Prepared in cooperation with the Spartanburg Water System Limnological Conditions in Lake William C. Bowen and Municipal Reservoir #1, Spartanburg County, South Carolina, August to September 2005, May 2006, and October 2006 Open-File Report 2008–1268 U.S. Department of the Interior U.S. Geological Survey Cover photograph. Northern shoreline of Lake William C. Bowen below Interstate-26 bridge. Limnological Conditions in Lake William C. Bowen and Municipal Reservoir #1, Spartanburg County, South Carolina, August to September 2005, May 2006, and October 2006 By Celeste A. Journey and Thomas A. Abrahamsen Prepared in cooperation with the Spartanburg Water System Open-File Report 2008–1268 U.S. Department of the Interior U.S. Geological Survey U.S. Department of the Interior DIRK KEMPTHORNE, Secretary U.S. Geological Survey Mark D. Myers, Director U.S. Geological Survey, Reston, Virginia: 2008 For product and ordering information: World Wide Web: http://www.usgs.gov/pubprod Telephone: 1-888-ASK-USGS For more information on the USGS--the Federal source for science about the Earth, its natural and living resources, natural hazards, and the environment: World Wide Web: http://www.usgs.gov Telephone: 1-888-ASK-USGS 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. Suggested citation: Journey, C.A., and Abrahamsen, T.A., 2008, Limnological conditions in Lake William C. Bowen and Municipal Reservoir #1, Spartanburg County, South Carolina, August to September 2005, May 2006, and October 2006: U.S. Geological Survey Open-File Report 2008–1268, 96 p. iii Contents Abstract ...........................................................................................................................................................1 Introduction.....................................................................................................................................................2 Purpose and Scope ..............................................................................................................................4 Description of Study Area ...................................................................................................................4 Previous Investigations........................................................................................................................7 Approach and Methods ................................................................................................................................9 Data Collection ......................................................................................................................................9 Data Analysis .......................................................................................................................................12 Quality Assurance...............................................................................................................................14 Limnological Conditions ..............................................................................................................................14 Stratification ........................................................................................................................................14 Nutrient and Chlorophyll a Levels ...................................................................................................15 Spatial and Temporal Variation................................................................................................22 Comparison to Numerical Criteria and Guidelines ...............................................................32 Trophic Status ......................................................................................................................................33 Wastewater Indicator Compound Occurrence .............................................................................34 Geosmin and MIB Occurrence .........................................................................................................42 Phytoplankton Community Structure ...............................................................................................43 Summary........................................................................................................................................................50 Acknowledgments .......................................................................................................................................52 References ....................................................................................................................................................52 Appendix A. National Land Cover Database (NLCD) Land Cover Classification System Key and Definitions .....................................................................57 Appendix B. Laboratory Reporting Levels and Method Descriptions for Selected Analytes in Water Samples Collected from Lake William C. Bowen and Municipal Reservoir #1, Spartanburg County, South Carolina ..........................................................................................59 Appendix C. Phytoplankton Taxonomy at selected sites in Lake William C. Bowen and Municipal Reservoir #1, Spartanburg County, South Carolina, August 2005 to October 2006 ........................................................................................................67 iv Figures 1. Map showing location of Lake William C. Bowen and Municipal Reservoir #1 in Spartanburg County, South Carolina .....................................................................................3 2. Graph showing land-use change in the South Pacolet River basin, Spartanburg County, South Carolina, from 1982 to 2001 .......................................................7 3. Map showing transect locations in Lake William C. Bowen and Municipal Reservoir #1, Spartanburg County, South Carolina, 2005–2006...........................................10 4–12. Graphs showing— 4. Depth profiles of temperature, pH, specific conductance, and dissolved oxygen at the mid-point of sites (A) LWB-5, (B) LWB-8, (C) LWB-10, and (D) MR1-14 in Lake William C. Bowen and Municipal Reservoir #1, Spartanburg County, South Carolina, August–September 2005 .................................17 5. Depth profiles of temperature, pH, specific conductance, dissolved oxygen, and chlorophyll a at the mid-point of sites (A) LWB-5, (B) LWB-8, (C) LWB-10, and (D) MR1-14 in Lake William C. Bowen and Municipal Reservoir #1, Spartanburg County, South Carolina, May 2006 ..........18 6. Depth profiles of temperature, pH, specific conductance, dissolved oxygen, and chlorophyll a at the mid-point of sites (A) LWB-8, (B) LWB-10, (C) MR1-12, and (D) MR1-14 in Lake William C. Bowen and Municipal Reservoir #1, Spartanburg County, South Carolina, October 2006 ..............................20 7. Concentrations of (A) total Kjeldahl nitrogen, (B) total phosphorus, (C) ammonia, and (D) chlorophyll a in samples from near the surface (1-meter depth) and near the bottom (between 2.5 and 7 meters) at selected sites in Lake William C. Bowen and Municipal Reservoir #1, Spartanburg County, South Carolina, August 30–September 15, 2005 .......................23 8. Concentrations of (A) total Kjeldahl nitrogen, (B) total phosphorus, (C) nitrate plus nitrite, and (D) chlorophyll a in samples from near the surface (1-meter depth) and near the bottom (6-meter depth) at selected sites in Lake William C. Bowen and Municipal Reservoir #1, Spartanburg County, South Carolina, May 15–17, 2006 .................................................29 9. Concentrations of (A) total Kjeldahl nitrogen, (B) total phosphorus, (C) ammonia, and (D) chlorophyll a in samples from near the surface (1-meter depth) and near the bottom (6-meter depth) at selected sites in Lake William C. Bowen and Municipal Reservoir #1, Spartanburg County, South Carolina, October 24–25, 2006 ................................................................................31 10. Concentrations of (A) chlorophyll a, (B) total phosphorus, (C) values of transparency, and (D) ratios of total nitrogen to total phosphorus in samples collected near the lake surface along with established criteria and guidelines at selected sites in Lake William C. Bowen and Municipal Reservoir #1, Spartanburg County, South Carolina for August–September 2005, May 2006, and October 2006 ................................................32 11. Computed Carlson trophic state indices (TSI) for (A) chlorophyll a, (B) total phosphorus, and (C) transparency for selected sites and (D) average of all sites in Lake William C. Bowen and Municipal Reservoir #1, Spartanburg County, South Carolina, August–September 2005, May 2006, and October 2006 ................................................35 12. Concentrations of geosmin near the surface (1-meter depth) and near the bottom (2.5 to 7 meters depth) at selected sites in Lake William C. Bowen and Municipal Reservoir #1 in (A) August to September 2005, (B) May 2006, and (C) October 2006 and (D) in raw and finished water at R.B. Simms water treatment plant in Spartanburg County, South Carolina ...............................................43 v Tables 1. Physical characteristics of Lake William C. Bowen and Municipal Reservoir #1, Spartanburg County, South Carolina