E. coli Total Maximum Daily Loads - Bitter and Killpecker Creeks, Wyoming March 14, 2018 E. coli Total Maximum Daily Loads - Bitter and Killpecker Creeks, Wyoming January 29, 2018 PREPARED BY PREPARED FOR Tetra Tech, Inc. Wyoming Department of Environmental P.O. Box 11895 Quality Jackson, WY 83002 Water Quality Division 200 West 17th Street Cheyenne, WY 82002 ACKNOWLEDGEMENTS DEQ would like to acknowledge the Sweetwater County Conservation District, the Bitter Creek- Killpecker Creek Watershed Advisory Group (BKWAG), and Environmental Design Engineering (EDE) for their contributions to the development of the TMDLs contained in this document. Page ii of x CONTENTS 1.0 INTRODUCTION AND PROBLEM IDENTIFICATION ........................................................................................1 2.0 WATERSHED DESCRIPTION .............................................................................................................................3 3.0 WATERSHED HYDROLOGY ..............................................................................................................................7 4.0 WATER QUALITY STANDARDS AND TARGETS .......................................................................................... 14 4.1 Applicable Water Quality Standards ........................................................................................................... 14 4.2 TMDL targets .............................................................................................................................................. 15 5.0 WATER QUALITY ............................................................................................................................................. 16 5.1 Bitter Creek ................................................................................................................................................. 16 5.1.1 Primary Contact Recreation .............................................................................................................. 16 5.1.2 Secondary Contact Recreation ......................................................................................................... 20 5.2 Killpecker Creek .......................................................................................................................................... 21 5.2.1 Primary Contact Recreation .............................................................................................................. 21 5.2.2 Secondary Contact Recreation ......................................................................................................... 24 6.0 SOURCE ASSESSMENT ................................................................................................................................. 25 6.1 Pathways ..................................................................................................................................................... 25 6.2 Potentially Significant Sources of Bacteria ................................................................................................. 27 6.3 Point Sources .............................................................................................................................................. 28 6.3.1 Superior Wastewater Lagoon (WY0021806) ..................................................................................... 30 6.3.2 B & R Mobile Home Village (WY0022128) ........................................................................................ 31 6.3.3 Rock Springs Water Reclamation Facility (WY0022357) .................................................................. 32 6.3.4 Stansbury Mine (WY0023825) .......................................................................................................... 33 6.3.5 Leucite Hills Mine (WY0028886) ....................................................................................................... 33 6.3.6 Black Butte Mine (WY0030261) ........................................................................................................ 33 6.3.7 Jim Bridger Mine (WY0030350) ........................................................................................................ 33 6.3.8 BLM Rock Springs Wild Horse Facility (WY0094528) ...................................................................... 33 6.3.9 Point of Rocks Lagoons (No Permit) ................................................................................................. 34 6.3.10 Reliance Facultative Lagoons (No Permit) ...................................................................................... 34 6.3.11 Summary ......................................................................................................................................... 35 6.4 Nonpoint Sources ........................................................................................................................................ 37 6.4.1 Septic Systems .................................................................................................................................. 37 6.4.2 Livestock ............................................................................................................................................ 38 6.4.3 Wild Horses ....................................................................................................................................... 40 Page iii of x 6.4.4 Wildlife ............................................................................................................................................... 42 6.4.5 Pets .................................................................................................................................................... 49 7.0 TMDL CALCULATIONS AND ALLOCATIONS TO SOURCES ...................................................................... 50 7.1 Total Maximum Daily Load.......................................................................................................................... 50 7.2 Loading Capacity ........................................................................................................................................ 51 7.3 Load Allocations .......................................................................................................................................... 52 7.4 Wasteload Allocations ................................................................................................................................. 52 7.5 Margin of Safety .......................................................................................................................................... 52 7.6 Seasonality .................................................................................................................................................. 52 8.0 MONITORING STRATEGY ............................................................................................................................... 53 8.1 Trend Monitoring ......................................................................................................................................... 53 8.2 Flow Monitoring ........................................................................................................................................... 53 8.3 Source Sampling ......................................................................................................................................... 54 8.4 Point Sources .............................................................................................................................................. 54 8.5 BMP Tracking and Effectiveness Monitoring .............................................................................................. 54 9.0 RESTORATION STRATEGY ............................................................................................................................ 55 9.1 Point Sources .............................................................................................................................................. 55 9.2 Septic Systems ........................................................................................................................................... 55 9.3 Pets ............................................................................................................................................................. 55 9.4 Livestock ..................................................................................................................................................... 55 9.5 Wild Horse ................................................................................................................................................... 56 9.6 Wildlife ......................................................................................................................................................... 56 9.7 Coordination with the Rock Springs Beautification Committee................................................................... 56 10.0 PUBLIC PARTICIPATION SUMMARY .......................................................................................................... 56 11.0 REFERENCES ................................................................................................................................................ 58 APPENDICES Appendix A. Summary of Available Hydrology Data Appendix B. Water Quality Data and Analysis Appendix C. Wild Horse Census and Flight Paths Appendix D. Response to Public Comments Page