Low-flow frequency and flow duration of selected South Carolina streams in the Broad River basin through March 2008

Abstract

For more information on the USGS-the Federal source for science about the Earth, its natural and living resources, natural hazards, and the environment, visit http://www.usgs.gov or call 1-888-ASK-USGS For an overview of USGS information products, including maps, imagery, and publications, visit http://www.usgs.gov/pubprodTo order this and other USGS information products, visit http://store.usgs.gov Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.Although this report is in the public domain, permission must be secured from the individual copyright owners to reproduce any copyrighted materials contained within this report. Vertical coordinate information is referenced to the National Geodetic Vertical Datum of 1929 (NGVD 29).Horizontal coordinate information is referenced to the North American Datum of 1983 (NAD 83). Acronyms and Abbreviations Used in the Report AbstractIn 2008, the U.S. Geological Survey, in cooperation with the South Carolina Department of Health and Environmental Control, initiated a study to update low-flow statistics at continuous-record streamgaging stations operated by the U.S. Geological Survey in South Carolina. This report presents the low-flow statistics for 23 selected streamgaging stations in the Broad River basin in South Carolina, and includes flow durations of 5-, 10-, 25-, 50-, 75-, 90-, and 95-percent probability of exceedance and the annual minimum 1-, 3-, 7-, 14-, 30-, 60-, and 90-day mean flows with recurrence intervals of 2, 5, 10, 20, 30, and 50 years, depending on the length of record available at the streamgaging station. The low-flow statistics were computed from records available through March 31, 2008. In addition, flow duration information is presented for one streamgaging station 021556525, Pacolet River below Lake Blalock near Cowpens, SC, where recurrence interval computations were not appropriate.Of the 23 streamgaging stations for which recurrence interval computations were made, 14 had low-flow statistics that were published in previous U.S. Geological Survey reports. A comparison of the low-flow statistics for the minimum mean flow for a 7-consecutive-day period with a 10-year recurrence interval (7Q10) from this study with the most recently published values indicated that 8 of the 14 stream gaging stations had values that were within plus or minus 25 percent of the previous value. Ten of the 14 streamgaging stations had negative percent differences indicating the low-flow statistic had decreased since the previous study, and 4 streamgaging stations had positive percent differences indicating that the low-flow statistic had increased since the previous study. The low-flow statistics are influenced by length of record, hydrologic regime under which the record was collected, techniques used to do the analysis, and other changes, such as urbanization, diversions, and so on, that may have occurred in the basin.

Low-flow frequency and flow duration of selected South Carolina streams in the Saluda, Congaree, and Edisto River basins through March 2009

“…Therefore, low-flow statistics were computed for stations 02164000, 02165200, 02167582, 02169570, 02173051, 02174250, and 02175000 using the complete period of record for each station, respectively. Similar patterns also have been noted in the low-flow assessments for the Pee Dee River and Broad River basins (Feaster and Guimaraes, 2009;Guimaraes and Feaster, 2010).…”

“…Previous reports by Stallings (1967), Johnson and others (1968), Bloxham and others (1970), Bloxham (1976Bloxham ( , 1979Bloxham ( , 1981, Barker (1986), Zalants (1991a,b), Feaster and Guimaraes (2009), and Guimaraes and Feaster (2010), described the low-flow frequency and flow-duration streamflows for selected CR stations and partial-record (PR) stations in South Carolina. Stallings (1967) presented low-flow statistics for 61 CR stations and 83 other sites where flow was measured during the 1954 drought.…”

“…Zalants (1991b) provided estimates of annual minimum 1-, 3-, 7-, 14-, 30-, 60-, and 90-day average streamflows with recurrence intervals of 2 to 50 years, depending on the length of record, for 55 CR stations in South Carolina for which at least 5 years of unregulated daily mean streamflow data were available through the 1986 CY. Feaster and Guimaraes (2009), and Guimaraes and Feaster (2010), presented low-flow statistics for 17 and 23 CR stations in the Pee Dee and Broad River basins in South Carolina, respectively. Estimates are presented for the Pee Dee River basin through the 2006 CY and for the Broad River basin through the 2007 CY.…”

“…In addition, daily flow durations of the 5-to 95-percent exceedances were presented for most of these stations. Much of the general information for this report was taken directly from Feaster and Guimaraes (2009) and Guimaraes and Feaster (2010).…”

Low-flow frequency and flow duration of selected South Carolina streams in the Catawba-Wateree and Santee River Basins through March 2012

“…Previous reports by Stallings (1967), Johnson and others (1968), Bloxham and others (1970), Bloxham (1976Bloxham ( , 1979Bloxham ( , 1981, Barker (1986), Zalants (1991a, b), Guimaraes (2009, 2012), and Guimaraes and Feaster (2010) described the low-flow frequency and flow-duration streamflows for selected CR stations in South Carolina. Stallings (1967) presented low-flow statistics for 61 CR stations and 83 other sites where flow was measured during the 1954 drought.…”