,010 1961 Feb. 22 17.91 12,600 1981 Oct. 1 6.02 2,660 1942 Mar. 21 13.67 8,300 1962 Dec. 13 18.52 13,600 1982 Jan. 4 15.38 9,510 1943@ Jan. 18 18.18 15,300 1963 Mar. 6 21.12 17,600 1983 Apr. 10 9.24 4,390 1944 Mar. 20 16.45 11,700 1964 Apr. 8 20.63 16,700 1984 Dec. 6 14.81 8,910 1945 Sept.13 10.99 5,970 1965 Oct. 5 18.17 13,000 1985 Aug. 18 9.08 4,290 1946 Jan. 7 17.71 14,300 1966 Mar. 4 16.06 10,300 1986 Nov. 30 7.25 3,270 1947 Jan. 20 13.25 7,880 1967 Aug. 25 12,000 1987 Mar. 2 15.67 9,840 1948 July 16 10.48 5,410 1968 July 10 18.16 12,900 1988 Jan. 21 7.69 3,490 1949 Nov. 29 19.12 16,500 1969 Jan. 20 17.06 11,500 1950 Oct. 8 18.45 14,900 1970 Mar. 22 7.04 2,840 1951 Dec. 8 9.11 4,740 1971 Mar. 3 16.38 10,700 1952 Mar. 24 19.20 14,100 1972 Jan. 10 15.96 10,200 1953 Feb. 21 13.59 8,180 1973 Sept.14 22.85 20,700 1954 Jan. 24 15.34 9,700 1974 Jan. 1 14.36 8,460 1955 Feb. 7 12.38 7,090 1975 Sept.18 17.42 12,000 1956 Sept.26 14.61 9,080 1976 Mar. 16 13.87 7,980 1957 Apr. 7 11.27 5,830 1977 Oct. 9 16.47 10,800 1958 Nov, 19 16.48 10,400 1978 Jan. 26 15.92 10,100 89 SANTEE RIVER BASIN 02165000 REEDY RIVER NEAR WARE SHOALS, SC LOCATION.--Lat 34*25'02'', long 82*09'10", Laurens County, Hydrologic Unit 03050109, on downstream side of State Road S-30-36 bridge, 5.5 mi northeast of Ware Shoals, 6.0 mi downstream from Boyd Mill Dam, and at mile 8.7. DRAINAGE AREA.--236 mi2. PERIOD OF RECORD.--March 1939 to current year. REVISED RECORDS.--WSP 892: 1939. WSP 922; Drainage area. WSP 1723: 1940, 1943, 1948-49, 1952(M). WSP 1904: 1940, 1943, 1946, 1949, 1952. WDR-SC-77-1: Drainage area. WDR-SC-78-1: Drainage area. GAGE.--Water-stage recorder. Datum of &age is 453.86 ft above National Geodetic Vertical.Datum of 1929. Prior to Oct. 1, 1977, at site 4.1 mi upstream at datum 26.76 ft higher. REMARKS.--Records good. Some regulation at low and medium flow by powerplants above station. Capacity of reservoirs insufficient to affect monthly figures of runoff. Diversion into basin by City of Greenville above station 02163500. EXTREMES FOR PERIOD OF RECORD. --Maximum discharge, 11,000 ft3/s, Sept. 14, 1973, gage height, 15.40 ft. STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 7,650 ft3/s and graphically extended on logarithmic plotting paper. FLOOD-FREQUENCY DATA (ft3/s) LOG-PEARSON TYPE III STATISTICS (LOG UNITS) 49 YEARS OF RECORD Mean = 3.624 LOG-PEARSON TYPE III Standard Deviation = 0.237 Q2 = 4,290 Weighted Skew = -0.196 Q = 6 700 Q5 I 10 = 81400 Q2.5 = 10,600 Q50 = 12,200 Q100 13,900 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height 3 year height 3 year height 3 (ft) (ft /5) (ft) (ft /s) (ft) (ft /a) 1940 Aug. 14 13.32 9,410 1960 Oct. 11 5.76 3,620 1980 Mar. 29 12.23 4,210 1941 July 17 4.40 2,380 1961 Feb. 22 11.18 7,940 1981 Feb. 12 7.64 1,390 1942 Feb. 18 6.50 4,270 1962 Dec. 13 10.97 7,800 1982 Jan. 5 13.86 5,120 1943 Jan. 19 9.69 6,960 1963 Mar. 7 14.92 10,600 1983 Mar. 28 8.60 2,100 1944 Mar. :91 7.41 4,840 1964 Apr. 9 11.84 8,390 1984 Dec. 7 12.55 4,370 1945 Sept.17 4.64 2,580 1965 Oct. 6 7.54 5,320 1985 Feb. 2 8.84 2,280 1946 Jan. 8 10.44 7,380 1966 Mar. 5 6.94 4,830 1986 Nov. 30 7.56 1,560 1947 Jan. 21 5.48 3,470 1967 Jan. 9 4.45 2,370 1987 Mar. 2 13.96 5,080 1948 Mar. 8 4.74 2,680 1968 July 10 8.31 5,920 1988 Jan. 21 8.06 1,740 1949 Nov. 29 10.54 7,520 1969 Apr. 20 7.22 5,150 1950 Oct. 8 7.56 5,370 1970 Mar. 23 3.58 1,600 1951 Sept. 8 4.28 2,220 1971 Mar. 3 5.66 3,820 1952 Mar. 5 8.60 6,120 1972 June 22 11.20 7,940 1953 Feb. 22 5.31 3,200 1973 Sept.14 15.40 11,000 1954 Jan. 17 7.12 4,960 1974 Jan. 2 5.63 3,790 1955 Feb. 8 5.02 2,960 1975 Feb. 22 11.38 8,070 1956 Sept.27 6.29 3,970 1976 Oct. 19 5.58 3,740 1957 Apr. 6 3.87 1,830 1977 Dec. 9 9.67 6,870 1958 Nov. 20 7.88 5,600 1978 Oct. 27 12.90 4,020 1959 Sept. 9 4.15 2,130 1979 Apr. 14 13.71 4,950 90 SANTEE RIVER BASIN 02165200 SOUTH RABON CREEK NEAR GRAY COURT, SC LOCATION.--Lat 34*31'12", long 82*09'26", Laurens County, Hydrologic Unit 03050109, on left bank, 125 ft upstream from U.S. Highway 76, 2.5 mi upstream from North Rabon Creek and 7.0 mi southwest of Gray Court. DRAINAGE AREA.--29.5 mi2. PERIOD OF RECORD.--January 1967 to September 1981. GAGE.--Water-stage recorder. Datum of gage is 548.37 ft National Geodetic Vertical Datum of 1929. REMARKS.--Records good. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 4,100 ft3/s Sept. 14, 1973; gage height, 9.86 ft. STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 1,170 ft3/s and graphically extended on logarithmic plotting paper. FLOOD-FREQUENCY DATA (ft3 /s) LOG-PEARSON TYPE III STATI TICS (LOG UNITS) 15 YEARS OF RECORD Mean 2.912 LOG-PEARSON TYPE III Standard Deviation . 0.330 Q2 = 812 Weighted Skew = 0.038 Q 5 = 11540 Q 2,160 Ql' 3 110 25 1 Q 3,940 50 4,870 Q100 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height year height 3 year height ft) (ft3 13) (ft) (ft /a) (ft) (ft 3/5) 1967 July 8 1.91 353 1972 Jan. 11 4.31 1,240 1977 Oct. 9 4.60 1,490 1968 Jan. 10 3.41 803 1973 Sept.14 9.86 4,100 1978 Jan. 26 3.77 1,020 1969 Jan. 20 4.06 998 1974 Jan. 1 2.91 684 1979 Sept.30 1.93 282 1970 Mar. 22 2.04 379 1975 Mar. 14 5.17 1,660 1980 Apr. 15 3.49 874 1971 Mar. 3 4.19 1,190 1976 Mar. 16 3.30 780 1981 Oct. 1 1.70 219 91 SANTEE RIVER BASIN 02167000 SALUDA RIVER AT CHAPPELLS, SC LOCATION.--Lat 34*10'4011, long 81*51'40", Newberry County, Hydrologic Unit 03050109, an left bank on downstream side of bridge on State Highway 39 at Chappells, 6.7 mi downstream from dam at Lake Greenwood, 9.8 mi upstream from Little River, and at mile 52.3. DRAINAGE AREA.--1,360 m12. PERIOD OF RECORD.--October 1926 to current year. Monthly discharge only for some periods, published in WSP 1303. Gage-height records collected since 1905 are contained in reports of National Weather Service. GAGE.--Water-stage recorder and data collection platform. Datum of &age is 362.89 ft above National Geodetic Vertical Datum of 1929. Oct. 1, 1926 to Sept. 30, 1939, nonrecording or recording gage at site 300 ft downstream at datum 363.79 ft above mean sea level. Oct. 1, 1939 to Oct. 7, 1964, recording gage at present site and at datum 363.89 ft above mean sea level. REMARKS.--Peaks are from graphs based on gage readings by the U.S. Weather Bureau prior to June 27, 1927. Peak discharges since May 1940 affected by storage in Lake Greenwood. EXTREMES FOR PERIOD OF RECORD.--Maxirm discharge, 63,700 ft3/s, Oct. 2, 1929, gage height 32.5 ft, present datum. EXTREMES OUTSIDE PERIOD OF RECORD.--The flood of Aug. 26, 1908 reached a stage of 36.7 ft (present site and datum), from reports of National Weather Service. STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 27,000 fts/a and extended on basis of velocity-area studies. Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height year height year height (ft) (ft3 /a) (ft) (ft3 /a) (ft) (ft3/.) 1888 Sept.-- 30.60 1933 Oct. 19 21.28 19,200 1961 Feb. 26 20.71 17,400 1906 Dec. 22 18.60 1934 June 7 20.94 18,000 1962 Jan. 7 17.64 10,200 1907 Oct. 5 13.30 1935 Oct. 12 17.22 9,700 1963 Mar. 13 22.78 24,300 1908 Aug. 26 34.70 1936 Apr. 8 28.60 49,400 1964 Apr. 8 24.98 33,200 1909 June 5 20.50 1937 Jan. 5 22.03 21,400 1965 June 16 21.35 16,400 1910 Mar. 3 17.60 1938 Oct. 22 20.91 18,000 1966 Mar. 5 21.41 16,600 1911 Oct. 9 12.20 1939 Mar. 1 19.07 13,200 1967 Aug. 26 19.01 10,800 1912 Mar. 16 25.00 1940 Aug. 14 28.66 49,700 1968 Jan. 11 16.90 8,300 1913 Mar. 16 22.00 1941 July 17 14.96 7,400 1969 Apr. 19 24.32 26,200 1914 Dec. 31 16.70 1942 Mar. 22 22.82 24,300 1970 Mar. 22 13.02 5,510 1915 Jan. 8 16.50 1943 Jan. 29 22.21 22,100 1971 Mar. 4 22.51 19,800 1916 Feb. 4 20.30 1944 Mar. 21 24.84 32,300 1972 June 22 21.69 17,400 1917 Mar. 6 19.00 1945 Sept.18 13.52 6,080 1973 Apr. 2 22.75 20,600 1918 Aug. 4 17.00 1946 Jan. 8 22.30 22,500 1974 Apr. 5 14.74 6,800 1919 Oct. 28 22.60 1947 Jan. 21 15.68 8,100 1975 Mar. 15 24.84 28,300 1920 Dec. 12 19.50 1948 Apr. 1 19.52 14,200 1976 Mar. 17 19.03 10.800 1921 Feb. 11 22.50 1949 Nov. 29 24.59 31t400 1977 Oct. 9 26.47 35,200 1922 Feb. 17 20.00 1950 Mar. 7 12.46 5,310 1978 Jan. 27 15.48 7,740 1923 Mar. 18 18.80 1951 Apr. 3 12.39 5,430 1979 Feb. 26 21.74 17,500 1924 July 10 16.80 1952 Mar. 25 24.68 31,900 1980 Mar. 29 24.24 25,800 1925 Jan. 20 20.50 1953 Feb. 25 13.70 6,380 1981 Oct. 1 18.06 9,870 1926 Jan. 20 15.50 1954 Jan. 24 13.57 6,320 1982 Jan. 4 23.05 21,600 1927 Dec. 30 15.30 7,700 1955 Apr. 15 13.78 6,460 1983 Apr. 9 15.72 7,900 1928 Aug. 17 29.97 56,200 1956 Apr. 18 18.79 12,400 1984 Dec. 7 22.60 20,200 1929 Sept.28 30.90 60,700 1957 Apr. 5 12.48 5,590 1985 Feb. 7 6,000 1930 Oct. 2 31.50 63,700 1958 Nov. 20 19.14 13,200 1986 Dec. 1 14.66 7,140 1931 Apr. 1 12.49 5,310 1959 June 3 .12.28 5,390 1987 Mar. 3 20.11 13,300 1932 Jan. 9 20.51 16,800 1960 Feb. 14 21.00 18,300 1988 Feb. 4 10.31 4,380 92 SANTEE RIVER BASIN 02167500 SALUDA RIVER NEAR SILVERSTREET LOCATION.--Lat 34*11', long 81*441, Newberry County, Hydrologic Unit 03050109, on left bank 200 ft upstream from Higgins Perry Bridge on State Highway 19, 1 mi downstream from Little River, and 2.5 mi south of Silverstreet. DRAINAGE AREA.--1,620 m12, approximately. PERIOD OF RECORD.--October 1926 to June 1966 (discontinued). Monthly discharge only for some periods, published in WSP 1303. GAGE.--Water-stage recorder. Datum of gage is 345.13 ft above mean sea level, unadjusted. Prior to Oct 15, 1929, staff gage at same site and datum. Since Mar 8, 1939, water-stage recorder for station on Lake Murray near Columbia has been used as an auxiliary gage for this station. REMARKS.--Records fair. Flow regulated by Lake Greenwood. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 83,800 fts/s Oct. 3, 1929, gage height, 33.97 ft. STAGE-DISCHARGE RELATION.--Defined by current-meter measurements below 28,000 fts/s and extended on basis of discharge measurements made at Chappells near Chapin. Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height 3 year height 3 year height (ft) (ft /a) (ft) (ft /a) (ft) (ft3 /8) 1928 Aug. 18 30.60 60,400 1943 Jan. 30 21.66 20,100 1958 Nov. 21 15,400 1929 Sept.28 32.05 69,800 1944 Mar. 21 26.93 39,100 1959 Sept.30 6,860 1930 Oct. 3 33.97 83,800 1945 Apr. 27 15.46 9,130 1960 Feb. 14 22.54 21,100 1931 Apr. 2 12.87 6,180 1946 Jan. 9 22,800 1961 Feb. 26 22.30 20,600 1932 Jan. 10 21.12 18,600 1947 Jan. 21 18.12 13,000 1962 Jan. 7 20.39 15,800 1933 Sept. 8 21.52 19,600 1948 Apr. 2 20.40 14,600 1963 Mar. 14 24.12 26,300 1934 June 7 20.84 18,000 1949 Nov. 30 25.80 32,200 1964 Apr. 9 27.10 39,500 1935 Oct. 11 17.22 11,500 1950 Mar. 8 14.43 6,860 1965 June 17 22.15 20,200 1936 Apr. 8 31.89 63,000 1951 Apr. 4 14.07 6,970 1937 Jan. 6 21.98 20,900 1952 Mar. 25 25.34 28,400 1938 Oct. 23 19.73 15,800 1953 Feb. 25 14.20 6,860 1939 Mar. 2 20.00 16,300 1954 Apr. 2 14.96 7,760 1940 Aug. 15 30.29 58,300 1955 Apr. 15 16.88 10,400 1941 July 18 15.08 8,610 1956 Apr. 18 18,62 13,200 1942 Mar. 23, 22.96 23,700 1957 Apr. 6 14.21 6,620 93 SANTEE RIVER BASIN 02169000 SALUDA RIVER NEAR COLUMBIA, SC LOCATION.--Lat 34*00'50", long 81*05'17", Richland County, Hydrologic Unit 03050109, on left bank 0.4 mi upstream from site of Old Saluda Mill, 1.6 mi upstream from confluence with Broad River and 3.3 mi west of State Capital in Columbia, and at mile 1.67. DRAINAGE AREA.--2,520 m12. PERIOD OF RECORD.--August 1925 to current year. GAGE.--Water-stage recorder and data collection platform. Datum of gage is 149.46 ft above National Geodetic Vertical Datum of 1929. Prior to Sept. 1, 1929, at same site at datum 150.46 ft above mean sea level. REMARKS.--Records good. Flow regulated by Lake Murray and Lake Greenwood. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 67,000 ft3/s, Oct. 2, 1929, gage height, 15.22 ft. STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 36,000 fts/s and extended on basis of discharge measurements made at Wise Ferry Bridge near Chapin. Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height year height year height (ft) (ft3 /a) (ft) (ft3/s) ft) (ft3/s) 1926 Mar. 31 7.75 23,300 1951 Aug. 10 6.29 10,300 1976 July 7 7.99 18,400 1927 July 20 5.62 12,300 1952 June 12 6.39 10,700 1977 Mar. 22 7.95 18,200 1928 Aug. 18 13.04 58,200 1953 Sept. 3 6.13 9,600 1978 Jan. 26 7.80 17,400 1929 Mar. 6 12.43 53,600 1954 Nov. 9 6.10 9,600 1979 Feb. 26 9.53 27,200 1930 Oct. 2 15.22 67,000 1955 Aug. 19 6.03 9,250 1980 Mar. 30 31,000 1931 Sept.11 5.86 9,590 1956 Aug. 15 5.65 8,080 1981 July 11 7.68 16,300 1932 Sept.13 6.12 10,300 1957 Sept. 3 6.07 10,300 1982 Jan. 4 8.30 19,600 1933 Feb. 20 9.04 24,500 1958 Jan. 24 6.77 13,100 1983 Apr. 8 8.54 21,000 1934 Nov. 2 6.44 11,500 1959 Sept.30 6.26 10,300 1984 Aug. 9 8.03 18,100 1935 Sept. 5 7.17 14,800 1960 Feb. 13 7.02 13,200 1985 Feb. 5 7.99 18,400 1936 Apr. 7 14.53 61,600 1961 Apr. 12 7.33 15,200 1986 Sept.26 7.75 17,100 1937 Apr. 9 8.74 23,000 1962 Mar. 13 6.83 13,100 1987 Aug. 26 7.69 16,700 1938 Nov. 15 6.28 11,600 1963 Mar. 13 6.83 13,100 1988 Oct. 29 7.21 14,200 1939 Sept. 8 6.04 9,950 1964 Apr. 10 11.25 38,800 1940 Aug. 28 5.95 9,950 1965 June 16 13.32 53,200 1941 Dec. 13 6.15 10,700 1966 Mar. 4 7.16 14,300 1942 June 10 6.92 13,500 1967 Aug. 24 12,000 1943 July 22 6.09 10,300 1968 Jan. 10 7.44 15,700 1944 Mar. 24 9.15 25,700 1969 Apr. 19 10.82 35,700 1945 Sept.17 6.13 10,300 1970 Aug. 31 6.48 11,400 1946 Apr. 26 9.71 28,700 1971 Aug. 17 8.31 20,400 1947 Dec. 7 6.13 10,300 1972 Jan. 11 7.93 18,200 1948 Apr. 8 8.31 20,400 1973 Apr. 7 8.63 22,300 1949 May 1 9.16 25,700 1974 Feb. 25 8.48 21,400 1950 Nov. 22 6.38 10,700 1975 Feb. 19 8.22 19,800 94 SANTEE RIVER BASIN 02169500 CONGAREE RIVER AT COLUMBIA, SC LOCATION.--Lat 33*59'35", long 81*03'00", Lexington County, Hydrologic Unit 03050110, on right bank at Columbia, 1,000 ft downstream from Gekvais Street Bridge, 1.4 mi downstream from confluence of Broad and Saluda Rivers, and at mile 174.8. DRAINAGE AREA.--7,850 m12, approximately. PERIOD OF RECORD.--October 1939 to current year. Gage-height records collected at site 1,000 ft upstream October 1891 to December 1933 and at present site since January 1934 are contained in reports of National Weather Service. GAGE.--Water-stage recorder. Datum of gage is 113.02 ft above National Geodetic Vertical Datum of 1929. REMARKS.--Records good. Flow regulated by Lake Murray and Lake Greenwood on the Saluda River and to some extent, at low and medium flow, by powerplants on the Broad River. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 155,000 ft3/s, Oct. 11, 1976, gage height, 29.74 ft. EXTREMES OUTSIDE PERIOD OF RECORD. --Maximum flood since at least October 1891, discharge 364,000 ft3/s, Aug. 27, 1908, gage height, 39.8 ft, present datum, at site 1,000 ft upstream, from records of National Weather Service. STAGE-DISCHARGE RELATION, --Defined by current-meter measurements below 150,000 ft3/s and extended logarithmically. Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height 3 year height 3 year height ft) (ft /a) (ft) (ft /s) (ft) (ft3 Is) 1852 Sept.-- 34.40 1926 Feb. 26 13.00 51,100 1961 Feb. 25 21.08 74,400 1892 Jan. 20 24.60 154,000 1927 Feb. 25 10.20 39,100 1962 Jan. 8 19.69 65p2OO 1893 Aug. 29 '21.10 110,000 1928 Aug. 18 33.50 311,000 1963 Mar. 15 23.09 91,800 1894 Oct. 24 12.70 49,800 1929 Mar. 1 25.90 173,000 1964 Apr. 10 28.60 142,000 1895 Oct. 10 20.40 103,000 1930 Oct. 3 33.10 303,000 1965 Oct. 18 26.18 120,000 1896 Feb. 7 17.80 79,600 1931 Dec. 8 6.70 26,800 1966 Mar. 6 21.74 60,600 1897 Feb. 7 21.50 115,000 1932 Jan. 10 16.70 71,600 1967 Aug. 25 23.78 97,900 1898 Sept.25 10.20 39,100 1933 Oct. 19 21.50 115,000 1968 Jan. 12 18.81 61,200 1899 Feb. 8 21.70 117,000 1934 Mar. 29 12.70 33,400 1969 Apr. 19 23.37 94,200 1900 Apr. 22 22.00 120,000 1935 Oct. 12 23.30 92,300 1970 Aug. 12 15.44 45,200 1901 Apr. 3 23.00 132,000 1936 Apr. 8 33.34 231,000 1971 Mar. 4 21.55 79,100 1902 Mar. 2 22.00 120,000 1937 Oct. 19 20.56 70,900 1972 Jan. 12 19.26 63,900 1903 June 9 27.20 194,000 1938 Oct. 21 18.42 57,900 1973 Apr. 2 23.%9 99,800 1904 Aug. 10 12.20 47,500 1939 Mar. 2 19.93 66,400 1974 Jan. 2 16.87 51,600 1905 Feb. 22 14.70 59,400 1940 Aug. 16 26.14 121,000 1975 Mar. 16 26.47 122,000 1906 Dec. 22 20.30 102,000 1941 July 18 17.19 52,000 1976 Mar. 17 16.16 48,400 1907 June 3 9.00 34,500 1942 Feb. 19 17.31 52,400 1977 Oct. 11 29.74 155,000 1908 Aug. 27 39.80 364,000 1943 Jan. 20 19.44 63,400 1978 Jan. 28 21.87 81,700 1909 June 5 22.00 120,000 1944 Mar. 21 24.57 105,000 1979 Feb. 26 23.46 94,500 1910 Mar. 3 13.80 54,900 1945 Sept.20 24.30 102,000 1980 Mar. 30 23.29 93,100 1911 Oct. 9 10.90 41,900 1946 Jan. 9 19.21 62,200 1981 Oct. 2 16.81 51,300 1912 Mar. 17 30.70 256,000 1947 Jan. 21 19.42 63,400 1982 Jan. 6 22.20 84,200 1913 Max. 16 23.20 135,000 2948 Feb. 14 17.72 54,400 1983 Mar. 18 19.65 66,000 1914 Dec. 31 14.60 58,900 1949 Nov. 30 25.56 116,000 1984 Feb. 16 20.30 70,300 1915 Jan. 8 17.40 76,500 1950 Oct. 9 16.77 50,200 1985 Aug. 19 17.52 54,700 1916 July 17 31.50 272,000 1951 Dec. 9 12.27 32,000 1986 Nov. 23 18.37 58,900 1917 Mar. 6 17.80 79,600 1952 Mar. 6 23.20 91,400 1987 Mar. 3 26.67 123,000 1918 Jan. 31 12.20 47,500 1953 Feb. 23 15.28 43,500 1988 Jan. 23 9.78 24,700 1919 Oct. 28 20.70 106,000 1954 Jan. 25 19.66 65,200 1920 Aug. 28 19.50 94,100 1955 Apr. 151, 16.06 47,000 1921 Feb. 11 24.30 149,000 1956 Apr. 18 15.22 43,100 1922 Feb. 17 22.20 123,000 1957 Apr. 7 12.00 31,000 1923 Mar. 18 17.70 78,800 1958 May 1 19.46 64,000 1924 Jan. 18 15.60 64,600 1959 Sept.30 17.63 53,900 1925 Jan. 20 23.50 139,000 1960 Oct. 1 19.68 65,200 95 SANTEE RIVER BASIN 02169550 CONGAREE CREEK AT CAYCE, S.C. LOCATION.--Lat 33*5611511, long 81*04140", Lexington County, Hydrologic Unit 03050110, on left bank 20 it downstream from bridge on U.S. Highway 21 at Cayce, 2.1 mi upstream from Sixmile Creek, and at mile 5.4. DRAINAGE AREA.--122 m12. PERIOD OF RECORD.--October 1959 to September 1980 (discontinued). Occasional low-flow measurements, water years 1925, 1944, 1949-59. GAGE.--Water-stage recorder. Datum of &age is 128.98 it National Geodetic Vertical Datum of 1929 (South Carolina Highway Department benchmark). Prior to Jan. 20, 1960, nonrecording gage at same site and datum. REMARKS. --Records good. About 3.3 ft3/s diverted by City of Cayce for municipal supply. EKTREMES FOR PERIOD OF RECORD.--Maxirmim discharge, 1,840 fts/s, Oct. 1, 1959, gage height, 5.92 ft-.f;om floodmarks. STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 1,560 ft3/s and graphically extended on logarithmic plotting paper. FLOOD-FREQUENCY DAT (it 3/a) LOG-PEARSON TYPE III STATISTICS (LOG UNITS) 21 OF RECOU Mean . 2.940 LOG= WN TYPE III Standard Deviation - 0.139 Q2 - 856 Weighted Skew . 0.310 Q5 - 1,130 Q 10 - 11320 Q25 - 1,580 Q 1 770 50 - 1:970 Q100 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height year height 3 year height 3 3 (ft) (it /s) (it) (it /a) it) (it /3) 1960 Oct. 1 5.92 1,840 1970 Aug. 12 4.55 800 1980 Mar. 29 4.29 650 1961 Aug. 5 4.81 1,050 1971 Mar. 4 5.09 1,140 1962 Feb. 23 4.55 912 1972 Jan. 11 4.29 650 1963 Jan. 21 4.14 666 1973 June 23 4.98 1,070 1964 Aug. 30 4.84 1,090 1974 Jan. 2 4.19 565 1965 Oct. 16 5.61 1,630 1975 July is 4.77 932 1966 Mar. 4 4.18 596 1976 July 6 4.58 818 1967 Aug. 25 4.77 932 1977 Dec. 13 4.49 764 1968 Jan. 11 4.18 596 1978 Jan. 26 4.27 640 1969 Apr. 17 4.63 848 1979 Feb. 25 4.99 1,070 96 SANTEE RIVER BASIN 02169630 BIG BEAVER CREEK NEAR ST. MATTHEWS. S.C. LOCATION.--Lat 33-44'12", long 80'57'30", Calhoun County, Hydrologic Unit 03050110, on right downstream wingwall of bridge on U.S. Highway 21, 0.1 mi downstream from Rock Branch, 11.6 mi northwest of St. ,Matthews, and at mile 8.2. DRAINAGE AREA.--10.0 m12. PERIOD OF RECORD.--July 1966 to current year. GAGE.--Water-stage recorder. Datum of gage is 164.21 ft National Geodetic Vertical Datum of 1929. REMARKS.--Records good. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 1,360 ft3/s, July 29, 1971, gage height, 6.66 ft. STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 207 ft3/s and graphically extended on logarithmic plotting paper. FLOOD-FREQUENCY DATA (ft3j.) STATISTICS (LOG UNITS) :MOF RECORD Mean . 1.958 19AYP @OLUTION 2Standard Deviation - 0.350 Q = 86 Station Skew = 0.469 Q 2 = 165 Q 5 = 260 Q 10 = 425 25 = 571 50 = 745 Q100 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height 3 year height 3 year height 3 ft) (ft /s) (ft) (ft /s) (ft) (ft /a) 1967 Aug. 23 3.53 58 1977 June 20 3.33 54 1987 June 19 3.32 87 1968 June 9 240 1978 June 6 4.05 112 1988 June 26 3.15 77 1969 Apr. 16 3.88 97 1979 Sept. 5 4.73 272 1970 Mar. 22 4.02 118 1980 Mar. 13 3.66 68 1971 July 29 6.66 1,360 1981 Aug. 17 3.79 95 1972 Aug. 24 3.97 101 M2 Dec. 31 3.59 63 1973 Feb. 2 4.29 157 1983 Dec. 31 3.66 86 1974 Aug. 6 3.71 73 1984 May 30 4.34 180 1975 July 24 4.10 120 1985 Feb. 6 3.21 74 1976 Jan. 27 3.33 52 1986 Nov. 22 3.57 98 1The logarithms of annual peak discharges could not be fitted to a Pearson type III distribution because of storage in ponds ; therefore, a graphical solution was used that followed the systematic record at the lower end and the WRC weighted estimate at the upper end of the flood frequency curve. 2Station skew computed using graphical frequency relation. 97 SANTEE RIVER BASIN 02170000 SANTEE RIVER AT FERGUSON, SC LOCATION.--Lat 33*2611511, long 80'16120", at Ferguson, Orangeburg County, Hydrologic Unit 03050111, 4 miles downstream from Eutaw Creek, inundated by Lake Marion, since 1942. DRAINAGE AREA.--14,600 m12. PERIOD OF RECORD.--S*pt. 21, 1907 to Nov. 22, 1921 (U.S. Weather Bureau), Nov. 23, 1921 to Sept. 30, 1941. GAGE.--Non recording prior to Nov. 23, 1921, recording thereafter. Datum of gage is 42.30 ft National Geodetic Vertical Datum of 1929, supplementary adjustment of 1936. REMARKS.--Gags heights prior to Nov. 23, 1921, furnished by the U.S. Weather Bureau. Peaks affected since August 1929 by storage in Lake Murray and to a lesser degree since 1904 by storage in reservoirs on Catawba, Wateree, and Broad Rivers. 3 EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 374,000 ft /s, July 21, 1916, gage height 24.74 ft. STAGE-DISCHARGE RELATION--Defined by current-meter measurements below 260,000 ft /a and extended on basis of velocity-area studies. FLOOD FREQUENCY DATA--Flow records at this site were affected by regulation and were not used in the regionalization analyses. Site is currently inundated by Lake Marion; therefore frequency data were not computed. Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height (ft3 year height 3 year h7ight (ft3/5) (ft) /8) (ft) (ft /5) ft) 1908 Aug. 31 23.70 344,000 1923 Mar. 23 15.20 89,000 1938 Oct. 27 13.54 38,000 1909 June 10 15.62 1D1,000 1924 Jan. 23 13.87 50,000 1939 Mar. 7 15.1 86,000 1910 Mar. 7 13.90 50,000 1925 Jan. 23 17.13 146,000 1940 Aug. 21 14 07 56 000 215*98 348:000 1911 Jan. 10 13.47 38,000 1926 Mar. 3 13.43 35,900 1941 July 23 1912 Mar. 20 19.44 215,000 1927 Mar. 2 13.30 32,500 1913 Mar. 21 15.56 101,000 1928 Aug. 22 20.60 251,000 1914 Jan. 6 14.02 53,000 1929 Mar. 10 17.55 160,000 1915 Jan. 24 14.65 71,000 1930 Oct. 7 21.04 263,000 1916 July 21 24.74 374,000 1931 Jan. 19 12.88 26,000 1917 Mar. 10 14.70 74,000 1932 Jan. 15 13.95 53,000 1918 Feb. 6 13.90 50,000 1933 Jan. 3 114.08 56,000 1919 July 27 17.12 146,000 1934 June 11 13.80 47,000 1920 Apr. 3 14.00 53,000 1935 Oct. 17 13.81 47,000 1921 Feb. 15 17.47 158,000 1936 Apr. 11 20.42 245,000 1922 Feb. 21 15.77 106,000 1937 Jan. 11 14.19 59,000 10ccurred on June 12, 1934. 2Affected by backwater; occurred on July 25, 1941. 3Maximum daily discharge. 98 SANTEE RIVER BASIN 02171500 SANTEE RIVER NEAR PINEVILLE, S.C. LOCATION.--Lat 33*27'15", long 80*09'25", Berkeley County, Hydrologic Unit 03050112, on right bank 2.4 mi downstream from Lake Marion Dam, 3.0 mi upstream from Dead River, 6.7 mi west of Pineville, and at mile 85.0. DRAINAGE AREA.--14,700 m12, approximately. PERIOD OF RECORD.--April 1942 to current year. GAGE.--Water-stage recorder. Datum of gage is 23.00 ft National Geodetic Vertical Datum of 1929 (levels by South Carolina Public Service Authority). Prior to Feb. 25, 1943, nonrecording gage at site 2.2 mi upstream of temporary water-stage recorder operated by Corps of Engineers, at site 200 ft upstream, at different datum. REMARKS.--Records good. Flow completely regulated by Lake Marion. Water is diverted above station from Lake Marion through canal into Lake Moultrie for generation of power and for navigation, then discharged into Cooper River basin. EXTREMES FOR PERIOD OF RECORD.-- Maximum discharge, 155,000 ft3/s, Sept. 23, 1945, gage height, 31.1 ft (from floodmarks). STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 9,830 fts/s and extended by computation of peak flow over spillway at Lake Marion. FLOOD-FREQUENCY DATA--Frequency analysis not performed on Santee River near Pineville, SC, because regulation pattern has been altered since rediversion in 1986. Peak Stages and Discharges Water Date Gage Drischarge Water Date Gage Discharge Water Date Gage Discharge year height 3 year height 3 year height 3 (ft) (ft /a) (ft) (ft /s) (ft) (ft /a) 1943 Mar. 27 23.23 32,300 1958 Nov. 30 25.85 59,700 1973 Apr. 7 25.24 50,100 1944 Mar. 24 29.52 122,000 1959 July 27 12.36 6,840 1974 Feb. 16 21,94 21,300 1945 Sept.23 31.10 155,000 1960 Feb. 18 26.57 69,300 1975 Mar. 19 27.91 91,700 1946 Jan. 9 25.50 55,800 1961 Mar. 3 24.68 46,500 1976 May. 8 6.49 2,340 1947 Feb. 8 30.04 132,000 1962 Mar. 17 24.03 36,100 1977 Oct. 14 26.01 60,200 1948 Feb. 17 26.35 73,800 1963 Mar. 18 25.43 52,200 1978 Jan. 31 24.74 43.900 1949 Dec. 4 28.56 114,000 1964 Apr. 13 27.07 77,200 1979 Mar. 2 27.74 85,000 1950 Aug. 29 782 1965 Oct. 22 27.41 88,100 1980 Mar. 30 26.58 67,900 1951 June 24 617 1966 Mar. 9 24.94 51,400 1981 Mar. 16 7.01 2,640 1952 Mar. 11 27.77 89,900 1967 Aug. 26 25.42 52,400 1982 Jan. 10 26.88 72,000 1953 Mar. 25 7.15 2,830 1968 Jan. 17 22.77 23,000 1983 Apr. 16 24.73 32,300 1954 Apr. 17 3.53 1,140 1969 Apr. 20 24.87 45,500 1984 Dec. 13 13.65 25,600 1955 Oct. 15 2.34 653 1970 Mar. 24 24.03 36,400 1985 Feb. 12 9.55 3,900 1956 Apr. 7 2.51 744 1971 Mar. 8 25.51 53,600 1986 Dec. 6 22.24 116,600 1957 Apr. 6 3.12 989 1972 Jan. 21 21.64 19,800 1987 Mar. 6 --- 87,000 1988 Oct. 3 --- 1850 iDaily discharge from one-dimensional model. SANTEE RIVER BASIN 02171560 SANTEE RIVER NEAR RUSSELLVILLE, SC LOCATION.--Lat 33*29138", long 80*57'38", Berkeley County, Hydrologic Unit 03050112, on downstream side of U.S. Highway 52 bridge, 5.2 mi northeast of Russellville, and at mile 63.7. DRAINAGE AREA.--Indeterminate. PERIOD OF RECORD.--October 1978 to current year. GAGE.--Water-stage recorder and data collection platform. Datum of gage is 10.59 ft above National Geodetic Vertical Datum of 1929. REMARKS.--Discharge records for 1986-88 are computed by utilization of the One-Dimensional unsteady flow simulation model. Flow completely regulated by Lake Marion. EXTREMES FOR PERIOD OF RECORD. --Maxitmm daily discharge, 133,000 ft3/s, Mar. 3, 1979; gage height, 26.54 ft. 3 STAGE-DISCHARGE RELATION--Defined by discharge measurements below 105,000 ft /a and extended graphically on logarithmic plotting paper. FLOOD-FREQUENCY DATA--Frequency analysis is not performed for this station because regulation pattern has been altered since rediversion in 1986. Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height 3 year height 3 year height 3 (ft) (ft Is) (ft) (ft /a) ft) (ft /a) 1979 Mar. 3 26.54 133,000 1984 May 14 121.74 36,100 1980 Apr. 1 24.45 70,400 1985 Feb. 13 14 '48 2 2,430 1981 Mar. 17 5.38 1,150 1986 Nov. 29 --- 10,800 1982 Jan. 11 24.37 68,800 1987 Mar. 7 --- 215,800 1983 Apr. 16 23.13 47,000 1988 Feb. 22 --- 1,900 1September 6, backwater from rediversion 2Daily discharge from one-dimensional model 100 SANTEE RIVER BASIN 02171650 SANTEE RIVER BELOW ST. STEPHENS, SC LOCATION.--Lat 33*2410511, long 79*51'20", Berkeley County, Hydrologic Unit 03050112, on right bank, on Tract 13P of Francis Marion National Forest, 3.9 mi east of St. Stephens, 600 ft downstream from Mattassee Lake, and at mile 52.0. DRAINAGE AREA--14,900 mi 2. approximately. - PERIOD OF RECORD--October 1970 to September 1981. GAGE--Water-stage recorder. Datum of gage is 0.23 ft; National Geodetic Vertical Datum of 1929. REMARKS.--Records poor. 3 EXTREMES FOR PERIOD OF RECORD--Maximum discharge, 96,900 ft Mar 21_22, 1975 gage height, 29.67 ft. 3 STAGE-DISCHARGE RELATION--Defined by current meter measurements below 83,700 ft /a and extended graphically on logarithmic plotting paper. FLOOD-FREQUENCY DATA--Frequency analysis not performed for this station because regulation pattern has been altered since rediversion in 1986. . Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year blight (ft3/s) year height 3 year height 3 ft) (ft) (ft /a) (ft) (ft Is) 1971 Mar. 10 25.77 66,200 1976 July 1 9.00 2,150 1981 Mar. 18 --- 1,300 1972 Jan. 23 21.29 22,700 1977 Oct. 17 25.93 58,900 1973 Apr. 9 25.32 61,800 1978 Feb. 3 24.96 50,600 1974 Feb. 21 20.64 19,600 1979 Mar. A 28.98 89,600 1975 Mar. 21 29.67 98,900 1980 Apr. 4 27.52 73,400 101 SANTEE RIVER BASIN 02171680 WEDBOO CREEK NEAR JAMESTOWN, S.C. LOCATION.--Lat 33*19'50", long 79*48'10", Berkeley County, Hydrologic Unit 03050112, on right downstream wingwall of culvert on State Highway 45, 1.4 mi southeast of Alvin, 3.3 mi upstream from mouth, and 7.5 mi northwest of Jamestown. DRAINAGE AREA.--17.4 mi2. PERIOD OF RECORD.--September 1966 to February 1972, February 1973 to current year. GAGE.--Water-stage recorder. Elevation of gage is 20 ft (from topographic map). REMARKS.--Records fair. EXTREMES FOR PERIOD OF RECORD. --Maximum discharge, unknown, probably exceeded 1300 ft3/s (possible backwater from swamp), Sept. 5, 1987, gage height, 7.59 ft; maximum gage-height, 9.49 ft, Mar. 10, 1987 (caused by backwater from Santee River). STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 700 ft3/s and graphically extended on logarithmic plotting paper. FLOOD-FREQUENCY DATA (ft3/s) LOG-PEARSON TYPE III STATISTICS (LOG UNITS) 21 YEARS OF RECORD Mean = 2.399 LOG-PEARSON TYPE III Standard Deviation - 0.386 Q2 260 Weighted Skew - -0.248 Q5 535 Q10 765 Q 1,100 Q 25 1,380 Q 510 11690 100 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height year he year height 3 3 (ight 3 (ft) (ft /s) (ft) (ft /5) ft) (ft /s) 1967 July 31 4.68 80 1977 Dec. 12 4.31 198 1987 Mar. 1 4.68 294 1968 Aug. 11 3.42 47 1978 May 9 4.45 232 1988 Sept.10 3.83 104 1969 Aug. 5 4.98 286 1979 Sept. 5 5.31 546 1970 Mar. 22 4.25 159 1980 Apr. 14 5.19 490 1971 Aug. 26 5.96 928 1981 Apr. 2 1.99 11 1972 Feb. 3 4.97 408 1982 June 19 5.15 473 1973 Apr. 10 5.86 856 1983 Mar. 25 5.84 840 1974 Feb. 8 4.69 297 1984 May 4 4.16 161 1975 Mar. 22 8.82 348 1985 Aug. 13 3.74 93 1976 July 8 3.98 127 1986 Nov. 22 5.20 492 102 SANTEE RIVER BASIN 02172500 SOUTH FORK EDISTO RIVER NEAR MONTMORENCI, S.C. LOCATION.--Lat 33'3413511, long 81*30,5011, Aiken County, Hydrologic Unit 03050204, near center of span on downstream side of bridge on State Highway 215, 0.4 mi upstream from Cedar Creek, 1 mi upstream from Shaw Creek, and 7.6 mi northeast of Montmorenci. DRAINAGE AREA.--198 mi2. PERIOD OF RECORD.--October 1939 to September 1966; October 1971 to current year. GAGE.--Water-stage recorder prior to September 1966. Crest-stage gage thereafter. Datum of gage is 250.18 ft National Geodetic Vertical Datum of 1929 (levels by Corps of Engineers). Prior to Oct. 29, 1954, wire- weight gage at same site and datum. REMARKS.--Records good prior to June 30, 1955, and fair thereafter. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 5,010 ft 3/s, Aug. 31, 1964, gage height, 10.24 ft. STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 4,490 fts/s and graphically extended on logarithmic plotting paper. FLOOD-FREQUENCY DATA (fts /S) LOG-PEARSON TYPE III STATISTICS (LOG UNITS) 44 YEARS OF RECORD Mean = 3.193 LOG-PEARSON TYPE III Standard Deviation - 0.210 Q = 1 570 Weighted Skew - -0.101 2 = '350 Q5 2, Q10 = 2,880 Q25 = 3,580 = 4,100 Q50 4,640 Q100 = Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height 3 year height a year height 3 (ft) (ft /s) (ft) (ft /s) (ft) (ft IS) 1940 Aug. 15 8.81 2,460 1955 Apr. 16 8.16 1,790 1975 July 17 9.03 2,700 1941 July 19 8.81 2,460 1956 Apr. 13 6.75 755 1976 June 29 7.92 1,550 1942 Mar. 10 7.88 1,650 1957 May 14 6.90 750 1977 Dec. 19 8.53 2,120 1943 Mar. 23 7.98 1,740 1958 Apr. 18 7.82 1,560 1978 Jan. 28 8.75 2,360 1944 Mar. 24 8.71 2,370 1959 May 10 8.33 1,990 1979 Feb. 24 8.45 2,040 1945 Apr. 27 6.97 898 1960 Oct. 1 9.57 3,120 1980 Mar. 13 8.18 1,780 1946 Apr. 19 6.73 898 1961 Feb. 26 9.15 2,690 1981 Feb. 18 6.78 738 1947 Oct. 10 7.47 1,320 1962 Feb. 24 8.83 2,540 1982 Jan. 6 7.98 1,600 1948 Mar. 9 7.62 1,400 1963 Jan. 22 7.46 1,160 1983 Apr. 11 9.36 3,210 1949 Aug. 30 8.52 2,180 1964 Aug. 31 10.24 5,010 1984 Feb. 29 7.50 1,190 1950 Sept. 9 6.86 685 1965 Dec. 28 8.85 2,470 1985 Feb. 7 8.28 1,870 1951 Apr. 5 6.71 615 1966 June 12 8.00 1,620 1986 Nov. 22 7.62 1,290 1952 Mar. 6 8.21 2,040 1972 Jan. 14 8.20 1,780 1987 Mar. 1 7.25 1,020 1953 May 8 7.62 1.400 1973 Feb. 2 7.73 1,380 1988 Sept. 9 6,79 744 1954 Dec. 15 7.07 858 1974 Jan. 3 7.13 948 103 EDISTO RIVER BASIN 02173000 SOUTH FORK EDISTO RIVER NEAR DENMARK, S.C. LOCATION.--Lat 33'23'3511, long 81*08100", Orangeburg County, Hydrologic Unit 03050204, on left bank at downstream side of bridge on U.S. Highway 321, 360 ft downstream from Seaboard Coast Line Railroad Bridge, 1.8 mi downstream from Little River, 4.8 mi north of Denmark, and at mile 136.6. DRAINAGE AREA.--720 mi2. PERIOD OF RECORD.--August 1931 to current year. GAGE.--Continuous water-stage recorder prior to September 1971; crest-stage gage 1972 to 1980; continuous recorder thereafter. Datum of gage is 155.68 ft National Geodetic Vertical Datum of 1929 (levels by Corps of Engineers). Prior to Oct. 27, 1931, nonrecording gage at same site and datum. REMARKS.--Records good. EXTREMES FOR PERIOD OF RECORD. --Maximum discharge, 13,500 fts/s, Apr. 11, 1936, gage height, 10.91 ft. EXTREMES OUTSIDE PERIOD OF RECORD.--Maximum flood known since at le5st 1893, 11.7 ft in October 1929, on basis of information from State Highway Department (discharge 17,100 ft /s, by convey anc e-s lope study). STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 7,020 fts/s and extended on the basis of velocity-area studies. FLOOD-FREQUENCY DATA (ft3 /s) LOG-PEARSON TYPE III STATISTICS (LOG UNITS) 56 YEARS OF RECORD Mean - 3.425 LOG-PDNffTN_TY_PE III Standard Deviation - 0.202 Q2 = 2,540 Weighted Skew . 0.581 Q5 = 31860 Q10 = 41920 Q25 - 6.520 Q50 - 7 920 Q100 9:490 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height 3 year height 3 year h7ight (ft3/s) (ft) (ft /s) (ft) (ft /5) ft) 1930 Oct. -- 11.70 17,100 1951 Apr. 2 6.97 1,320 1971 Mar. 5 8.64 4,820 1932 Aug. 12 8.47 2,930 1952 Mar. 26 7.59 2,390 1972 Jan. 18 7.74 2,750 1933 Nov. 4 8.07 2,290 1953 Sept,29 7.56 2,500 1973 Feb. 3 8.01 3,270 1934 June 5 8.51 2,850 1954 Dec. 16 7.25 1,750 1974 Feb. 19 7.36 2,130 1935 Aug. 22 8.36 2,640 1955 Apr. 20 7.19 1,640 1975 July 19 8.08 3,420 1936 Apr. 11 10.91 13,500 1956 Feb. 8 6.91 1,350 1976 June 30 7.19 1,880 1937 Oct. 14 8.03 2,260 1957 Mar. 27 6.70 1,030 1977 Dec. 19 7.84 2,940 1938 Apr. 10 8.20 2,470 1958 Apr. 17 8.00 3,210 1978 Jan. 28 7.63 2,560 1939 Mar. 3 9.05 4,860 1959 May 14 7.70 2,810 1979 Feb. 24 8.03 3,310 1940 Aug. 19 7.92 2,060 1960 Apr. 6 8.75 5,150 1980 1941 July 22 7.91 2,060 1961 Apr. 17 8.22 3,780 1981 Feb. 18 6.98 1,560 1942 Dec. 26 8.06 2t840 1962 Feb. 27 7.80 3,110 1982 Jan. 6 7.41 2,200 1943 Mar. 24 7.62 2,080 1963 Jan. 22 7.67 2t710 1983 Apr. 13 7.80 2,870 1944 Mar. 25 8.24 3,220 1964 Sept. 2 9.41 7,350 1984 May 8 7.90 3,050 1945 Sept.19 8.32 3,310 1965 Oct. 20 8.18 3,610 1985 Feb. 8 7.68 2,850 1946 Jan. 1 7.40 1,740 1966 Mar. 5 8.28 3,820 1986 Nov. 23 6.84 2,000 1947 Aug. 15 2,040 1967 Aug. 28 7.91 3,070 1987 Jan. 24 7.73 2,650 1948 Feb. 14 8.38 4,010 1968 June 13 7.46 2,490 1988 Jan. 24 6.42 904 1949 Oct. 5 8.30 3,810 1969 Apr. 20 8.10 3,460 1950 Mar. 9 6.89 1,210 1970 Apr. 1 7.58 2,480 104 EDISTO RIVER BASIN 02173500 NORTH FORK EDISTO RIVER AT ORANGEBURG, S.C. LOCATION.--Lat 33*2910011, long 80*5212511, Orangeburg County, Hydrologic Unit 03050203, on left bank under bridge on U.S. Highway 301 at Orangeburg, 0.5 mi upstream from Seaboard Coast Line Railroad bridge, 1.5 mi downstream from Caw Caw Swamp and at mile 22.1. DRAINAGE AREA.--683 m12. REVISED RECORDS.--WSP 1032: Drainage area. PERIOD OF RECORD.--October 1938 to current year. Monthly discharge only for some periods, published in WSP 1303. GAGE.--Water-stage recorder. Datum of gage is 149.02 ft National Geodetic Vertical Datum of 1929 (levels by Corps of Engineers). Prior to Feb. 23, 1939, nonrecording gage at same site and datum. REMARKS.-- ,Records good. About 7.4 ft3/s, diverted by City of Orangeburg for municipal supply. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 9,500 ft3/s, Sept. 18, 1945, gage height, 14.28 ft. EXTREMES OUTSIDE PERIOD 0; RECORD.--Maximum flood known since at least 1893, 14.7 ft in September 1928, discharge, 10,000 ft /a, from rating curve extended as described below, on basis of information from Department of Public Utilities, City of Orangeburg. STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 5,230 ft3/s and extended by velocity-area studies. FLOOD-FREQUENCY DATA (ft3/S) LOG- 51 YEARS OF RECORD Mean 3.422 LOG-PEARSON TYPE III Standard Deviation 0.199 QQ2 = 2,590 Weighted Skew 0.277 5 = 31860 Q 4,820 Q'0 61150 25 7,240 Q50 Q100 8,420 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height 3 year height year height (ft) (ft Is) (ft) (ft3 /a) (ft) (ft 3/s) 1928 Sept.-- 14.70 10,000 1955 Apr. 20 7.78 1,420 1972 Jan. 16 9.40 2,990 1939 Mar. 3 9.98 3,910. 1956 Feb. 8 7.44 1,160 1973 June 13 10.01 3,730 1940 Aug. 19 8.59 2,340 1957 June 17 7.62 1,250 1974 Aug, 11 8.14 1,880 1941 June 29 11.00 5,210 1958 May 1 9.73 3,340 1975 July 21 8.94 2,530 1942 Dec. 26 8.96 2t670 1959 May 14 8.80 2,570 1976 July 1 9.19 2,760 1943 Mar. 24 8.20 1,930 1960 Apr. 6 10.36 4,240 1977 Dec. 17 9.02 2,600 1944 Mar. 25 8.90 2,620 1961 Apr. 17 9.61 3,340 1978 Jan. 26 9.22 2,790 1945 Sept.18 14.28 9,500 1962 Feb. 24 9.21 2,770 1979 Sept. 6 11.56 5,720 1946 Jan. 1 7.90 1,670 1963 Jan. 22 9.26 2,880 1980 Mar. 31 9.23 2,800 1947 Apr. 18 8.16 1,880 1964 Aug. 31 11.34 5,410 1981 Oct. 2 7.38 1,410 1948 Sept. 7 10.25 1965 Oct. 6 11.05 5,080 1982 Jan. 6 8.10 1,850 1949 Aug. 29 10.47 4,560 1966 Mar. 6 9.79 3,450 1983 Apr. 13 9.04 2,610 1950 Sept.10 8.03 1,800 1967 Aug. 29 9.00 2,570 1984 May 30 10.00 3,720 1951 Apr. 10 7.50 1,370 1968 June 12 8.65 2,240 1985 Feb. 8 8.78 2,380 1952 Mar. 25 8.54 2,410 1969 Apr. 21 8.60 2,200 1986 Nov. 23 8.23 1,940 1953 Sept.29 8.43 2,160 1970 Apr. 2 8.71 2,300 1987 Jan. 24 8.88 2,470 1954 Apr. 10 7.79 1,550 1971 Mar. 5 11.64 5,850 1988 Mar. .13 6.50 1,050 105 EDISTO RIVER BASIN 02174000 EDISTO RIVER NEAR BRANCHVILLE, S.C. LOCATION.--Lat 33*10135", long 80*45'05", Bamberg County, Hydrologic Unit 03050205, on right bank 400 ft downstream from bridge on U.S. Highway 21, 4.7 mi downstream from Brier Branch, 5.2 mi south of Branchville, and at mile 100.0. DRAINAGE AREA.--1,720 mi 2, approximately. PERIOD OF RECORD.--October 1945 to current year. Monthly discharge only for some periods, published in WSP 1303. GAGE.--Water-stage recorder. Datum of gage is 80,02 ft National Geodetic Vertical Datum of 1929 (levels by Corps of Engineers). Prior to May 19, 1949, at datum 1.00 ft higher. REMARKS.--Records good. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 14,600 ft3/s, Sept. 3, 1964, gage height, 11.44 ft. EXTREMES OUTSIDE PERIOD OF RECORD.--Maximum flood known since at least 1893, 13.5 ft, @resent datum, in September 1928, on basis of information from State Highway Department, discharge, 25,700 ft /a, by conveyance-s lope study. STAGE-DISCHARGE RELATION.--Defined by current-meter measurements below 13,800 ft 31s and graphically extended on logarithmic plotting paper. FLOOD-FREQUENCY DATA (ft3 /s) LOG-PEARSON TYPE III STATISTICS (LOG UNITS1 44 YEARS OF RECORD Mean - 3.768 LOG-PEARSON TYPE III Standard Deviation - 0.210 Q = 5,890 Weighted Skew = -0.057 Q 2 = 81820 5 = 10,900 Q10 Q = 13.500 Q 25 = 15 600 Q50 I 100 = 17,700 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height 3 year height year height (ft) (ft /s) (ft) (ft 3/a) (ft) (ft 3/a) 1928 Sept.-- 14.50 25,700 1960 Apr. 8 10.93 12,600 1975 July 22 8.88 6,060 1946 Jan. 4 8.75 4,100 1961 Apr. 19 9.97 9,190 1976 June 30 9.08 6,460 1947 Apr. 18 8.23 4,870 1962 Mar. 3 9.04 6,490 1977 Dec. 20 8.73 5,760 1948 Apr. 4 10.95 9,140 1963 Jan. 26 8.97 6,490 1978 Jan, 28 9.64 7,750 1949 Oct. 6 11.21 10,000 1964 Sept. 3 11.44 14,600 1979 Sept. 8 9.81 8,210 1950 Mar. 12 6.22 2,540 1965 Oct. 19 10.57 10,700 1980 Mar. 16 9.62 7,730 1951 Apr. 3 7.36 3,640 1966 Mar. 8 10.06 8,910 1981 Feb. 22 6.95 3,200 1952 Mar. 29 8.47 5,350 1967 Sept. 1 7.69 4,260 1982 Jan. 9 8.14 4,700 1953 Mar. 3 8.27 4,950 1968 June 16 8.10 4,240 1983 Apr. 16 8.91 6,120 1954 Oct. 3 6.79 3,030 1969 May 21 8.86 5,630 1984 May 9 10.02 8,770 1955 Apr. 24 6.43 2,690 1970 Apr. 3 9.17 6,380 1985 Feb. 11 8.61 5,350 1956 Feb. 11 3,030 1971 Mar. 8 10.68 11,100 1986 Nov. 24 8.82 5,730 1957 Mar. 31 5.63 2,200 1972 Feb. 6 9.09 6,480 1987 Mar. 4 8.90 5,900 1958 Apr. 19 8,050 1973 June 17 10.12 9,120 1988 Mar. 17 5.62 2,150 1959 Mar. 9 8.36 5,150 1974 Feb. 20 8.57 5,440 106 EDISTO RIVER BASIN 02174250 COW CASTLE CREEK NEAR BOWMAN, S.C. LOCATION.--Lat 33*22'43", long 80*42'00", Orangeburg County, Hydrologic Unit 03050206, at bridge on county road, 1.1 mi above Buck Branch and 3.2 mi northwest of Bowman. DRAINAGE AREA.--23.4 mi 2. PERIOD OF RECORD.--October 1970 to September 1980. GAGE.--Water-stage recorder. Elevation of gage is 125 ft (from topographic map). REMARKS.--Records good. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 2,340 ft3/s probably occurred Sept. 4 or 5, 1979, gage height, 7.37 ft from recorded range in stage.. STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 830 ft3/s and graphically extended on logarithmic plotting paper. FLOOD-FREQUENCY DATA (ft3 /a) LOG-PEARSON TYPE III STATISTICS (LOG UNITS) 10 YEARS OF RECORD Mean - 2.557 LOG-PEARSON TYPE III Standard Deviation - 0.338 Q2 = 436 Weighted Skew = 0.307 Q5 = 8@61 Q = 1,260 Q10 = 1,920 Q25 = 2,540 50 = 3,290 Q100 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height 3 year height 3 year height 3 (ft) (ft /a) (ft) (ft /a) (ft) (ft /a) 1971 Mar. 4 6.36 466 1975 Feb. 20 5.76 267 1979 Sept. 4 7.37 2,340 1972 Feb. 4 5.64 188 1976 July 7 5.87 292 1980 Mar. 13 6.34 493 1973 June 12 6.83 1,290 1977 Mar. 22 5.92 306 1974 Feb. 17 5.95 278 1978 Jan. 26 6.25 430 107 EDISTO RIVER BASIN 02175000 EDISTO RIVER NEAR GIVHANS, S.C. LOCATION.--Lat 33*01'40", long 80*23'30", Dorchester County, Hydrologic Unit 03050205, an left bank at downstream side of bridge on State Highway 61, 2.3 mi downstream from Four Hole Swamp, 2.8 mi west of Givhans, and at mile 59.9, DRAINAGE AREA.--2,730 m12, approximately. PERIOD OF RECORD.--January 1939 to current year. REVISED RECORDS.--WSP 1032: Drainage area. WSP 1303: 1939 (monthly and yearly runoff). GAGE.--Water-stage recorder. Datum of gage is 20.46 ft National Geodetic Vertical Datum of 1929. REMARKS. --Records good. About 112 ft3/s a day diverted above station for Charleston water supply during year. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 24,500 ft3/s, June 14, 1973, gage height, 15.84 ft. EXTREMES OUTSIDE PERIOD OF RECORD.--Maximum stage known since at least 1904, 17 5 ft in February 1925, from investigation by Charleston Commissioners of Public Works, discharge, 24,960 ft3/s. STAGE-DISCHARGE RELATION.--Defined by current-meter measurements below 24,500 ft3/s. FLOOD&EOUENC11 DATA (ft3/s) 52 YEARS OF RECORD Mean . 3.989 LOG-PEARSON TYPE III Standard Deviation - 0.231 02 10,100 Weighted Skew - -0.397 Q 5 15,400 Q10 18,800 22 900 25 25:900 050 28,700 0100 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height year height year height (ft) (ft3/5) (ft) (ft3 /a) ft) (ft3/s) 1904 Aug. -- 17.00 1954 Jan. 6 7.91 3,610 1974 Feb. 22 12.56 9,800 1919 July 31 14.00 1955 Sept.16 8.81 4,540 1975 Feb. 26 12.52 9,690 1924 Sept.-- 15.50 1956 Feb. 14. 9.54 5,440 1976 July a 12.63 9,980 1925 Feb. -- 17.50 24,900 1957 May 21 7.89 3,610 1977 Dec. 19 12,06 8,610 1928 Sept.11 15.70 19,500 1958 Apr, 22 13.13 12,000 1978 Feb. 2 12.80 10,400 1939 Mar. 6 14.68 16,900 1959 Mar. 9 13.90 14,100 1979 Sept. 9 15.51 22,400 1940 Aug. 15 13.03 12,600 1960 Apr. 11 14.29 14,600 1980 Mar. 19 13.99 14,700 1941 July 5 12.64 10,800 1961 Apr. 20 14.05 14,100 1981 Feb. 26 7.61 3,030 1942 Dec. 30 13.48 13,100 1962 Mar. 6 12.41 10,200 1982 Jan. 9 11.46 7,490 1943 Mar. 30 11.32 8,010 1963 Jan. 29 11.80 8,060 1983 Mar. 22 13.84 14,000 1944 Mar. 30 13.44 13,100 1964 July 29 15.12 19,800 1984 May 12 13.92 14,300 1945 Sept.21 17.28 24,300 1965 Oct. 21 15.14 19,900 1985 Feb. 17 9.94 5,200 1946 Jan. 24 11.58 8,940 1966 Mar. 11 13.63 13,100 1986 Dec. 19 12.60 9,940 1947 Apr. 22 11.38 8,540 1967 Jan. 13 9.83 4,910 1987 Mar. 8 12.70 10,200 1948 Apr. 6 14.38 15,200 1968 June 20 10.07 5,250 1988 Sept.18 7.78 3,150 1949 Dec. 3 14.62 15,800 1969 May 26 12.93 10,800 1950 Sep. 12 8.66 4,090 1970 Apr. 6 13.07 11,200 1951 Apr. 9 9.21 4,790 1971 Mar. 11 13.90 14,200 1952 Apr. 2 11.27 7,950 1972 Feb. 7 13.10 11,300 1953 Mar. 7 12.26 10,400 1973 June 14 15.84 24,500 108 COMBAHEE RIVER BASIN 02175450 SAVANNAH CREEK NEAR EHRHARDT, S.C. LOCATION.--Lat 33*02'03'', long 81*03'11", Colleton county, Hydrologic Unit 03050207, on upstream side of culvert on State Highway 641, 1.2 mi upstream from Salkshatchie River, and 6.0 mi north of Miley. DRAINAGE AREA.--12.4 mi2. PERIOD OF RECORD.--December 1974 to current year. GAGE.--Dual digital water-stage and rainf all recorders, September 1967 to October 1974. Partial record crest &age from December 1974 to current year. REMARKS.--Records good. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 895 ft3/s, March 13, 1980, gage height, 8.30 ft. STAGE-DISCHARGE RELATION. --Defined by current-motor measurements below 211 ft3/s and graphically extended on logarithmic plotting paper. FLOOD-FREQUENCY DATA (ft3/s) LOG-PEARSON TYPE III STATISTICS (LOG UNITS) 12 YEARS OF RECORD Mean - 2.472 LOG-PEARSON TYPE III Standard Deviation = 0.213 Q2 291 Weighted Skew = 0.221 Q5 445 Q 561 Q 10 79-4 Q 25 858 50 1,000 Q100 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height year height year height ft) (ft3/.) (ft) (ft 3/s) (ft) (ft3 /a) 1977 June 20 6.53 324 1981 Oct. 1 5.86 230 1985 Feb. 7 5.29 160 1978 Jan. 25 6.69 347 1982 Jan. 5 5.38 170 1986 Dec. 14 7.12 400 1979 Apr. 26 6.80 362 1983 Feb. 17 5.89 236 1987 Mar. 1 6.58 333 1980 Mar. 13 8.30 895 1984 May 13 7.04 395 1988 Sept.12 5.33 164 @109 COMBAHEE RIVER BASIN 02175500 SALKEHATCHIE RIVER NEAR MILEY, S.C. LOCATION.--Lat 32*59'20", long 81*03'10", Hampton County, Hydrologic Unit 03050207, on right bank 90 ft downstream from bridge on U.S. Highway 601, 2.4 mi downstream from Savannah Creek, 3.1 mi upstream from Hampton and Branchville Railroad bridge, 3.1 mi northwest of Miley, and at mile 68.0. DRAINAGE AREA.--341 m12. PERIOD OF RECORD.--February 1951 to current year. GAGE.--Water-stage recorder. Datum of gage is 64.35 ft National Geodetic Vertical Datum of 1929. Dec. 6, 1957 to Jan. 22, 1971, nonrecording gage at same site and datum. Prior to Dec. 6, 1957, nonrecording gage at bridge 90 ft upstream at same datum. REMARKS.--Records good. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 3,300 fts/s, Mar. 13, 1980, gage height, 5.44 ft STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 2,010 fts/s and graphically extended on logarithmic plotting paper. FLOOD-FREQUENCY DATA (ft3 /s) LOG-PEARSON TYPE III STATI@TICS (JL70G UNITS) 38 YEARS OF RECORD Mean 3. 2 LOG-PEARSON TYPE III Standard Deviation = 0.183 Q2 - 1.490 Weighted Skew = -0.059 Q5 = 2,120 Q20 = 2 550 Q25 - 3:080 Q = 3,490 50 = 3,890 Q100 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height year he year height 3 3 (ight (ft) (ft /a) (ft) (ft /s) ft ) (ft3/8) 1951 Apr. 2 3.92 774 1966 Mar. 6 5.00 2,200 1981 Oct. 2 3.88 771 1952 Mar. 28 4.02 905 1967 Mar. 13 4.60 1,740 1982 Jan. 5 4.27 1,110 1953 Sept.30 4.04 950 1968 June 13 4.32 1,340 1983 Feb. 17 4.19 1,140 1954 May 15 3.87 860 1969 May 20 4.90 2,200 1984 May 9 4.90 2,200 1955 Apr. 15 4.02 950 1970 Apr. 2 4.57 1,700 1985 Feb. 9 4.07 985 1956 May 6 3.99 774 1971 Mar. 4 4.48 1,570 1986 Dec. 14 5.35 2,850 1957 Mar. 26 3.68 732 1972 Feb. 4 2,000 1987 Mar. 2 4.77 1,840 1958 Apr. 17 4.21 1,140 1973 June 20 4.93 2,240 1988 Sept.12 4.19 1,070 1959 Mar. 7 4.61 1,600 1974 Feb. 18 4.53 1,650 1960 Apr. 6 4.94 1,880 1975 July 20 5.00 2,350 1961 Apr. 17 4.48 1,390 1976 July 7 4.83 2,100 1962 Mar. 15 4.33 1,200 1977 Mar. 24 4.34 1,480 1963 Jan. 23 4.24 1,100 1978 Jan. 28 4.63 1,800 1964 Sept. 2 4.99 2,340 1979. Sept, 6 5.34 3,050 1965 Oct. 17 5.06 2,230 1980 Mar. 13 5.44 3,300 110 COMBAHEE RIVER BASIN 02176000 COMBAHEE RIVER NEAR YEMASSEE, S.C. LOCATION.--Lat 32'42'25", long 80*4913511, Hampton County, Hydrologic Unit 03050208, near left bank on downstream side of pile bent on bridge on U.S. Highway 17A, 0.2 mi upstream from Atlantic Coast Line Railroad bridge, 1.8 mi northeast of Yemassee, and 5 mi downstream from Black Creek. DRAINAGE AREA.--1,100 m12. PERIOD OF RECORD.--October 1952 to September 1966. GAGE.--Recording prior to June 30, 1957; crest-stage gage thereafter. Datum of gage is at National Geodetic Vertical Datum of 1929. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 11,700 ft 3/s July 22, 1964, gage height 10.87 ft. STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 3,910 fts/s and extended on the basis of velocity-area studies. FLOOD-FREQUENCY DATA (ft3 /s) LOG-PEARSON TYPE III STATISTICS (LOG UNITS) 15 YEARS OF RECORD Mean . 3.744 LOG-PEARSON TYPE III Standard Deviation - 0.225 Q2 6,050 Weighted Skew - -0.223 Q5 91230 Q10 11,400 Q25 14 100 Q50 16:200 Q100 18,200 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year hzight (ft3/s) year height year height ft) (ft) (ft3 /a) (ft) (ft3/a) 1952 Feb. 19 7.51 3,530 1957 June 6 6.71 2,150 1962 Mar. 17 8.50 5,630 1953 Mar. 8 7.32 3,110 1958 Apr. 19 9.22 7,930 1963 Jan. 25 8.39 5,410 1954 May 18 7.51 3,530 1959 Mar. 7 10.16 9,850 1964 July 22 10.87 11,700 1955 Apr. 18 8.18 5,330 1960 Nov. 2 10.80 11,400 1965 Oct. 16 10.62 10,900 1956 Feb. 10 7.96 4,680 1961 Apr. 20 9.22 7,350 1966 Mar. 8 9.29 7,600 BROAD RIVER BASIN 02176500 COOSAWRATCHIE RIVER NEAR HAMPTON, SC LOCATION.--Lat 32*5011011, long 81*0715511, Hampton County, Hydrologic Unit 03050208, near left bank on downstream side of bridge on U.S. Highway 601, 1.6 mi downstream from Black Creek, 2.5 mi southwest of Hampton, and at mile 33.6. DRAINAGE AREA.--203 m12. PERIOD OF RECORD.--February 1951 to current year. GAGE.--Water-stage recorder. Datum of gage is 50.30 ft above National Geodetic Vertical Datum of 1929. Prior to Oct. 26, 1954, nonrecording gage at same site and datum. REMARKS.--Records good. EXTREMES FOR PERIOD OF RECORD. --Maximum discharge, 8,160 ft3/s, Sept. 2, 1969, gage height, 8.39 ft, from floodmarks. STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 6,300 fts/s and graphically extended on logarithmic plotting paper. FLOOD-FREQUENCY DATA.(ftl/s) LOG-PEARSON TYPE III STATISTICS (LOG UNITS) 38 YEARS OF RECORD Mean - 3.229 LOG-PEARSON TYPE III Standard Deviation - 0.246 Q2 = 1,680 Weighted Skew - 0.067 Q 5 = 21720 Q10 = 31510 Q25 = 4,620 Q = 5 530 50 - 6:500 Q100 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height year height 3 year height 3 (ft3/s) (ft) (ft /s) (ft) (ft /s) ft) 1951 Apr. 1 4.82 1,220 1966 Mar. 5 5.65 2,370 1981 Apr. 3 4.09 585 1952 Feb. 16 5.20 1,780 1967 Aug. 12 4.53 974 1982 July 18 4.55 989 1953 Mar. 24 5.78 2,750 1968 June 9 3.89 416 1983 Mar. 8 5.18 1,620 1954 May 16 5.45 2,360 1969 Sept. 2 8.39 8,160 1984 July 31 4.84 1,190 1955 Apr. 15 5.05 1,430 1970 Mar. 31 5.66 2,120 1985 Aug. 31 4.65 1,000 1956 Feb. 7 4.98 1,390 1971 Mar. 4 5.16 1,530 1986 Nov. 23 5.80 2,440 1957 May 31 4.26 649 1972 Feb. 4 5.23 1,660 1987 Mar. 2 5.50 2,030 1958 Apr. 16 5.07 1,400 1973 June 14 5.47 1,940 1988 Sept.10 4.85 1,200 1959 Mar. 6 5.87 2,950 1974 Feb. 9 5.11 1,520 1960 Jan. 31 5.48 2,150 1975 July 19 5.61 2,150 1961 Apr. 17 5.16 1,580 1976 July 7 5.29 1,760 1962 Mar. 12 1,250 1977 Mar. 8 4.57 1,030 1963 Jan. 29 5.61 2,190 1978 Jan. 27 5.03 1,460 1964 Aug. 30 6.21 3,720 1979 Sept, 6 5.66 2,210 1965 Oct. 16 6.27 3,880 1980 Mar. 14 7.09 4,800 112 SAVANNAH RIVEP BASIN 02184500 WHITEWATER RIVER AT JOCASSEE, S.C. LOCATION.--Lat 34*58'19", long 82'56124", Oconee County, Hydrologic Unit 03060101, on right bank at highway bridge at Jocassee, 0.8 mi upstream from confluence with Toxaway River. DRAINAGE AREA.--47.3 m12. PERIOD OF RECORD.--January 1951 to April 1958. GAGE.--Water-stage recorder. Datum of gage is 777.79 ft National Geodetic Vertical Datum of 1929. REMARKS.--Records fair. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 6,900 ft3/s, Oct. 4, 1964, gage height, 14.30 ft. STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 1,540 ft3/s and extended an the basis of indirect computations of peak discharge using the width contraction method. FLOOD-FREQUENCY DATA (ft31s) LOG-PEARSON TYPE III STATISTICS (LOG UNITS1 16 YEARS OF RECORD Mean = 3,505 LOG-PEARSON TYPE III Standard Deviation = 0.180 Q2 = 31120 Weighted Skew - 0.343 Q5 = 41490 Q - 5 510 Q10 6:920 Q25 8 060 50 9:290 Q100 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height year height year height (ft) (ft3 /5) (ft) (ft3/3) (ft) (ft3/s) 1952 Mar.'11 11.17 5,280 1957 Apr. 4 6.31 2,710 1962 Dec. 12 7.00 3,100 1953 Feb. 21 6.53 2,820 1958 Dec. 20 2,410 1963 Mar. 6 5.78 2,370 1954 Jan. 22 6.38 2,730 1959 May 31 1,990 1964 Sept.29 12.48 5,990 1955 Feb. 6 2.260 1960 Oct. 9 2,340 1965 Oct. 4 14.30 6,900 1956 Apr. 15 5.10 1,950 1961 Feb. 25 6.65 2,890 1966 Oct. 1 11.20 5,350 1967 June 4 9.76 4,630 113 SAVANNAH RIVER BASIN 02185000 KEOWEE RIVER NEAR JOCASSEE, S.C. LOCATION.--Lat 34*57121", long 82*54141", Oconee County, Hydrologic Unit 03060101, on right bank 0.6 mi downstream from bridge on State Highway 11, 1.8 mi southeast of Jocassee, and 2.6 mi upstream from Eastatoe Creek. DRAINAGE AREA.--148 m12. PERIOD OF RECORD.--December 1949 to April 1968. GAGE.--Water-stage recorder. Datum of gage is 737.43 ft National Geodetic Vertical Datum of 1929. REMARKS.--Records good. EXTREMES FOR PERIOD OF RECORD. --Maximum discharge, 21,000 ft3/s, Oct. 4, 1964, gage height, 22.03 ft. STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 8,480 ft3/s and extended on the basis of indirect computations of peak discharge using the slope-area method. FLOOD-FREQUENCY DATA (ft3/5) LOG-PEARSON-TYPE III STATISTICS (LOG UNITS) 18 YEARS OF RECORD Mean - 3.984 EO-G-PEARSON TYPE III Standard Deviation - 0.182 Q2 = 9,500 Weighted Skew = 0.215 Q 5 = 13,700 Ql - 16,700 Q25 = 20,700 Q50 = 24 000 Q100 = 27:400 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height year height year height 3 3 3 (ft) (ft /s) (ft) (ft /5) ft) (ft /s) 1950 Sept. 1 11.46 11,800 1956 Apr. 16 6.74 5,780 1962 Dec. 12 10.45 10,400 1951 Dec. 7 8.29 7,700 1957 Apr. 4 9.03 8,540 1963 Mar. 6 6,620 1952 Mar. 11 16.23 16,200 1958 Dec. 20 7.08 6.260 1964 Sept.29 17.84 17,700 1953 Feb. 21 10.03 9,840 1959 Apr. 12 6.85 5,900 1965 Oct. 4 22.03 21,000 1954 Jan. 22 9.49 9,190 1960 Feb. 5 6.52 5,540 1966 Mar. 13 16.07 16,100 1955 Feb. 6 7.77 7,100 1961 Feb. 25 9.67 9,450 1967 June 4 14,12 14,100 114 SAVANNAH RIVER BASIN 02185200 LITTLE RIVER HEAR WALHALLA, S.C. LOCATION.--Lat 34*50111", long 82*58'4811, Oconee County, Hydrologic Unit 03060101, at downstream side of bridge on State Road 24, 0.5 mi downstream from Oconee Creek, 3.5 mi south of Salem and 6.5 mi northeast of Walhalla. DRAINAGE AREA.--72.0 m12. PERIOD OF RECORD.--March 1967 to current year. GAGE.--Water-stage recorder. Datum of gage is 807.63 ft National Geodetic Vertical Datum of 1929. REMARKS.--Records good. EXTREMES FOR PERIOD OF RECORD.--- Maximum discharge, 12.800 ft3/s, June 4, 1967, gage height, 12.29 ft. STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 3,050 ft3js and graphically extended on logarithmic plotting paper. FLOOD-FREOUENCY DATA (ft3/s) LOG-PEARSON TYPE III STATISTICS (LOG UNITS) 21 YEARS OF RECORD Mean - 3.560 LOG-PEARSON TYPE III Standard Deviation - 0.322 Q2 = 3,640 Weighted Skew - -0.033 Q - 61790 5 = 91370 Q10 13.200 Q2' : 16,400 Q50 = 20,000 Q100 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height year height year height (ft) (ft 3 /s) (ft) (ft3/s) (ft) (ft3/s) 1967 12.29 12,800 1977 Mar. 30 7.55 5,700 1987 Nov. 26 7.97 5,890 1968 6.29 4,400 1978 Jan. 25 6.66 4,450 1988 Jan. 20 4.08 1,660 1969 Aug. 22 5.42 3,340 1979 June 8 7.93 5,400 1970 Nov. 1 3.38 1,260 1980 Nov. 2 7.22 4,750 1971 Jan. 5 3.37 1,260 1981 Mar. 30 2.96 860 1972 Dec. 7 5.73 3,300 1982 Feb. 3 6.31 3,750 1973 May 28 11.39 12,300 1983 May 20 4.19 1,750 1974 Dec. 26 4.56 2,050 1984 1975 Mar. 14 6.45 4,160 1985 Aug. 17 5.90 3,400 1976 May 29 10.30 10,100 1986 Nov. 1 6.43 115 SAVANNAH RIVER BASIN 02185500 SENECA RIVER NEAR NEWRY, S.C. LOCATION.--Lat 34'4410911, long 82*5211911, Oconee County, Hydrologic Unit 03060101, on left bank 800 ft downstream from Lawrence Bridge, 0.7 mi upstream from Sixmilo Creek, and 2.2 mi east of Newry. DRAINAGE AREA.--455 m12. PERIOD OF RECORD.--October 1939 to June 1961. Prior to October 1960, published as Keowee River near Newry. GAGE.--Water-stage recorder. Datum of gage is 625.00 ft National Geodetic Vertical Datum of 1929. REMARKS.--Records good prior to Apr. 22, 1961 fair thereafter. Some regulation at low flow by powerplant above station. Stage-discharge relation affected by backwater from construction of Hartwell Reservoir subsequent to Apr. 21. EXTREMES FOR PERIOD OF RECORD. --Maximum discharge, 25,200 ft3/s, Aug. 13, 1940; may'rm gage height, 24.60 ft. STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 19,300 ft3/s and graphically extended on logarithmic plotting paper. FLOOD-FREQUENCY DATA (ft3/s) LOG-PEARSON TYPE III STATISTICS CLOG UNITS) 22 YEARS OF RECORD Mean - 4.215 LOG-PEARSON TYPE III Standard Deviation - 0.105 Q2 - 16,600 Weighted Skew - -0.247 Q = 20,100 Q5 - 22,200 10 Q215 ' 24,500 Q50 26,000 Q100 = 27,500 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height year height year height 3 (ft) (ft3/s) (ft) (ft3ls) (ft) (ft /6) 1940 Aug. 13 24.60 25,200 1950 Oct. 7 22.69 21,100 1960 Mar. 30 15.92 13,300 1941 July 7 13.27 10,400 1951 Dec. 7 15.97 13,000 1961 June 22 20.94 20,200 1942 Feb. 17 20.28 18,900 1952 Mar. 11 23.16 22,000 1943 Dec. 29 17plOO 1953 Feb. 21 18.89 26,300 1944 Mar. 20 17.01 14,900 1954 Jan. 22 19,700 1945 Feb. 22 8.25 5,530 1955 Feb. 6 17,500 1946 Jan. 7 21.32 20,300 1956 Apr. 16 17.32 14,900 1947 Jan. 20 16.26 13,900 1957 Apr. 5 20.32 18,300 1948 Aug. 4 19.09 17,500 1958 Nov. 19 13.72 10,800 1949 Nov. 29 20.54 19,000 1959 Apr. 12 17.-Ol 14,400 116 SAVANNAH RIVER BASIN 02186000 TWELVEMILE CREEK NEAR LIBERTY, S.C. LOCATION.--Lat 34*4810511, long 82*44,5511, Pickens County, Hydrologic Unit 03060101, on left bank 40 ft downstream from State highway bridge, 0.8 mi downstream from Rices Creek, and 3.4 mi west of Liberty. DRAINAGE.--106 m12. PERIOD OF RECORD.--July 1954 to September 1964. GAGE.--Water-stage recorder. Datum of gage is 822.18 ft National Geodetic Vertical Datum of 1929 (levels by Soil Conservation Service). REMARKS.--Records good except those for periods of no gage-height record, which are fair. Storm runoff at gage affected by several small flood-detention reservoirs on tributary streams. EXTREMES FOR PERIOD OF RECORD.--Maxilm discharge, 5,360 ft3/s, Dec. 12, 1961, gage height, 12.23 ft. STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 4,020 ft3/s and graphically extended on logarithmic plotting paper. FLOOD-FREQUENCY DATA (ft3/5) LOG-PEARSON TYPE III STATISTICS (LOG UNITS) 10 YEARS OF RECORD Mean - 3.507 LOG-PEARSON TYPE III Standard Deviation . 0.125 Q = 3 180 Weighted Skew = 0.272 Q = 4:080 Q10 w 4,680 25 = 5 460 Q50 . 6:050 Q100 = 6,640 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height 3 year height 3 year height ft) (ft /5) (ft) (ft /5) (ft) (ft 3/a) 1955 Feb. 7 9.60 2,880 1959 June 1 9.30 2,710 1963 Mar. 6 11.38 4,680 1956 Apr. 16 9.37 2,760 1960 Mar. 31 8.71 2,490 1964 Jan. 25 9.59 3,300 1957 Apr. 5 9.80 2,930 1961 June 22 10.81 4,040 1958 July 9 6.56 1,380 1962 Dec. 12 12.23 5,360 117 SAVANNAH RIVER BASIN 02187000 SENECA RIVER NEAR ANDERSON, S.C. LOCATION.--Lat 34*29'10", long 82'49'45", Anderson County, Hydrologic-Unit 03060101, long 82*49'45", on right bank, 0.25 mi downstream from bridge on S:tate Highway 80, 1.9 mi downstream from Deep Creek, 4.2 mi upstream from confluence with Tugaloo River, and 10 mi west of Anderson. DRAINAGE AREA.--1026 m12. PERIOD OF RECORD.--June 1928 to January 1960. Monthly discharge only for some periods published in WSP 1303. GAGE.--Water-stage recorder. Elevation of gage is 520 ft (from Corps of Engineers profile). May 28, 1928, to January 23, 1929, staff gage and January 24, 1929, to October 12, 1933, water-stage recorder, at site 15 ft downstream at same datum. REMARKS.--Records good. Some regulation at low flow by powerplants above station. EXTREMES FOR PERIOD OF RECORD. --Maximum discharge, 81,100 ft3/s, Aug. 17, 1928, gage height, 25.75 ft. EXTREMES OUTSIDE PERIOD OF RECORD.--At least 90,200 ft3ls, Feb. 15, 1960, gage height 25.72 ft, from current- meter measurement. STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 18,000 fts/s and graphically extended an logarithmic plotting paper. FLOOD-FREQUENCY DATA (ft3/s) LOG-PEARSON TYPE III STATISTICS CLOG UNITS) 32 YEARS OF RECORD Mean . 4.368 LOG-PEARSON TYPE III Standard Deviation - 0.221 Q 2 = 23t100 Weighted Skew = 0.113 Q5 = 35,700 Q = 45,000 Q25 ' 58,000 950 = 68 400 Q100 = 79:50b Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height 3 year height 3 year height 3 (ft) (ft /s) (ft) (ft /a) (ft) (ft /a) 1928 Aug. 17 25.75 81,100 1939 Aug. 19 15.68 33 300 1950 Oct. 8 13.51 24,300 1929 Mar. 5 14.72 25,900 1940 Aug, 14 18.30 45:600 1951 Oct. 21 10.31 13,900 1930 Oct. 2 13.90 23,100 1941 July 7 10.13 13,300 1952 Mar. 12 15.37 32,000 1931 Nov. 17 8.20 7,800 1942 Feb@ 17 15.25 31,100 1953 Feb. 22 13.21 23,200 1932 Dec. 15 12.14 17,500 1943 Dec, 30 12.54 20,800 1954 Jan. 23 13.26 23,600 1933 Oct. 18 17.73 37,600 1944 Mar, 20 13.05 22,600 1955 Feb. 7 11.74 18,400 1934 Mar. 5 12.16 19,800 1945 Mar. 27 8.30 8,850 1956 Apr. 17 11.69 18,000 1935 Jan. 20 12.24 19,800 1946 Jan, 7 17.26 40,600 1957 Apr. 6 12.89 22,200 1936 Apr. 7 19.04 49,200 1947 Jan. 21 11.76 18,400 1958 Nov. 20 9.88 12,800 1937 Oct. 1 20.07 55,200 1948 Aug. 5 10.84 15,300 1959 Apr. 13 11.00 15,300 1938 Oct. 20 14.42 27,900 1949 Nov. 29 15.11 30,700 118 SAVANNAH RIVER BASIN 02187500 SAVANNAH RIVER NEAR IVA, SC LOCATION.--Lat 34*15'20", Anderson County, Hydrologic Unit 03060103, on left bank at downstream side of bridge on State Highway 184, 0.5 mi upstream from Little Generostee Creek, 5.8 mi southwest of Iva, and at mile 296.5. DRAINAGE AREA.--2,231 mi 2. PERIOD OF RECORD.--October 1949 to September 1981. Monthly discharge only for some periods, published in WSP 1303. GAGE.--Water-stage recorder. Datum of gage is 432.26 ft National Geodetic Vertical Datum of 1929 (levels by Corps of Engineers). REMARKS.--Records good. Flow regulated by powerplants above station, by Burton and Mathis Reservoirs, and by Hartwell Lake. Currently in backwater from Richard B. Russell Dam. 3 EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 54,400 ft /s, Mar. 12,1952, gage height, 12.74 ft. 3 STAGE-DISCHARGE RELATION.--Defined by current meter measurements below 52,300 ft and graphically extended on logarithmic plotting paper. Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height 3 year height 3 year height 3 (ft) (ft IS) (ft) (ft /a) (ft) /a) 1950 Oct. 10 --- 27,500 1960 Apr. 6 6.16 12,300 1970 July 29 8.51 28,600 1951 Oct. 21 8.98 -27,200 1961 Mar. 7 5.79 10,400 1971 Mar. 3 8.96 31,300 1952 Mar. 12 12.74 54,400 1962 Dec. 18 7.89 21,200 1972 Jan.-7 8.43 31,000 1953 Feb. 22 10.44 36,800 1963 Apr. 30 7.86 21,400 1973 Dec. 15 8.57 32,000 1954 Jan. 16 11.28 44,200 1964 Apr. 8 11.25 44,300 1974 Aug. 9 8.01 28,100 1955 Feb. 7 10.04 34,000 1965 Oct. 5 8.87 29,500 1975 Mar. 13 8.82 33,700 1956 Apr. 16 9.65 31,200 1966 Mar. 4 9.79 35,000 1976 Mar. 31 8.23 29,600 1957 Apr. 6 10.08 34,800 1967 June 6 8.88 30,800 1977 Mar. 30 8.12 28,800 1958 Nov. 19 9.67 32,000 1968 Jan. 12 8.58 29,000 1978 Jan. 25 8.47 31,300 1959 Apr. 13 8.22 22,000 1969 May 2 8.44 28,100 1979 Apr. 13 8.73 33,300 1980 Mar. 28 8.36 30,500 1981 July 24 7.99 27,800 SAVANNAH RIVER BASIN 02187900 BROADWAY CREEK NEAR ANDERSON, S.C. LOCATION.--Lat 34'30'09", long 82'3510011, Anderson County, Hydrologic Unit 03060103, at bridge on State Highway 48, 0.1 mi downstream from Cupboard Creek, and 3.8 mi east of Anderson. DRAINAGE AREA.--26.4 m12. PERIOD OF RECORD.--October 1974 to current year. GAGE.--Partial record crest gage, Elevation of gage is 660 ft (from topographic maps). REMARKS.--Records good. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 1,700 ft3/s, March 30, 1977, gage height, 11.80 ft. STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 1,600 fts/s and graphically extended on logarithmic plotting paper. FLOOD-FREQUENCY DATA.(ftS IS) LOG-PEARSON TYPE III STATISTICS (LOG UNITS) 10 YEARS OF RECORD Mean - 2,970 LOG-PEARSON TYPE III Standard Deviation - 0.244 Q2 - 954 Weighted Skew - -0.226 Q5 = 11500 Q10 = 11890 Q25 = 21390 Q = 2 770 50 = 3:150 Q100 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height year height year height 3 (ft) (ft3/s) (ft) (ft3/a) (ft) (ft ts) 1977 Mar. 30 11.80 1,700 1982 Jan. 4 10.30 1,400 1987 Mar. 1 9.42 1,220 1978 Jan. 25 10.18 1,380 1984 Feb. 14 9.82 1,300 1988 Apr. 12 4.36 361 1979 Apr. 13 11.16 1,570 1985 Feb. 6 5.80 560 1981 Feb. 10 5.53 520 1986 Nov. 1 5.98 587 120 SAVANNAH RIVER BASIN 02188000 ROCKY RIVER NEAR CALHOUN FALLS. S.C. LOCATION.--Lat 34*08', long 82*381, Abbeville County, Hydrologic Unit 03060103, on right bank, 2,000 ft upstream from Swanigan Mill bridge on county road, 3.2 mi northwest of Calhoun Falls, and 3.8 mi upstream from mouth. DRAINAGE AREA.--267 m12. PERIOD OF RECORD.--February 1950 to September 1966, crest-stage 1971-82. GAGE.--Digital water-stage recorder. Datum of &age is 403.04 ft National Geodetic Vertical Datum of 1929 (levels by Corps of Engineers). Prior to Aug. 13, 1964, graphic water-stage recorder at same site and datum. REMARKS.--Records good. Flow regulated by Lake Secession (usable capacity, about 17,420,000,000 cubic feet). City of Abbeville diverts a small amount of water during year for municipal supply. EXTREMES FOR PERIOD OF RECORD. --Maximum discharge, 10,900 ft3/s, Mar. 26, 1964, gage height, 12.79 ft. STAGE-DISCHARGE RELATION. --Defined by current-motor measurements below 8,450 ft3/s and graphically 'extended on logarithmic plotting paper. FLOOD-FREQUENCY DATA (ft3 Is) LOG-PEARSON TYPE III STATISTICS (LOG UNITS) -27 YEARS OF RECORD Mean - 3.649 LOG-PEARSON TYPE III Standard Deviation - 0.265 Q . 4,570 Weighted Skew - -0.241 Q5 - 7,500 - 9,580 Q 10 12 300 25 1 Q50 14,400 0100 16,500 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height year height 3 year height ft) (ft3 /s) (ft) (ft /a) (ft) (ft3 /s) 1951 Dec. 7 3.44 1,240 1961 Feb. 25 6.81 4,366 1975 Mar. 13 11.57 9,380 1952 Mar. 25 9.44 9,450 1962 Feb. 22 5.42 2,960 1976 Mar. 17 6.08 3,380 1953 Mar. 23 4.54 2,240 1963 Mar. 13 7.68 5,330 1977 Oct. 9 7.50 4,800 1954 Jan. 23 5.09 2,880 1964 Mar. 26 12.79 10,900 1978 Oct. 26 6.84 4,140 1955 Feb. 6 4.92 2,700 1965 Oct. 6 12.51 10,600 1979 Apr. 13 11.40 9,180 1956 Sept.27 6.22 4,110 1966 Mar. 5 9.57 7,030 1980 1957 Apr. 5 3.60 1,260 1971 Mar. 3 10.65 6,280 1981 Oct. 1 9.24 6,660 1958 Nov. 20 7.45 5,000 1972 Jan. 11 7.21 4,510 1982 Jan. 4 9.56 2,020 1959 Sept. 7 6.23 3,860 1973 Apr. 1 5.86 3,160 1960 Feb. 14 5.87 3,560 1974 Jan. 9 11.20 8,940 121 SAVANNAH RIVER BASIN 02189000 SAVANNAH RIVER NEAR CALHOUN FALLS, SC LOCATION.--Lat 34*04115", Abbeville County, Hydrologic Unit 03060103, on left bank 150 ft upstream from bridge on State Highway 72, 1.0 mi downstream from Seaboard Coast Line Railroad bridge, 1.5 mi downstream from Rocky River, 3.0 mi southwest of Calhoun Falls, and at mile 279.7. DRAINAGE AREA.--2,876 mi 2. PERIOD OF RECORD.--August 1896 to August 1898, March 1899 to December 1900, January to December 1903, March 1930 to July 1932, April 1938 to 1979. Published as "at Calhoun Falls" 1897-99. Records for January 1901 to December 1902, published in WSP 65, 75, and 83 have been found unreliable, and should not be used. Gage- height records collected at original site 1.0 mi upstream during 1899-1928 and at present site since 1928 are contained in reports of National Weather Service. GAGE.--Water-stage recorder. Datum of gage is 363.53 ft National Geodetic Vertical Datum of 1929. Prior to July 1, 1928, nonrecording gage at railroad bridge 1.0 mi kupstream at altitude 369.0 ft. REMARKS.--Records good. Flow regulated by powerplants above station, by Burton and Mathis Reservoirs, and by Hartwell Lake. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge 96,500 fts/s, Aug. 13, 1940, gage height, 11.52 ft. EXTREMES OUTSIDE PERIOD OF RECORD.--The flood of Aug. 25, 1908 reacbedo; ;t5ge og 28.2 ft at original site and datum, fr%m records of National Weatber Service, discharge, 144,0 t /s, from rating curve extended above 14, 000 ft / a. STAGE-DJS@HARGE RELATIONS. --Defined by current meter measurements below 50,000 ft3/s. Extended above 50,000 ft /a by velocity-area studies. Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height 3 year height year height (ft) (ft /3) (ft) (ft3/5) (ft) (ft3 /5) 1897 Apr. 5 --- 57,400 1927 Dec. 29 --- 27,800 1955 Feb. 7 6.89 40,200 1900 Feb. 14 --- 76,500 1928 Aug. 17 --- 130,000 1956 Sept.26 7.02 40,200 1901 Sept.18 --- 66,500 1929 Sept.27 --- 85,400 1957 Apr. 6 6.79 38,100 1902 Feb. 28 --- 76,100 1930 Oct. 2 --- 105,000 1958 Nov. 19 6.76 38,100 1903 June 7 --- 57,800 1931 Apr. 23 4.22 15,800 1959 June 2 6.41 32,800 1904 Aug. 9 --- 33,900 1932 Dec. 4 7.10 41,400 1960 Feb. 13 5.03 19,600 1905 July 2 --- 47,400 1933 Oct. 17 11.60 97,600 1961 Mar. 8 4.79 17,400 1906 Mar. 20 --- 42,200 1934 June 5 7.00 39,400 1962 Dec. 19 5.62 26,000 1907 Oct. 4 --- 33,900 1935 Jan. 10 6.00 29,400 1963 Apr. 30 6.12 30,900 1908 Aug. 25 --- 114,000 1936 Apr. 7 11.50 96,200 1964 Apr. 8 8.08 60,000 1909 June 4 --- 43,900 1937 Oct. 1 9.00 63,000 1965 Oct. 6 6.91 44,800 1910 Mar. 1 --- 45,200 1938 Oct. 20 8.20 53,100 1966 Mar. 4 7.50 52,500 1911 Jan. 4 --- 23,500 1939 Aug. 19 7.88 49,600 1967 June 5 6.76 39,900 1912 Mar. 16 --- 75,700 1940 Aug. 13 11.52 96,500 1968 Jan. 10 6.17 33,200 1913 Mar. 15 --- 48,300 1941 July 7 6.70 35,300 1969 Jan. 20 7.04 43,400 1914 Doc. 30 --- 22,200 1942 Feb. 18 7.73 47,200 1970 July 29 5.89 32,000 1915 July 1 --- 38,300 1943 Jan. 18 8.21 53,100 1971 Mar. 4 6.97 45,600 1916 Dec. 30 --- 44,800 1944 Mar. 20 7.91 49,500 1972 Jan. 10 6.20 35,700 1917 Mar. 25 --- 40,000 1945 Apr. 25 6.40 33,300 1973 Dec. 16 6.80 43,400 1918 Aug. 3 --- 26,100 1946 Jan. 8 9.41 68,400 1974 Apr. 5 5.84 31,400 1919 Dec. 23 --- 59,100 1947 Jan. 20 7.47 44,800 1975 Mar. 14 7.32 47,100 1920 Dec. 10 --- 63,100 1948 Mar. 7 6.11 29,800 1976 Mar. 16 6.72 39,400 1921 Feb. 9 --- 51,800 1949 Nov. 29 8.94 61,800 1977 Mar. 30 6.35 35,200 1922 Mar. 11 --- 34,800 1950 Oct. 8 5.98 29,400 1978 Jan. 26 7.16 45,000 1923 Dec. 19 --- 35,700 1951 Oct. 21 5.98 28,800 1979 Apr. 13 7.78 52,900 1924 Sept.21 --- 40,000 1952 Mar. 24 8.65 58,000 1980 Mar. 28 10.30 91,400 1925 Jan. 19 --- 31,700 1953 Feb. 22 6.94 38,400 1926 Jan. 19 --- 28,300 1954 Jan. 17 7.44 44,500 122 SAVANNAH RIVER BASIN 02192500 LITTLE RIVER NEAR MOUNT CARMEL, S.C. LOCATION.--Lat 34*04'13", long 82*30'02", McCormick County, on right bank 480 ft downstream from Island Ford bridge, 2.8 mi upstream from Calhoun Creek, and 4.5 mi north of Mount Carmel. DRAINAGE AREA.--217 m12. PERIOD OF RECORD.--December 1939 to 1970, crest-stage gage 1971 to current year. GAGE.--Water-stage recorder. Datum of gage is 353.97 ft National Geodetic Vertical Datum of 1929. REMARKS.--Records good except for periods of no gage-height record, which are poor. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 20,800 ft3 /a, #ug. 14, 1940, gag; @eight, 29.60 ft, (from high-water mark), from rating curve extended above 23,000 ft Is; minimum, 0.7 t /a, Oct. 9, 1954. STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 13,600 ft3/s and graphically extended on logarithmic plotting paper. FLOOD-FREQUENCY DATA (ft3 /s) LOG-PEARSON TYPE III STATISTICS (LOG UNITS) 46 YEARS OF RECORD Mean - 3.674 LOG-PEARSON TYPE III Standard Deviation - 0.237 Q - 4,730 Weighted Skew - -0.017 Q = 7,470 = 9,490 Q 10 = 12,200 Q 25 = 14,400 50 = 16,700 Q100 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height year height 3 year height 3 (ft) (ft3/.) (ft) (ft /a) (ft) (ft /a) 1940 Aug, 14 29.60 20,800 1960 Jan. 31 15.60 4,300 1980 1941 July 17 22.23 9,020 1961 Mar. 9 14.92 3,970 1981 Oct. 1 12.50 2,700 1942 Mar. 22 19.18 6,400 1962 Feb. 23 15.86 4,580 1982 Jan. 4 15.68 4,740 1943 Jan. 19 20.37 7,310 1963 Apr. 30 15.84 4,410 1983 1944 Mar. 20 20.90 8,020 1964 Mar. 27 23.11 10,000 1984 Jan. 11 15.50 4,240 1945 Apr. 25 16.88 5,020 1965 Mar. 25 19.76 6,800 1985 Feb. 6 12.51 2,710 1946 Dec. 25 13.00 3,210 1966 Mar. 5 18.96 6,230 1986 1947 Jan. 20 17.35 5,300 1967 Aug. 25 11.79 2,390 1987 Mar. 1 16.89 5,010 1948 Nov. 11 12.81 3,130 1968 Jan. 11 16.70 4,900 1988 Jan. 20 4.48 390 1949 Nov. 29 22.55 9,350 1969 Jan. 21 19.61 6,690 1950 July 25 8.74 1,760 1970 Mar. 22 10.63 1,950 1951 Apr. 2 7.55 1,440 1971 Mar. 3 22.64 9,500 1952 Mar. 4 19.47 6,610 1972 Jan. 11 18.99 6,260 1953 May 1 12.68 2,970 1973 Apr. 1 23.60 10,600 1954 Jan. 17 13.93 3,490 1974 Jan. 10 14.62 3,760 1955 Feb. 7 15.64 4,310 1975 Mar. 13 22.86 9,750 1956 Mar. 17 14.34 3,450 1976 Mar. 17 17.58 5,390 1957 Apr. 5 9.23 1,900 1977 Oct. 9 23.02 2,960 1958 Nov. 19 18.20 5,760 1978 Oct. 26 16.51 4,800 1959 Sept. 7 17.57 5,400 1979 Apr. 13 18.25 5,790 123 SAVANNAH RIVER BASIN 02195000 SAVANNAH RIVER NEAR CLARKS HILL, SC LOCATION.--Lat 33*38140", long 82*12'05", McCormick County, Hydrologic Unit 03060107, on right bank 1.2 miles downstream of Thurmond Dam, 2.4 miles southwest of Clarks Hill, 2.5 miles upstream from Kiokee Creek, and at mile 221.1 upstream from Savannah, Ga. DRAINAGE AREA.--6,150 mi 2 (approximately). PERIOD OF RECORD.--May 1940 to June 1954. GAGE.--Water stage recorder. Datum of gage is 182.69 ft, National Geodetic Vertical Datum of 1929 (levels by Corps of Engineers). Auxiliary water-stage recorder 6.3 miles downstream. REMARKS.--Records fair. Prior to December 1951 some regulation by Burton and Mathis Reservoirs and powerplants above station. From 1951 flow completely regulated by Thurmond Reservoir. 3 EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 196,000 ft /a, Aug. 14, 1940, gage height, 29.34 ft. STAGE-DISCHARGE RELATION.--Defined by discharge measurements throughout entire range of flows. Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height 3 year height 3 year height 3 (ft) (ft /3) (ft) (ft /a) (ft) (ft /8) 11940 Aug. 14 29.34 196,000 1945 Apr. 26 15.72 61,200 1950 Oct. 9 11.61 36,800 1941 July 8 14.12 54,900 1946 Jan. 8 22.11 110 000 21951 Oct. 22 14.54 48,700 1942 Mar. 23 20.77 99,300 1947 Jan. 21 19.99 87:000 1952 Mar. 7 11.56 35,400 1943 Jan. 20 22.16 111,000 1948 Feb. 10 16.61 63,600 31953 May 7 10.52 30,000 1944 Mar. 21 22.31 111,000 1949 Nov. 30 26.35 154,000 1954 Mar. 30 10.67 30.000 1 Period May to September 2 March 25, 1952 3 Period October to June 124 SAVANNAH RIVER BASIN 02196000 STEVENS CREEK NEAR MODOC, S.C. LOCATION.--Lat 33*4314511, long 82*10155". Edgefield County, Hydrologic Unit 03060107, on left bank at bridge on State Highway 23, 1.4 mi east of Modoc, and 3.2 mi downstream from Turkey Creek. DRAINAGE AREA.--545 m12, approximately. PERIOD OF RECORD.--November 1929 to September 1931, February 1940 to September 1978, November 1983 to current year. Monthly discharge only for some periods, published in WSP 1303. GAGE.--Water-stage recorder. Datum of gage is 197.34 ft National Geodetic Vertical Datum of 1929 (levels by Southeastern Power Administration). October 15, 1929, to Sept. 30, 1931, nonrecozding gage at site 1,100 ft upstream at different datum. REMARY,S.--Records good. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 35,100 ft3/s, Aug. 14, 1940, gage height, 41.08 ft. STAGE-DISCHARGE RELATION. --Defined by cuzrent-meter measurements below 26,200 ft3/s and graphically extended on logarithmic platting paper. FLOOD-FREQUENCY DATA (ftsts) LOG-PEARSON TYPE III STATISTICS (LOG UNITS) 4 EARS OF RECORD Mean = 4.091 Lk! PEARSON TYPE III Standard Deviation = 0.217 = 12,600 Weighted Skew = -0.234 QQ2 - 18,900 Q 5 - 23,100 Q10 - 28 400 25 1 Q50 ' 32,300 Q100 = 36,200 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year h7ight (ft3ls) year height 3 year height 3 ft) (ft) (ft /a) (ft) (ft /a) 1931 Apr. 1 5,550 1954 Jan. 16 14.47 4,110 1969 Apr. 16 34.25 22,700 1940 Aug. 14 41.08 35,100 1955 Apr. 15 24.75 11,300 1970 Mar. 22 24.66 10,800 1941 June 25 6,000 1956 Apr. 12 22.74 9,430 1971 Mar. 3 32.47 20,100 1942 Mar. 22 29.64 16,800 1957 May 5 20.32 7,330 1972 Jan. 12 27.07 13,200 1943 Jan. 19 18,700 1958 Apr. 16 28.87 15,900 1973 Apr. 1 27.92 14,100 1944 Mar. 21 35.88 26,200 1959 Mar. 6 20.60 7,600 1974 Apr. 5 27.28 13,400 1945 Apr. 25 20.10 7,220 1960 Jan. 31, 29.07 16plOO 1975 Mar. 3 30.16 16,900 1946 Dec. 26 25.27 11,800 1961 Feb. 25 31.26 19,000 1976 Mar. 17 25.97 12olOO 1947 Mar. 8 24.41 11.000 1962 Jan. 7 32.57 20,900 1977 Oct. 9 30.87 17,800 1948 Feb. 10 27.36 14,200 1963 Mar. 13 23.44 10,100 1978 May 9 25.94 12,000 1949 Nov. 29 30.27 17,700 1964 Aug. 31 38.89 30,900 1984 Jan. 11 24.18 20,300 1950 Mar. 7 14.50 4,060 1965 Dec. 27 32.90 20.700 1985 Feb. 6 26.31 12,400 1951 Apr. 3 19.66 6,760 1966 Mar. 5 27.13 13,200 1986 Oct. 4 21.41 7,950 1952 Mar. 5 30.59 18,200 1967 May 23 20.28 7,020 1987 Jan. 23 24.25 10,400 1953 Feb. 15 21.51 8,360 1968 Jan. 11 28.15 14,400 1988 Sept. 9 15.93 4,760 125 SAVANNAH RIVER BASIN 02197000 SAVANNAH RIVER AT AUGUSTA, GA LOCATION.--Lat 33'22125", long 81'5613511, Richmond County, Hydrologic Unit 03060106, at New Savannah Bluff lack and dam, 0.2 mi upstream from Butler Creek, 12.0 mi downstream from Augusta, and at mile 187.4. DRAINAGE AREA.--7,508 m12, including that of Butler Creek. PERIOD OF RECORD.--October 1883 to December 1891, January 1896 to December 1906, January 1925 to current year. Monthly discharges only for some periods, published in WSP 1303. Gage-height records collected at site of Fifth street gage from 1875 to 1952 and at New Savannah Bluff lock and dam sites since 1937 are contained in reports of National Weather Service. GAGE.--Water-stage recorder. Datum of gage is 96.58 ft, National Geodetic Vertical Datum of 1929 (Corps of Engineers bench mark). Oct. 1, 1883 to Dec. 31, 1891, Jan. 1, 1896, to Dec. 31, 1906, Jan. 1, 1925, to Sept. 30, 1932, nonrecording gage at Fifth Street Bridge at datum 102.06 ft NGVD (levels by Southeastern Engineering Co.). Oct. 1, 1932 to Sept. 30, 1936, recording gage at Thirteenth Street bridge at datum 104.56 ft NGVD (levels by Corps of Engineers). Oct. 1, 1936, to Nov. 10, 1948, recording gage at site 0.2 mi downstream from present site and at present datum. REMARKS.--Records good, Flow regulated by Hartwell Lake, by Thurmond Lake, by Richard B. Russell Lake, and by other powerplants above station. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 350,000 fts/s, Oct. 3, 1929- maximum gage height, 46.3 ft, Sept. 27, 1929 (at site and d5tum then in use); minimum digcharge, 648 fts/s, Sept. 24, 1939, from rating curve extended below 1,400 ft /a; minimum daily, 1,040 ft Is, Oct. 2, 1927. EXTREMES OUTSIDE PERIOD OF RECORD.--Flood of January 17, 1796, reached a stage of about 40 feet (at site and datum of Fifth Street gage), marked by local residents; discharge approximately 360,000 ft3/s, by slope conveyance study. Little information exists and the data are considered approximate. Data furnished by the U.S. Army Corps of Engineers. STAGE-DISCHARGE RELATION.--Peak discharges prior to 1912, excluding the 1796 flood, were determined using a stage-discharge rating established by discharge measurements made during the 1890's and early 1900's. The stage-discharge relation is defined by direct measurement. FLOOD-FREQUENCY DATA.--Th,e flood-frequency relation for this station was computed by routing pre-regulation hydrograpbs through the existing system of reservoirs using the methodology described by Sanders and others (1990). Interested individuals should consult this reference for further frequency information at this site. 126 SAVANNAH RIVER BASIN 02197000 SAVANNAH RIVER AT AUGUSTA, GA, Continued Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height year height year height (ft) (ft3/s) (ft) (ft3/s) (ft) (ft3 /S) I 1796 Jan. 17 40.00 360,000, 1911 Apr. 14 19.10 32,800 31951 Oct. 22 22.32 46,300 1840 May 28 37.80 270,000* 1912 Mar. 17 36.80 234,000 1952 Mar. 6 21.53 39,300 21852 Aug. 29 37.40 250,000, 1913 Mar. 16 35.10 156,000 1953 May 8 20.80 35,200 1864 Jan. 1 34.9 185,000* 1914 Dec. 31 24.30 48,000 1954' Mar. 30 17.39 25,500 1865 Jan. 11 36.90 240,000 1915 Jan. 20 28.20 61,000 1955 Apr. 15 16.77 23,900 1876 Dec. 30 28.60 86,400 1916 Feb. 3 31.00 82,400 1956 Apr. 12 14.70 18,600 1877 Apr. 14 31.40 119,000 1917 Mar. 6 29.20 68,000 1957 May 7 14.08 18,000 1878 Nov. 23 23.50 51,500 1918 Jan. 30 25.50 45,500 1958 Apr. 18 22.91 66,300 1879 Aug. 3 22.00 44,000 1919 Dec. 24 35.00 128,000 1959 June 8 18.65 28,500 1880 Dec. 16 30.10 102,000 1920 Dec. 11 35.40 133,000 1960 Feb. 14 20.58 34,900 1881 Mar. 18 32.20 130,000 1921 Feb. 11 35.10 129,000 41951 Apr. 2 20.56 34,800 1882 Sept.12 29.30 93,300 1922 Feb. 16 32.00 92,000 1962 Jan. 9 20.09 32,500 1883 Jan. 22 30.80 111,000 1923 Feb. 28 28.00 59,700 1963 Mar. 23 19.52 31,300 1884 Apr. 16 28.00 81,000 1924 Sept.22 28.00 59,700 1964 Apr. 9 24.16 87,100 1885 Jan. 26 27.50 77,000 1925 Jan. 20 36.50 150,000 1965 Dec. 27 20.62 34,600 1886 May 21 32.50 135,000 1926 Jan. 20 27.30 55,300 1966 Mar. 6 21.50 39,300 1887 July 31 34.50 173,000 1927 Dec. 30 24.00 39,000 1967 Aug. 25 18.10 26,500 1888 Sept.11 38.70 303,000 1928 Aug. 17 40.40 226,000 1968 Jan. 12 20.94 35,900 1889 Feb. 19 33.30 149,000 1929 Sept.27 46.30 343,000 1969 Apr. 21 22.24 45,600 1890 Feb. 27 22.90 48,500 1930 Oct. 2 45.10 350,000 1970 Apr. 1 17.68 25,200 1891 Mar. 10 35.50 197,000 1931 Nov. 17 19.90 26,100 1971 Mar. 5 23.30 63,900 1892 Jan. 20 32.80 140,000 1932 -Jan. 9 30.40 93,800 1972 Jan. 20 20.36 33,700 1893 Feb. 14 25.00 60,000 1933 Oct. 18 30.30 92,600 1973 Apr. 8 21.63 40,200 1894 Aug. 7 24.00 54,000 1934 Mar. 5 28.50 73,200 1974 Feb. 23 20.13 32,900 1895 Jan. 11 30.40 106,000 1935 Mar. 14 27.40 63,700 1975 Mar. 25 22.24 45,600 1896 July 10 30.50 107,000 1936 Apr. 8 41.20 258,000 1976 June 5 20.27 33,300 1897 Apr. 6 29.30 93,300 1937 Jan. 4 30,10 91,400 1977 Apr. 7 20.50 34,200 1898 Sept. 2 31.30 117,000 1938 Oct. 21 30.10 91,400 1978 Jan. 26 21.98 43,100 1899 Feb. 8 31.00 113,000 1939 Mar. 2 24.10 90,900 1979 Feb. 27 21.13 37,300 1900 Feb. 15 32.70 138,000 1940 Aug. 15 29.40 239,000 1980 Mar. 31 22.33 47,200 1901 Apr. 4 31.80 124,000 1941 July 8 22.89 53,300 1981 Feb. 12 14.70 17,700 1902 Mar. 1 34.60 175,000 1942 Mar 23 24.56 105,000 51982 Jan. 2 19.39 30,700 1903 Feb. 9 33.20 147,000 1943 Jan 20 25.10 117,000 1983 Apr. 10 23.21 66,100 1904 Aug. 10 25.50 63,000 1944 Mar 22 25.53 128,000 1984 May 5 20.35 34,000 1905 Feb. 14 25.80 64,800 1945 Apr 27 23.16 64,000 1985 Feb. 7 17.89 25,700 1906 Jan. 5 29.60 96,600 1946 Jan 9 24.43 97,200 1986 Oct. 3 15.74 21,000 1907 Oct. 5 23.60 52,000 1947 Jan 22 23.97 86,000 1987 Mar. 6 18.98 29,200 1908 Aug. 27 38.80 307,000 1948 Feb 10 23.90 83,200 1988 Feb. 5 10.61 13,600 1909 June 5 28.70 87,300 1949 Nov 30 26.61 154,000 1910 Mar. 2 26.40 69,800 1950 Oct 9 20.10 32,500 1 Flood of January 17, 1796, reached a stage of about 40 fe5t (at site and datum of Fifth Street gage), marked by local residents; discharge approximately 360,000 ft /s, by slope conveyance study. Little iInformation exists and the data are considered approximate. Data furnished by the U.S. Army Corps of Engineers. 2 U.S. House of Representatives Document No. 64. 3 Filling of Thurmond Lake begain In December 1951. 4 Filling of Hartwell Lake began in February 1961. 5 Filling of Russell Lake began in October 1984. Estimated values. 127 SAVANNAH RIVER BASIN 02197300 UPPER THREE RUNS NEAR NEW ELLENTON, SC LOCATION.--Lat 33*23'05", long 81'37'00", Aiken County, Hydrologic Unit 03060106, on downstream side of bridge on U.S. Highway 278, 0.4 mi upstream from Johnson Fork Creek, and 4.6 mi southeast of New Ellenton. DRAINAGE AREA.--87.0 m12. PERIOD OF RECORD.--June 1966 to current year. GAGE.--Water-stage recorder. Elevation of &age is 175 ft, National Geodetic Vertical Datum of 1929. REMARKS.--Records good. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 472 fts/s, June 13, 1973, gage height, 8.37 ft. STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 388 ft3/s and graphically extended on logarithmic plotting paper. FLOOD-FREQUENCY DATA (ft3ls_) LOG-PEARSON TYPE III STATISTICS (LOG UNITS) 22 YEARS OF RECORD Mean - 2.539 LOG-PEARSON TYPE III Standard Deviation - 0.078 Q2 = 347 Weighted Skew - -0.120 Q 5 = 402 Q10 = 434 Q - 469 Q 25 = 493 50 = 516 Q100 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height year height year height 3 3 3 (ft) (ft /s) (ft) (ft /s) ft) (ft /s) 1967 Aug. 24 320 1977 Mar. 22 7.07 304 1987 Mar. 1 7.60 370 1968 June 9 6.07 237 1978 Jan. 25 7.38 344 1988 Sept. 9 6.86 278 1969 Sept.19 6.91 301 1979 Apr. 26 7.36 341 1970 Mar. 30 6.83 303 1980 Mar. 13 7.77 400 1971 Aug. 17 8.00 420 1981 Feb. 11 7.10 308 1972 Aug. 17 7.52 372 1982 Jan. 1 7.57 364 1973 June 13 8.37 472 1983 Mar. 6 7.32 331 1974 Feb. 7 6.60 260 1984 May 4 8.13 466 1975 July 15 7.34 341 1985 Feb. 6 7.75 400 1976 May 29 7.96 429 1986 Nov. 22 7.50 360 128 SAVANNAH RIVER BASIN 02197310 UPPER THREE RUNS ABOVE ROAD C AT SAVANNAH RIVER PLANT, SC LOCATION.--Lat 33*17'08", long 81*41'40", Aiken County, Hydrologic Unit 03060106, on right bank, 100 ft upstream of SRP Road C, 2.0 mi east of SRP Road 2, at Savannah River Plant, 6 mi southeast of New Ellenton. DRAINAGE AREA.--176 m12. PERIOD OF RECORD.--June 1974 to current year. GAGE.--Data collection Platform. Elevation of gage is 125 ft above National Geodetic Vertical Datum of 1929 (from topographic map). REMARKS.--Records good. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 962 ft3/s, Feb. 6, 1985, gage height, 6.25 ft. STAGE-DISCHARGE RELATION. --Defined by current-meter measurements below 736 ft3/s and graphically extended on logarithmic plotting paper. FLOOD-FREQUENCY DATA (ft3 /s) LOG-PEARSON TYPE III STATI!@TICS (LOG UNIT�j 14 YEARS OF RECORD Mean 2. 838 LOG-PEARSON TYPE III Standard Deviation . 0.090 Q = 692 Weighted Skew - -0.108 Q 2 = 822 Q 5 = 897 Q 10 984 Q 25 1 040 50 1:100 Q100 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height 3 year height 3 year height 3 (ft) (ft /s) (ft) (ft /a) (ft) (ft /a) 1975 July 16 5.74 586 1980 Max. 13 6.10 880 1985 Feb. 6 6.25 962 1976 May 29 5.47 732 1981 June 8 5.42 582 1986 June 11 5.96 802 1977 Mar. 23 5.51 540 1982 Jan. 1 5.73 696 1987 Mar. 1 6.12 891 1978 Jan. 26 6.04 646 1983 Mar. 7 5.59 641 1988 Sept.10 4.96 460 1979 Feb. 25 6.21 680 1984 May 5 6.08 840 129 SAVANNAH RIVER BASIN 02197315 UPPER THREE RUNS AT ROAD A AT SAVANNAH RIVER PLANT, S.C. LOCATION.--Lat 33*14'20', long 81*44'42", Aiken County, Hydrologic Unit 03060106, near right bank, on downstream side of bridge at SRP Road A, 2.0 mi south of SRP Road 2, at Savannah River Plant. DRAINAGE AREA.--203 mi2. PERIOD OF RECORD.--June 1974 to January 1978, October 1978 to current year. GAGE.--Water-stage recorder. Elevation of gage is 90 ft above National Geodetic Vertical Datum of 1929 (from topographic map). REMARKS.--Records good. EXTREMES FOR PERIOD OF RECORD. --Maximum discharge, 1,230 ft3/s, May 29, 1976, gage height, 6.76 ft. 3 STAGE DISCHARGE RELATION--Defined by current-meter measurements below 809 ft /a and graphically extended on logarithmic plotting paper. FLOOD-FREQUENCY DATA CfOL-) LOG-PEARSON TYPE III STATISTICS (LOG UNITS) 13 YEARS OF RECORD Mean = 2.906 LOG-PEARSON TYPE III Standard Deviation = 0.091 Q2 = 804 Weighted Skew - 0.064 Q5 = 961 Q10 1,060 Q25 1,170 Q50 1,250 Q100 1,330 Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height 3 year height year height @ft) (ft /a) (ft) (ft3Is) (ft) (ft 3Is) 1975 July 16 5.74 626 1980 Mar. 14 6.23 951 1965 Feb. 7 6.09 893 1976 May 29 6.76 1,230 1981 Feb. 12 5.33 620 1986 Nov. 23 5.80 780 11977 Mar. 23 5.62 717 1982 Jan. 2 5.83 793 1987 Mar. 1 6.03 869 1978 ------ ---- ---- 1983 Apr. 11 6.36 1010 1988 Sept.11 4.49 428 1979 Feb. 25 6.33 730 1984 May 5 6.01 861 1No record for period of Jan 10, 1978 to Oct 25, 1978 because gage was removed for construction of new bridge. 130 SAVANNAH RIVER BASIN 02197500 SAVANNAH RIVER AT-BURTONS FERRY BRIDGE, NEAR MILLHAVEN, GA LOCATION.--Lat 32*56120", long 81*30'10", Screven County (GA) - Allendale County (SC, Goergia-South Carolina State line, Hydrologic Unit 03060106, on right bank 500 ft downstream from U.S. Highway 301 bridge, 2.0 mi downstream from Rocky Creek, 9.0 mi east of Millhaven, and at mile 118.7 (revised). DRAINAGE AREA.--8,650 m12, approximately. PERIOD OF RECORD.--October 1939 to September 1970, October 1982 to current year. GAGE.--Water-stage recorder and data collection platform. Datum of gage is 52.42 ft above National Geodetic Vertical Datum of 1929. REMARKS.--Records good. Flow regulated by Thurmond Lake and affected by regulation of Hartwell Lake and Richard B. Russell Lake. EXTREMES FOR PERIOD OF RECORD.--Maximum dischrge, 141,000 ft3/s, Aug 18, 1940, gage height, 27.0 ft. EXTREMES OUTSIDE PERIOD OF RECORD.--Flood in October 1929 reached a stage of 30.8 ft from information by Corps of Engineers, discharge, 220,,000 ft /s, from rating curve extended graphically above 141,000 ft /s on logarithmic plotting paper. STAGE-DISCHARGE RELATION. --Defined by current meter measurements up to 141,000 ft3/s, which is maximum for period of record. Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date . Gage Discharge year height 3 year height 3 year height (ft) (ft /s) (ft) (it /s) (ft) (ft3 /s) 1930 Oct. 30.80 220,000 1952 Mar. 29 18.26 38,500 1965 Apr. 4 17.66 32,800 1940 Aug. 18 27.00 141,000 1953 May 13 17.52 31,800 1966 Mar. 9 18.05 37,100 1941 July 13 18.20 38,400 1954 Apr. 6 14.40 17,600 1967 June 17 15.47 22,000 1942 Mar, 26 22.00 73,000 1955 Apr. 18 113.21 15,000 1968 Jan. 16 16.64 26,800 1943 Jan. 23 22.60 80,900 1956 Mar. 19 11.95 13,700 1969 Apr. 25 18.31 37,200 1944 Mar. 26 23.40 89,300 1957 May 11 12.27 13,900 1970 Apr. 4 14.14 18,200 1945 May 1 18.80 42,900 1958 Apr. 22 18.94 41,400 1983 Apt. 15 --- 60,000 1946 Jan. 12 21.60 68,600 1959 June 13 16.59 27,400 1984 May 12 17.83 33,900 1947 Jan. 25 21.53 67,500 1960 Feb. 17 18.28 37,100 1985 Feb. 10 14.69 19,700 1948 Feb. 14 21.10 61,000 1961 Apr. 25 17.60 32,400 1986 Nov. 25 12.71 15,200 1949 Dec. 3 24.91 108,000 1962 Jan. 15 16.75 27,400 1987 Mar. 10 16.79 27,600 1950 Oct. 14 14.87 18,500 1963 Mar. 27 17.22 2g'200 1988 Oct 2 10.80 11,900 1951 Oct. 27 16.53 25,700 1964 Apr. 15 22.10 71,700 2Peak gage height occurred April 14. 131 SAVANNAH RIVER BASIN 02198500 SAVANNAH RIVER NEAR CLYO, GA LOCATION.--Lat 32*3113011, long 81*15'45", Effingham County (GA) - Jasper County (SC), Hydrologic-Unit 03060109, at Georgia-South Carolina State line, on downstream side of center pier of drawspan of bridge on Seaboard Coast Line Railroad, 3.0 mi north of Clyo, and at mile 60.9. DRAINAGE AREA.--9,850 mi2, approximately. PERIOD OF RECORD.--October 1929 to September 1933, October 1937 to current year. Monthly discharge only for some periods, published in WSP 1303. Gage-height records collected at same site 1921-43 by National Weather Service (unpublished prior to 1933). GAGE.--Water-stage recorder. Datum of gage is 13.39 ft National Geodetic Vertical Datum of 1929. Prior to Jan. 31, 1933, nonrecording gage at same site and at datum 4.00 ft higher. Jan. 31, 1933, to June 12, 1945, nonrecording gage at same site and datum. REMARKS.--Records good. Flow regulated by Hartwell Lake, by Thurmond Lake, Richard B. Russell Lake and by other powerplants above station. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 270,000 ft3/s, Oct. 6, 1929, gage height, 29.7 ft, present datum (from information by Corps of Engineers). 3 STAGE-DISCHARGE RELATION.--Defined by current meter measurements below 119,000 ft /s and graphically extended on logarithmic plotting paper. Peak Stages and Discharges Water Date Gage Discharge Water Date Gage Discharge Water Date Gage Discharge year height year height year height (ft) (ft3 /s) (ft) (ft 3/s) (ft) (ft 3 /5) 1925 Jan. 24 23.90 134,000 1947 Jan. 28 19.40 63,200 1969 Apr. 29 16.74 39,700 1926 Jan. 28 15.40 31,400 1948 Feb, 17 19.66 71,000 1970 Apr. 7 13.31 21,000 1927 Mar. 6 13.40 30,600 1949 Dec. 6 22.17 104,000 1971 Mar. 6 18.11 54,500 1928 Aug. 23 22.30 106,000 1950 Oct. 19 12.21 16,000 1972 Jan. 26 16.30 36,400 1929 Mar. 11 23.60 128,000 1951 Nov. 1 13.38 22,600 1973 Apr. 15 17.29 44,500 1930 Oct. 6 29.70 270,000 1952 Apr. 2 16.90 41,300 1974 Mar. 1 15.78 33,000 1931 Nov. 28 12.77 18,200 1953 May 17 15.80 35,800 1975 Mar. 24,30 17.83 50,600 1932 Jan. 15 19.18 59,600 1954 Apr. 12 12.49 18,800 1976 June 14,15 15.87 33,500 1933 Jan. 4 19.20 59,600 1955 Apr. 23 11.35 15,500 1977 Dec. 22 15.85 33,400 1934 June 15. 17.20 43,800 1956 Mar. 22 10.47 14,100 1978 Feb. 3 16.81 38,700 1935 Mar. 22 15.20 29,100 1957 May 15 11.15 15,000 1979 Apr. 27 16.34 36,600 1936 Apr. 13 26.00 176,000 1958 Apr. 25 17.41 45,500 1980 Apr. 2 18.40 58,600 1937 Jan. 11 19.40 65,800 1959 June 18 14.36 26,000 1981 Feb. 16 10.39 13,600 1938 Apr. 16 17.80 48,400 1960 Feb. 19 17.35 40,900 1982 Jan. 11 12.89 19,500 1939 Mar. 8 20.40 70,100 1961 Apr. 25 16.20 34,900 1983 Apr. 17 18.40 58,600 1940 Aug. 22 23.60 128,000 1962 Jan. 19 114.98 28,200 1984 May 14 16.48 37,700 1941 July 17 16.30 36,500 1963 Mar. 31 15.27 29,200 1985 Feb. 15 12.89 19,500 1942 Mar. 29 20.00 73,000 1964 Apr. 18 20.22 83,800 1986 Nov. 28 11.50 15,800 1943 Jan. 27 20.00 73,000 1965 Apr. 6 16.52 38,000 1987 Mar. 13 15.57 29,700 1944 Mar. 29 21.60 95,200 1966 Mar. 11 17.10 42,800 1988 Oct. 4 8.93 11,400 1945 May 5 16.00 34,400 1967 June 22 13.67 22,500 1946 Jan. 16 19.50 64,400 1968 Jan. 21 14.84 28,000 lOccurred at different time than peak discharge. 132 Table l.--Weighted flood discharges for selected recurrence intervals for rural streamflow stations used in the regionalization study Map Station Period Drainage index name of area Flood discharge, in cubic feet per second, for number and record (square indicated recurrence interval, in years number (years) miles) 2 5 10 25 50 100 Lower Coastal Plain 1 Waccamaw 38 1,110 5,510 8,560 10,600 13,500 15,500 17,800 River at Longs, S.C. (02110500) 2 Catfish 22 27.4 291 505 675 913 1,110 1,330 Canal at Sellers, S.C. (02131150) 3 Carter 18 8.28 211 375 502 687 835 1,000 Creek near Effingham, S.C. (02131990) 4 Two Mile 13 19.0 266 489 675 958 1,200 1,480 Branch near Lake City, S.C. (02132100) Table l.--Weighted flood discharges for selected recurrence intervals for rural streamflow stations used in the regionalization study--Continued Map Station Period Drainage index name of area Flood discharge, in-cubic feet per second, for number and record (square indicated recurrence interval, in years number (years) miles) 2 5 10 25 50 100 Lower Coastal Plain 5 Black 31 401 2,720 4,580 5,820 7,590 8,810 10,200 River near Gable, S.C. (02135500) 6 Black 61 1,252 5,640 10,300 15,200 29,500 45,300 66,500 River near Kingstree, S.C. (02136000) 7 Wedboo 21 17.4 274 558 788 1,130 1,400 1,710 Creek near Jamestown, S.C. (02171680) 8 Cow Castle 10 23.4 427 822 1,150 1,690 2,140 2,680 Creek near Bowman, S.C. (02174250) Table I.--Weighted flood discharge for selected recurrence intervals for rural streamflow stations used in the regionalization study--Continued Map Station Period Drainage index name of area Flood discharge, in cubic feet per second, for number and record (square indicated recurrence interval, in years number (years) miles) 2 5 10 25 50 100 Lower Coastal Plain 9 Savannah 12 12.4 286 467 606 814 973 1,170 Creek near Ehrhardt, @S.C. (02175450) 10 Combahee 15 1,100 5,650 8,800 10,800 14,000 16,100 18,700 River near Yemassee, S.C. (02176000) 11 Coosawatchie 38 203 1,670 2,740 3,530 4,710 5,620 69660 River near Hampton, S.C. (02176500) 12 Buckhead 21 64.0 1,150 2,?60 3,210 4,660 6,060 7,710 Creek near Waynesboro, Ga. (02201350) Table 1.--Weighted flood discharges for selected recurrence intervals for rural streamflow stations used in the regionalization_@ @ud --Continued Map Station Period Drainage index name of area Flood discharge, in cubic feet per second, for number and record (square indicated recurrence interval, inyears number (years) miles) 2 5 10 25 50 100 Lower Coastal Plain 13 Richardson 21 43.0 664 1,210 1,640 2,260 2,810 3,410 Creek near Millen, Ga. (02201800) 14 Hooker 24 4.38 163 222 263 311 348 386 Branch Tributary near Millen, Ga. (02201830) 15 Mill Creek 12 39.0 724 1,070 1,300 1,600 1,820 2,040 near Statesboro, Ga. (02202300) 16 Canoochee 26 55.0 772 1,250 1,600 2,100 2,490 2,910 Creek near Swainboro, Ga. (02202800) Table l.--Weighted flood discharges for selected recurrence intervals for rural streamflow stations used in the regionalization_@ @ud --Continued Map Station Period Drainage index name of area Flood discharge, in cubic feet per second, for number and record (square indicated recurrence interval, in years number (years) miles) 2 5 10 25 50 100 Lower Coastal Plain 17 Reedy 10 8.99 272 420 539 707 843 990 Creek near Twin City, Ga. (02202820) 18 Reedy 10 3.41 186 265 321 394 447 499 Branch near Metter, Ga. (02202850) 19 Fifteen 21 147 1,600 2,550 3,240 4,150 4,900 5,680 Mile Creek near Metter, Ga. (02202900) 20 Ten Mile 24 1.14 97 181 252 359 453 561 Creek near Pulaski, Ga. (02202910) Table l.--Weighted flood discharges for selected recurrence intervals for rural streamflow stations used in the regionalization @@d --Continued Map Station Period Drainage index name of area Flood discharge, in cubic feet per second, for number and record (square indicated recurrence interval, in years number (years) miles) 2 5 10 25 50 100 Lower Coastal Plain 21 Canoochee 51 555 4,020 6,610 8,680 11,700 14,400 17,400 River near Claxton, Ga. (02203000) 01) 22 Lotts 10 2.37 143 272 371 507 622 743 Creek near Statesboro, Ga. (02203150) 23 'Peacock 11 33.0 478 838 1,120 1@490 1,780 2,100 Creek at McIntosh, Ga. (02203559) 24 Reese Creek 17 9.96 189 384 560 864 1,150 1@530 near Fayette- ville, N.C. (02104080) Table i.--Weighted flood discharges for selected recurrence intervals for rural streamflow stations used in the regionalization study -Continued Map Station Period Drainage index name of area Flood discharge, in cubic feet per second, for number and record (square indicated recurrence interval, in years number (years) miles) 2 5 10 25 50 100 Lower Coastal Plain 25 Browns 18 11.3 163 440 729 1,280 1,830 2,500 Creek near Elizabeth- town, N.C. (02105570) 26 Turnbull 19 60.1 529 1,140 1,730 2@750 3J20 4,890 Creek near Elizabeth- town, N.C. (02105630) 27 Hood Creek 21 19.7 598 1@060 1,440 2tOlO 2,500 3tO6O near Leland, N.C. (02105900) 28 Little 35 92.8 915 1@610 2,220 3,200 4,070 5tI20 Coharie Creek near Roseboro, N.C. (02106000) Table l.--Weighted flood discharges for selected recurrence intervals for rural streamflow stations used in the regionali@@tion study--Continued Map Station Period Drainage index name of area Flood discharge, in cubic feet per second, for number and record (square indicated recurrence interval, in years number (years) miles) 2 5 10 25 50 100 Lower Coastal Plain 29 Turkey Creek 18 14.8 405 753 11050 1,520 1,930 2,410 near Turkey, N.C. (02106240) 30 Stewarts 16 0.64 56 103 146 221 293 390 Creek Tribu- tary near Warsaw, N.C. (02106410) 31 Black River 33 676 3,720 5,920 79740 10,600 13,000 15,800 near Tomahawk, N.C. (02106500) 32 Big Swamp 20 31.9 544 1,100 1,640 2,600 3,490 4,540 near Roseboro, N.C. (02106910) 33 South River 33 379 29100. 3,290 4,230 5,660 69930 8,440 near Parkers- burg, N.C. (02107000) Table l.--Weighted flood discharges for selected recurrence intervals for rural streamflow stations used in the regionalization study--Continued Map Station Period Drainage index name of area Flood discharge, in cubic feet per second, for number and record (square indicated recurrenc6,interval, in years number (years) miles) 2 5 10 25 50 100 Lower Coastal Plain 34 Colly Creek 24 108 564 972 1,300 1,850 2,370 3,040 near Kelly, N.C. (02107500) 35 Rockfish 27 69.3 1,430 2@370 2,470 49340 5,320 69420 Creek near Wallace, N.C. (02108500) 36 Turkey Creek 19 10.5 309 677 19040 1,680 2,270 2,970 near Castle Hayne, N.C. (02108630) 37 Buckhead 19 14.7 405 704 964 1,380 1,750 2,190 Branch near Bolton, N.C. (02108960) Table l.--Weighted flood discharges for selected recurrence intervals for rural streamflow stations used in the regionalization study-Continued Map Station Period Drainage index name of area Flood discharge, in cubic feet per second, for number and record (square indicated recurrence interval, in years number (years) miles) 2 5 10 25 50 100 Lower Coastal Plain 38 Waccamaw 45 680 4,000 6,180 7,770 99960 11,700 13,700 River at Freeland, N.C. (02109500) 39 Wet Ash 18 16.2 417 785 1,100 1,600 2,040 2,570 Swamp near Ash, N.C. (02109640) 40 Mill Branch 18 3.52 151 317 471 732 964 1,250 near Tabor City, N.C. (02110020) Upper Coastal Plain 41 Juniper 18 64.0 399 704 974 1,430 1,900 2,430 Creek near Cheraw, S.C. (02130500) Table I.--Weighted flood discharges for selected recurrence intervals for rural streamflow stations used in the regionalization study--Continued Map Station Period Drainage index name of area Flood discharge, in cubic feet per second, for number and record (square indicated recurrence interval_, in years number (years) miles) 2 5 10 25 50 100 Upper Coastal Plain 42 Black Creek 29 108 733 1,080 1,300 1,600 1,840 2,070 near McBee, S.C. (02130900) 43 Little 49 524 2,500 3,900 4,960 6,440 7,700 8,960 Pee Dee River near Dillon, S.C. (02132500) 44 Scape Ore 20 96.0 687 1,040 1,310 1,660 1,960 2,240 Swamp near Bishopville, S.C. (02135300) 45 Colonel 14 40.2 304 518 692 942 1,162 1,385 Creek near Leesburg, S.C. (02148300) ble 1.--Weighted flood discharoes for selected recurrence intervals for rural streamflow stations used in the regionalization s@d --Continued Map Station Period Drainage index name of area Flood discharge, in cubic feet per second, for number and record (square indicated recurrence interval, in years number (years) miles) 2 5 10 25 50 100 Upper Coastal Plain - 46 Congaree 21 122 860 19200 1,450 1,800 2,100 2,370 Creek near Cayce, S.C. (02169550) 47 Big Beaver 22 10.1 94 180 272 417 538 671 Creek near St. Matthews, S.C. (02169630) 48 South Fork 44 198 1,540 .2,290. 2,820 3,500 4,060 4,590 Edisto River near Montmorenci, S.C. (02172500) 49 South Fork 56 720 2,600 3,980 5tlOO 6,750 8,220 9,750 Edisto River near Denmark, S.C. (02173000) Table l.--Weighted flood discharges for selected recurrence intervals for rural streamflow stations used in the regionalization study--Continued Map Station Period Drainage index name of area Flood discharge, in cubic feet per second, for number and record (square indicated recurrence interval, in years number (years) miles) 2 5 10 25 50 100 Upper Coastal Plain 50 North Fork 51 683 2,640 31970 49990 6,420 7,630 8,820 Edisto River at Orange- burg, S.C. (02173500) 51 Edisto 44 1,720 5,920 8,900 11,000 13t8OO 16,100 18,200 River near Branch- ville, S.C. (02174000) 52 Salkahatchie 38 341 1,530 2,240 2,740 3,410 3,960 4,460 River near Miley, S.C. (02175500) 53 McBean Creek 27 41.4 ____329- 557 741 1,000 1,220 1,470 near McBean, Ga. (02197190) Table l.--Weighted flood discharges for selected recurrence intervals for rural streamflow stations used in the regionalization study-Continued Map Station Period Drainage index name of area Flood discharge, in cubic feet per second, for number and record (square indicated recurrence interval, in years number (years) miles) 2 5 10 25 50 100 Upper Coastal Plain 54 Brushy Creek 31 28.0 402 625 793 1,010 1,200 1,400 near Wrens, Ga. (02197600) 55 Brier Creek 20 473 3,640 5,900 7,920 11,000 14,200 18,000 near Waynesboro, Ga. (02197830) 56 Big Creek 26 95.8 696 19200 1,580 2,090 2,520 2,970 near Louisville, Ga. (02200900) 57 Ogeechee 25 14.2 235 436 608 859 1,090 1,360 River Tributary near Louisville, Ga. (02200930) Table I.--Weighted flood discharges for selected recurrence intervals for rural streamflow stations used in the regionalization_2Lud --Continued I Map Station Period Drainage index name of area Flood discharge, in cubic feet per second, for number and record (square indicated recurrence interval, in years number (years) miles) 2 5 10 25 50 100 Upper Coastal Plain 58 Flat Creek 16 7.63 136 221 290 393 482 582 near Inverness, N.C. (02102908) 59 South Prong 19 7.57 123 207 272 373 465 562 Anderson Creek near Lillington, N.C. (02103390) 60 Little River 44 459 3,390 5,270 6@850 9,400 llp600 14,100 near Linden, N.C. (02103500) 61 Rockfish 16 292 2,020 3,430 4,600 6,520 8,150 10,000 Creek near Hope Mills, N.C. (02104500) Table l.--Weighted flood discharges for selected recurrence intervals for rural streamflow stations used in the,regionalization ud --Continued Map Station Period Drainage index name of area Flood discharge, in cubic feet per second, for number and record (square indicated recurrence interval,, in years number (years) miles) 2 5 10 25 50 100 Upper Coastal Plain 62 Bridge Creek 18 6.05 110 188 258 366 459 566 Tributary at Johns, N.C. (02132230) 63 Drowning 45 178 1,320 2,460 3,530 5,490 7,340 9,670 CO Creek near Hoffman, N.C. (02133500) 64 Beaverdam 18 4.42 81 130 161 210 254 293 Creek near Aberdeen, N.C. (02133590) 65 Tenmile Swamp 18 16.6 231 365 459 596 716 844 near Lumberton, N.C. (02134380) Table I.--Weighted flood discharges for selected recurrence intervals for rural streamflow stations used in the regionalization_aLudy--Continued Map Station Period Drainage index name of area Flood discharge, in cubic feet per second, for number and record (square indicated recurrence interval, in years number (years) miles) 2 5 10 25 50 100 Upper Coastal Plain 66 Lumber River 55 19228 4v2OO 79300 91900 14,100 17v5OO 21,600 at Boardman, N.C. (02134500) Piedmont 67 Fork Creek 12 24.3 649 1,170 19620 2v210 29690 3,180 near Jeffer- son, S.C. (02131309) 68 Rocky Creek 32 194 69610 9,760 11,900 149800 179300 209000 at Great Falls, S.C. (02147500) 69 Scabber 10 4.55 1,050 1,480 1,610 1,830 29020 2,250 Branch near Great Falls, S.C. (02147600) Table l.--Weiqhted flood discharges for selected recurrence intervals for rural streamflow stations used in the regionalization ILudy--Continued Map Station Period Drainage index name of area Flood discharge, in cubic feet per second, for number and record (square indicated recurrence interval, in years number (years) miles) 2 5 10 25 50 100 Piedmont 70 North 58 116 3,010 4,940 6,330 8,130 9,560 11,000 Pacolet River at Fingerville, S.C. CD (02154500) 71 North Tyger 38 44.4 1,360 2@180 2,770 3,530 4,130 4,740 River near Fairmont, S.C. (02157000) 72 Middle Tyger 42 68.3 2,510 3,220 3,690 4,310 4,820 5,340 River at Lyman, S.C. (02157500) 73 North Tyger 41 162 3,730 5,920 7,490 9,520 11,200 12,900 River near Moore, S.C. (02158000) Table I.--Weighted flood discharges for selected recurrence intervals for rural streamflow stations used in the regionalization study--Continued Map Station Period Drainage index name of -area Flood discharge, in cubic feet per second, for number and record Cs@udre indicated recurrence interval, in years number (years) miles) 2 5 10 25 50 100 Piedmont 74 South Tyger 41 106 2,460 3,780 4,780 6,100 7,190 8,320 River near Reidville, S.C. (02158500) 75 South Tyger 44 174 2,910 4,810 6,320 8,370 10,100 11,800 River near Woodruff, S.C. (02159000) 76 Tyger River 28 351 6,480 11,500 15,200 20,200 24,400 28,900 near Woodruff, S.C. (02159500) 77 Fairforest 49 183 3,990 5,890 7,120 8,610 9,780 10,900 Creek near Union, S.C. (02160000) 78 Tyger River 15 759 10,300 15,400 19,200 23,800 27,800 31,900 Delta, S.C. (02160105) Table i.--Weighted flood discharges for selected recurrence intervals for rural streamflow stations used in the regionalization study--Continued Map Station Period Drainage index name of area Flood discharge, in cubic feet per second, for number and record (square indicated recurrence interval, in years number (years) miles) 2 5 10 25 50 100 Piedmont 79 Enoree River 59 307 6,220 10,000 12,700 16,300 19,300 22,400 near Enoree, S.C. (02160500) 80 Enoree River 15 444 5,570 9,070 12,000 15,700 18,800 22,100 near Whitmire, S.C. (02160700) 81 Cedar Creek 21 48.9 29700 3,690 4,050 4,470 4,840 5,310 near Blythe- wood, S.C. (02162010) 82 Saluda River 43 295 4,580 6,590 8,080 10,000 11,600 13,200 near Green- ville, S.C. (02162500) 83 Saluda 57 405 6,380 8,960 10,700 12,900 14,700 16,400 River near Pelzer, S.C. (02163000) Table i.--Weighted flood discharges for selected recurrence intervals for rural streamflow stations used in the regionalization_aLudy--Continued Map Station Period Drainage index name of area Flood discharge, in cubic feet per second, for number and record (square indicated recurrence interval, in years number (years) miles) 2 5 10 25 50 100 Piedmont 84 Saluda River 50 581 9,160 13,500 16,300 19,600 22,100 24,700 near Ware Shoals, S.C. (02163500) 85 Reedy River 49 236 4,300 6,720 8,440 10,600 12,400 14,100 near Ware Shoals, S.C. (02165000) 86 South Rabon 15 29.9 832 1,600 2,220 3@040 3,700 4,390 Creek near Gray Court, S.C. (02165200) 87 Twelvemile 10 106 3,120 4,100 4,930 69030 7,020 8,040 Creek near Liberty, S.C. (02186000) 88 Broadway 10 26.4 968 1,560 1,990 2,550 3,020 3,480 Creek near .Anderson, S.C. (02187900) Table l.--Weighted flood discharges for selected recurrence intervals for rural streamflow stations used in the regionalization study--Continued Map Station Period Drainage index name of area Flood discharge, in cubic feet per second, for number and record (square indicated recurrence interval, in years number (years) miles) 2 5 10 25 50 100 Piedmont 89 Rocky River 27 267 4,590 7,500 9,570 12,100 14,200 16,300 near Calhoun Falls, S.C. (02188000) 90 Little River 46 217 4t720 7,400 9,320 11,800 13,800 15,900 v,n near Mt. Carmel, S.C. (02192500) 91 Stevens Creek 45 545 12,400 18,200 21t700 25,800 29,100 32,500 near Modoc, S.C. (02196000) 92 South 35 35.8 1,390 2,350 3,130 4,240 5t190 6t180 Beaverdam Creek at Dewy Rose, Ga. (02188500) 93 Indian Creek 13 7.63 738 1,130 lt440 19850 2,200 2,550 near Carnes- ville, Ga. (02189020) Table i.--Weighted flood discharges for selected recurrence intervals for rural streamflow stations used in the regionalization study--Continued Map Station Period Drainage index name of area Flood discharge, in cubic feet per second, for number and record (square indicated recurrence interval, in years number (years) miles) 2 5 10 25 50 100 Piedmont 94 Stephens 13 0.39 110 169 213 274 322 373 Creek Tri- butary at Carnes- ville, Ga. (02189030) - 95 Bear Creek 13 3.62 398 717 973 1,330 1,640 1,960 near Mize, Ga. (02189600) 96 Toms Creek 13 3.79 486 833 19110 19520 lt870 29240 near Eastanollee, Ga. (02190100) 97 Toms Creek 14 1.20 317 489 605 763 890 ltO2O Tributary near Avalon, Ga. (02190200) Table l.--Weighted flood discharges for selected recurrence intervals for rural streamflow stations used in th_eregionalization_@ @ud --Continued Map Station Period Drainage index name of area Flood discharge, in cubic feet per second, for number and record (square indicated recurrence interval, in years number (years) miles) 2 5 10 25 50 100 Piedmont 98 Double 16 0.50 174 283 - 359 466 551 642 Branch at Bowers- ville, Ga. (02190800) %.n or\ 99 North Fork 15 119 3,600 6,070 8,030 10,700 13,000 15,200 Broad River near Carnes- ville, Ga. (02191000) 100 Hudson River 29 61.1 2,280 3,910 5,160 6,660 8,280 9,680 at Homer, Ga. (02191200) 101 Scull Shoal 12 8.75 633 1,170 1,580 2,140 2,610 39070 Creek near Daniels- ville, Ga. (02191270) 102 Mill Shoal 25 0.32 110 174 217 273 315 358 Creek near Royston, Ga. (02191280) Table l.--Weighted flood discharges for selected recurrence intervals for rural streamflow stations used in the regionalization study-Continued Map Station Period Drainage index name of area Flood discharge, in cubic feet per second, for number and record (square indicated recurrence interval, in years number (years) miles) 2 5 10 25 50 100 Piedmont 103 Broad River 89 760 13,200 22tOOO 28,500 37,300 44,600 52,000 above Carlton, Ga. (02191300) 104 Double Branch 13 4.77 451 827 1,130 1,540 1,890 2,250 near Daniels- ville, Ga. (02191600) 105 Fork Creek 12 13.8 857 lt370 1,780 2,320 2,770 3,220 at Carlton, Ga. (02191750) 106 Brooks Creek 12 12.3 1,010 1,840 2,440 3,230 3,890 4,520 near Lexington, Ga. (02191890) 107 Trouble 17 2.70 166 307 431 610 758 918 Creek at Lexington, Ga. (02191910) Table 1.--Weighted flood discharges for selected recurrence intervals for rural streamflow stations used in the reqionalization study--Continued Map Station Period Drainage index name of area Flood discharge, in cubic feet per second, for number and record (square indicated recurrence interval, in years number (years) miles) 2 5 10 25 50 100 Piedmont 108 Buffalo 25 5.79 476 834 1,120 1,550 9io 2,290 Creek near Lexington, Ga. (02191930) CO 109 Macks Creek 17 3.45 221 423 604 870 1,100 1,340 near Lexington, Ga. (02191960) 110 Little Macks 27 1.77 188 352 485 675 829 994 Creek Tributary near Lexington, Ga. (02191970) ill Broad River 59 1,430 21,700 31,800 38,700 47,300 54,200 60,500 near Bell, Ga. (02192000) Table l.--Weiqhted flood discharges for selected recurrence intervals for rural streamflow stations used in the-regionalizatibn_lLudy--Continued Map Station Period Drainage index name of area Flood discharge, in cubic feet per second, for number and record (square indicated recurrence interval, in years number (years) miles) 2 5 10 25 50 100 Piedmont 112 Hog Fork 31 0.10 43 74 96 125 148 171 Fishing Creek Tributary near Tignall, Ga. (02192300) 113 Anderson 12 5.49 552 929 lt2lO 1,580 1,870 2J60 Mill Creek near Danburg, Ga. (02192400) 114 Anderson 12 0.92 151 297 410 565 690 821 Mill Creek Tributary near Danburg, Ga. (02192420) 115 Stephens 12 6.30 750 1,180 1,500 1,960 2,350 2,740 Creek near Crawford- ville, Ga. (02193300) Table i.--Weighted flood discharges for selected recurrence intervals for rural streamflow stations used in the regionalization study--Continued Map Station Period Drainage index name of area Flood discharge, in cubic feet per second, for number and record (square indicated recurrence interval, in years number (years) miles) 2 5 10 25 50 100 Piedmont 116 Harden Creek 12 3.98 480 750 953 1,230 1,460 1,680 near Sharon, Ga. (02193400) 117 Little River 22 291 6,390 10,600 13,700 17,400 20,400 23,100 near Washing- ton, Ga. (02193500) 118 Rocky Creek 12 1.14 328 464 556 686 790 897 near Washing- ton, Ga. (02193600) 119 North Prong 20 3.63 537 1,010 1,380 1,990 2,460 3,000 Creek near Hunters- ville, N.C. (02124060) Table l.--Weighted flood discharges for selected recurrence intervals for rural streamflow stations used in the regionalization study -Continued Map Station Period Drainage index name of area Flood discharge, in cubic feet per second, for number and record (square indicated recurrence interval, in years number (years) miles) 2 5 10 25 50 100 Piedmont 120 Mallard 18 20.6 1,600 29350 2,900 3,690 4,360 5,120 Creek near Charlotte, N.C. (02124130) ON 121 Big Bear 30 55.6 4t680 7pOOO 8@330 lOp3OO 11,600 13,000 near Rich- field, N.C. (02125000) 122 Chinkapin 18 8.40 19320 2,150 2,610 3,360 3t850 4,390 Creek near Monroe, N.C. (02125410) 123 Rocky River 55 19372 329700 46,300 54,700 65,500 73,400 81,300 near Norwood, N.C. (02126000) 124 Brown Creek 36 110 2,190 4,150 6,060 9,180 12,100 15,700 near Polkton, N.C. (02127000) Table l.--Weighted flood discharges for selected recurrence intervals for rural streamflow stations used in the regionalization study--Continued Map Station Period Drainage index name of area Flood discharge, in cubic feet per second, for number and record (square indicated recurrence interval, in years number (years) miles) 2 5 10 25 50 100 Piedmont 125 Palmetto 17 0.86 174 274 348 459 550 651 Branch near Ansonville, N.C. (02127390) 126 Little River 30 106 4,030 5,680 6,900 8,560 9,980 11,500 near Star, N.C. (02128000) 1 127 Cheek Creek 18 15.5 978 1,700 2,330 3,340 4,230 5,260 near Pekin, N.C. (02128260) 128 South Fork 18 16.2 854 1,240 1,590 2,050 2,480 2,980 Jones Creek near Morven, N.C. (02129440) Table l.--Weighted flood discharges for selected recurrence intervals for rural streamflow stations used in the reqionalization_@ @ud --Continued Map Station Period Drainage index name of area Flood discharge, in cubic feet per second, for number and record (square indicated recurrence interval, in years number (years) miles) 2 5 10 25 50 100 Piedmont 129 Hagan Creek 15 8.46 812 1,370 1,780 2,460 29990 3,600 near Catawba, N.C. (02142480) 130 Henr Fork 48 83.2 4,920 8,460 11,200 15,700 19,500 23,600 y near Henry River, N.C. (02143000) 131 Jacob Fork 23 25.7 2,190 3,480 4,350 5,710 6,760 7,900 at Ramsey, N.C. (02143040) 132 Indian Creek 33 69.2 2,220 3,810 5,190 7,260 99080 11,100 near Labora- tory, N.C. (02143500) 133 Long Creek 31 31.8 1,500 2,530 3,440 4,860 6,130 79610 near Bessemer Cityq N.C. (02144000) Table l.--Weighted flood discharges for selected recurrence intervals for rural streamflow stations used in the regionalization_2Lud@--Continued Map Station Period Drainage index name of area Flood discharge, in cubic feet per second, for number and record (square indicated recurrence interval, in years number (years) miles) 2 5 10 25 50 100 Piedmont 134 South Fork 30 628 10,100 15,300 19,600 25,700 31,000 36,800 Catawba River at Lowell, N.C. (02145000) 135 East Fork 18 42.3 2,280 3,170 3,850 4,830 5,720 6,720 Twelve Mile Creek near Waxhaw, N.C. (02146890) 136 Twelve Mile 24 76.5 3,070 41570 5,660 7,110 8,340 9,680 Creek near Waxhaw, N.C. (02146900) 137 Cove Creek 33 79.0 3,060 4,680 5,800 7,290 8,490 9,770 near Lake Lure, N.C. (02149000) 138 Camp Creek 17 12.2 638 1,000 1,320 1,710 2,080 2,500 near Ruther- fordton, N.C. (02150420) Table i.--Weighted flood discharges for selected recurrence intervals for rural streamflow stations used in the regionalization_2Ludy--Continued Map Station Period Drainage index name of area Flood discharge, in cubic feet per second, for number and record (square indicated recurrence interval, in years number (years) miles) 2 5 10 25 50 100 Piedmont 139 Broad River 58 875 16,800 25,900 32,800 42,400 50,400 59,100 near Boiling Springs, N.C. (02151500) 140 First Broad 25 60.5 2,990 4,750 6,010 7,800 9,200 10,700 River near Casar, N.C. (02152100) 141 Big Knob 18 15.8 1,050 1,660 2,150 2@890 3,530 4,250 Creek near Fallston, N.C. (02152420) 142 First Broad 39 200 6,710 9,640 11,800 15-,00 17,600 20,500 River near Lawndale, N.C. (02152500) Table l.--Weighted flood discharges for selected recurrence intervals for rural streamflow stations used in the regionalization sWdy--Continued Map Station Period Drainage index name of area Flood discharge, in cubic feet per second, for number and record (square indicated recurrence interval, in years number (years) miles) 2 5 10 25 50 100 Piedmont 143 Sugar Branch 31 1.42 373 595 744 953 1,100 1,270 near Boiling Springs, N.C. (02152610) Blue Ridge 144 Whitewater 16 48.5 2,960 4,300 5,280 6,740 8,090 9,380 River at Jocassee, S.C. (02184500) 145 Keowee River 18 148 8,750 12,400 14,700 18,000 21,200 24,000 near Jocasee, S.C. (02185000) Table I.--Weighted flood discharges for selected recurrence intervals for rural streamflow stations used in the regionalization_@ @ud --Continued Map Station Period Drainage index name of area Flood discharge, in cubic feet per second, for number and record (square indicated recurrence interval, in years number (years) miles) 2 5 10 25 50 100 Blue Ridge 146 Little River 21 72.0 3,560 6,410 8,470 11,400 14,100 16,700 near Walhalla, S.C. (02185200) 147 Seneca 22 455 16,100 20,200 22,900 26,500 29,800 32,300 River near Newry, S.C. (02185500) 148 Chattooga 50 207 7,320 11,700 15,000 20,100 24,300 28,800 River near Clayton, Ga. (02177000) 149 Chattooga 13 256 9,040 14,200 17,700 22,900 27,400 30,900 River near Tallulah Falls, Ga. (02178000) Table l.--Weighted flood discharges for selected recurrence intervals for rural streamflow stations used in the regionalization study--Continued Map Station Period Drainage index name of area Flood discharge, in cubic feet per second, for number and record (square indicated recurrence interval, in years number (years) miles) 2 5 10 25 50 100 Blue Ridge 150 Tallulah 24 56.5 2,800 4,560 5,820 7,550 8,930 10,300 River near Clayton, Ga. (02178400) 151 Little 19 2.50 139 291 433 642 830 1,040 CO Panther Creek near Tallulah Falls, Ga. (02181800) 152 Panther 50 32.5 2,230 4,510 6,370 9,220 11,600 14,200 Creek near Toccoa, Ga. (02182000) 153 Chattahoochee 49 150 6,860 10,600 13,100 16,300 18,800 21,100 River near Leaf, Ga. (02331000) Table l.--Weighted flood discharges for selected recurrence intervals for rural streamflow stations used in the regionalization_jLudy--Continued Map Station Period Drainage index name of area Flood discharge, in cubic feet per second, for number and record (square indicated recurrence interval, in years number (years) miles) 2 5 10 25 50 100 Blue Ridge 154 Soque River 26 156 5,640 8,980 11,400 14,800 17,500 20,300 near Demorest, Ga. (02331500) 155 Chattahoochee 49 315 11,600 17,400 21,100 25,800 29,300 32,400 River near Corneila, Ga. (02331600) 156 Hiwassee River 42 45.5 1,990 3,200 4,090 5,270 6,210 7,150 at Presley, Ga. (03545000) 157 French Broad 51 67.9 4,050 5@980 79320 9,170 10,700 12,200 River at Rosman, N.C. (03439000) Table i.--WQighted flood discharges for selected recurrence intervals for rural streamflow stations used in the regionalization study--Continued Map Station Period Drainage index name of area Flood discharge, in cubic feet per second, for number and record (square indicated recurrence interval, in years number (years) miles) 2 5 10 25 50 100 Blue Ridge 158 French Broad 31 103 4,590 7,060 8,840 11,500 13,600 15,900 River at Calvert, N.C. (03439500) 159 Catheys Creek 11 11.4 615 1,060 1,440 2,000 2,500 3,100 near Brevard, N.C. (03440000) 160 Davidson 64 40.4 2,750 4,220 5,220 6,580 7,610 8,700 River near Brevard, N.C. (03441000) 161 Little River 22 26.8 1,650 2,660 3,390 4,430 5,270 6,180 above High Falls near Cedar Mountain N.C. (03441440) Table l.--Weighted flood discharges for selected recurrence intervals for rural streamflow stations used in the regionalization@udy--Continued Map Station Period Drainage index name of area Flood discharge, in cubic feet per second, for number and record (square indicated recurrence interval, in years number (years) miles) 2 5 10 25 50 100 Blue Ridge 162 Crab Creek 13 10.9 564 965 1,360 1,950 2,500 3,140 near Penrose, N.C. (03442000) 163 French Broad 64 296 7,010 11,200 14,600 19,900 24,400 29,600 River at Blantyre, N.C. (03443000) 164 South Fork 31 9.99 644 11110 1,520 2,160 2,740 3,420 Mills River at The Pink Beds, N.C. (03444500) 165 Mills River 52 66.7 2t540 4,030 5,240 7,000 8,510 10,200 near Mill River, N.C. (03446000) Table 1'.--Weighted flood discharges for selected recurrence intervals for rural streamflow stations used in regionalization_@ @ud --Continued Map Station Period Drainage index name of area Flood discharge, in cubic feet per second, for number and record (square indicated recurrence interval, in years number (years) miles) 2 5 10 25 50 100 Blue Ridge 166 Laurel Branch 12 0.57 82 117 150 188 234 288 near Edneyville, N.C. (03446410) 167 Cedar Creek 10 42.2 1,560 2,730 3,790 5,370 6,760 8,320 near Henderson- ville, N.C. (03446500) 168 French 50 676 11,100 15,800 19,600 24,600 28,900 33,600 Broad River at Bent Creek, N.C. (03448000) 169 Hominy 35 79.8 2,020 3,620 5,130 7,550 9,820 12,500 Creek at Candler, N.C. (03448500) Table l.-Weighted flood discharges for selected recurrence intervals for rural streamflow stations used in the regionalization_2Ludl--Continued Map Station Period Drainage index name of area Flood discharge, in cubic feet per second, for number and record (square indicated recurrence interval, in years number (years) miles) 2 5 10 25 50 100 Blue Ridge 170 North Fork 27 24.0 1,780 3p420 4,890 7,500 9,710 12,400 Swannanoa River near Black Mountain, N.C. (03449000) 171 Beetree Creek 51 5.46 246 420 585 842 1,090 1,390 near Swannonoa, N.C. (03450000) 172 Swannonoa 55 130 3,000 5,230 7,340 11,800 14,100 17,900 River near Biltmore, N.C. (03451000) 173 French Broad 89 945 15,000 22,200 27,900 35,800 42,500 49,900 River at Asheville, N.C. (03451500) Table i.--Weighted flood discharges for selected recurrence intervals for rural streamflow stations used in the regionalization study--Continued Map Station Period Drainage index name of area Flood discharge, in cubic feet per second, for number and record (square indicated recurrence interval, in years number (years) miles) 2 5 10 25 50 100 Blue Ridge 174 Cullasaja 44 14.9 997 1,620 2,130 2,930 3@630 4,420 River'at Highlands, N.C. (03500500) 3 6668 00003 3524