FINAL DRAFT TOTAL MAXIMUM DAILY LOAD (TMDL) FOR THE RIO RUIDOSO NOVEMBER 3, 2016 Prepared by New Mexico Environment Department, Surface Water Quality Bureau, Monitoring, Assessment, and Standards Section Public Draft released August 22, 2016 Revised [date] Water Quality Control Commission Approval date: [date] Effective Date: [date] Revision Dates: [dates] For additional information please visit: www.nmenv.state.nm.us/swqb ~or~ 1190 St. Francis Drive Santa Fe, NM 87505 COVER PHOTO: Rio Ruidoso above Highway 70, September 2012. NMED/SWQB. Rio Ruidoso TMDL Final Draft TABLE OF CONTENTS TABLE OF CONTENTS ............................................................................................................................... i LIST OF TABLES ........................................................................................................................................ ii LIST OF FIGURES ...................................................................................................................................... ii LIST OF APPENDICES ............................................................................................................................... ii EXECUTIVE SUMMARY ......................................................................................................................... vi 1.0 INTRODUCTION .............................................................................................................. 2 2.0 SACRAMENTO MOUNTAIN CHARACTERISTICS ..................................................... 3 2.1 Location Description ..................................................................................................... 3 2.2 Geology and History ..................................................................................................... 6 2.3 Water Quality Standards and Designated Uses ............................................................ 7 2.4 Water Quality Sampling ............................................................................................... 9 2.4.1 Survey Design ...................................................................................................... 9 2.4.2 Hydrologic Conditions ....................................................................................... 11 3.0 PLANT NUTRIENTS AND TOTAL PHOSPHORUS .................................................... 13 3.1 Target Loading Capacity ............................................................................................. 13 3.2 Flow ............................................................................................................................ 17 3.3 TMDL Calculation ...................................................................................................... 19 3.4 Margin of Safety ......................................................................................................... 20 3.5 Load Allocations and Waste Load Allocations .......................................................... 20 3.5.1 Load Allocation ................................................................................................. 20 3.5.2 Waste Load Allocation ...................................................................................... 21 3.5.3 Load Reductions ................................................................................................ 23 3.5 Identification and Description of Pollutant Sources ................................................... 24 3.6 Linkage between Water Quality and Pollutant Sources ........................................................ 25 3.7 Consideration of Seasonal Variability ........................................................................ 29 3.8 Future Growth ............................................................................................................. 29 4.0 MONITORING PLAN ............................................................................................... 30 5.0 IMPLEMENTATION OF TMDLS ............................................................................ 32 5.1 Point Sources – NPDES permitting ..................................................................................... 32 5.2 Nonpoint Sources – WBP and BMP Coordination ............................................................... 33 5.3 Clean Water Act §319(h) Funding ...................................................................................... 34 5.4 Other Funding Opportunities and Restoration Efforts in the Rio Ruidoso Watershed ......... 35 6.0 APPLICABLE REGULATIONS and STAKEHOLDER ASSURANCES ............... 36 7.0 PUBLIC PARTICIPATION ....................................................................................... 38 8.0 REFERENCES ........................................................................................................... 39 APPENDIX A ............................................................................................................................................. 43 APPENDIX B ............................................................................................................................................. 46 APPENDIX C ............................................................................................................................................. 49 APPENDIX D ............................................................................................................................................. 55 APPENDIX E ............................................................................................................................................. 56 i Rio Ruidoso TMDL Final Draft LIST OF TABLES Table 2.1 SWQB 2012 Sacramento Mountains Sampling Stations ...................................... 10 Table 3.1 Applicable nutrient-related thresholds for the Rio Ruidoso watershed ................ 14 Table 3.2 2012-2014 Rio Ruidoso water quality data statistical summary .......................... 15 Table 3.3 2002 Algal Bioassay sites ..................................................................................... 16 Table 3.4 Active USGS gages in the Rio Ruidoso ............................................................... 18 Table 3.5 Flow summaries for Rio Ruidoso watershed ........................................................ 19 Table 3.6 Daily target loads for TP & TN ............................................................................ 19 Table 3.7 Watershed Load Allocation .................................................................................. 20 Table 3.8 Allocation of TMDLs for TP and TN ................................................................... 23 Table 3.9 Calculation of load reduction for TP and TN(a) .................................................... 23 Table 3.10 Pollutant source summary for plant nutrients and total phosphorus ..................... 24 LIST OF FIGURES Figure 2.1 Land Use and 2012 Sampling Stations in the Sacramento Mountains ......................... 4 Figure 2.2 Land Management and 2012 Sampling Stations in the Sacramento Moutain Watershed ............................................................................................................................... 5 Figure 2.3 Geologic Map of the Sacramento Mountains and 2012 Sampling Stations ................. 6 Figure 2.4 Daily mean discharge for the Rio Ruidoso near Hollywood, NM ............................. 11 Figure 2.5 Daily mean discharge for the Rio Ruidoso near Ruidoso, NM………………….….14 LIST OF APPENDICES Appendix A Conversion Factor Derivation Appendix B Probable Sources of Impairment Appendix C Water Quality and Flow Data Appendix D Algal Growth Potential Assay (AGP) Appendix E Response to Comments ii Rio Ruidoso TMDL Final Draft LIST OF ABBREVIATIONS 4Q3 4-Day, 3-year low-flow frequency AU Assessment Unit BLM Bureau of Land Management BMP Best management practices BST Bacterial Source Tracking CAFO Concentration Animal Feeding Operation CFR Code of Federal Regulations cfs Cubic feet per second cfu Coliform forming units CGP Construction general storm water permit CWA Clean Water Act oC Degrees Celsius DMR Discharge Monitoring Report DO Dissolved Oxygen EQIP Environmental Quality Incentive Program oF Degrees Fahrenheit HUC Hydrologic unit code j/m2/s Joules per square meter per second km2 Square kilometers LA Load allocation lbs/day Pounds per day MASS Monitoring, Assessment and Standards Section mgd Million gallons per day mg/L Milligrams per Liter mi2 Square miles mL Milliliters MOS Margin of safety MOU Memorandum of Understanding MS4 Municipal separate storm sewer system MSGP Multi-sector general storm water permit NM New Mexico NMAC New Mexico Administrative Code NMED New Mexico Environment Department NOI Notice of Intent NPDES National Pollutant Discharge Elimination System NPS Nonpoint source NRCS Natural Resource Conservation Service NTU Nephelometric Turbidity Units QAPP Quality Assurance Project Plan RFP Request for proposal SEE Standard Error of the Estimate SEV Severity of Ill Effect SWPPP Storm water pollution prevention plan SWQB Surface Water Quality Bureau iii Rio Ruidoso TMDL Final Draft TKN Total Kjeldahl Nitrogen TMDL Total Maximum Daily Load TN Total Nitrogen TP Total Phosphorous TSS Total Suspended Solids UL Upstream Loading USEPA U.S. Environmental Protection Agency USFS U.S. Forest Service USGS U.S. Geological Survey WLA Waste load allocation WBS Watershed-based plan WQCC Water Quality Control Commission WQS Water quality standards WQX Water quality exchange WWTP Wastewater