Nutrient Management Definitions and Recommended Nutrient Reduction Efficiencies of Nutrient Management For Use in Phase 6.0 of the Chesapeake Bay Program Watershed Model Recommendations for Approval by the Water Quality Goal Implementation Team’s Watershed Technical and Agricultural Workgroups Submitted by the Phase 6.0 Nutrient Management BMP Expert Panel Submitted to: Agriculture Workgroup Chesapeake Bay Program August 1, 2016 Contents ACRONYMS ......................................................................................................................................................................................... 4 SUMMARY OF RECOMMENDATIONS .................................................................................................................................................. 6 1 INTRODUCTION .......................................................................................................................................................................... 6 2 PRACTICE DEFINITIONS ............................................................................................................................................................... 6 Practice Name(s) .................................................................................................................................................................................. 7 2.1 NM CORE AND SUPPLEMENTAL ELEMENT DETAILED DEFINITIONS ........................................................................................................... 13 2.2 NITROGEN CORE NM BMP ELEMENTS .............................................................................................................................................. 13 2.3 PHOSPHORUS CORE NM BMP ELEMENTS .......................................................................................................................................... 15 2.4 NITROGEN NM SUPPLEMENTAL BMPS .............................................................................................................................................. 16 2.5 PHOSPHOROUS NM SUPPLEMENTAL BMPS ....................................................................................................................................... 17 3 EFFECTIVENESS ESTIMATES .......................................................................................................................................................18 3.1 SUMMARY OF EFFECTIVENESS ESTIMATES ........................................................................................................................................... 18 3.1.1. N Core NM BMPs .............................................................................................................................................................. 18 3.1.2. P Core NM BMPs .............................................................................................................................................................. 18 3.1.3. N Nutrient Management Supplemental BMPs ................................................................................................................. 19 3.1.4. P Nutrient Management Supplemental BMPs ................................................................................................................. 20 3.2 JUSTIFICATION FOR EFFECTIVENESS ESTIMATES .................................................................................................................................... 20 3.3 METHOD FOR APPLYING CORE AND SUPPLEMENTAL BMP EFFICIENCIES ................................................................................................... 20 4 REVIEW OF LITERATURE AND DATA GAPS .................................................................................................................................24 4.1 THE AVAILABLE SCIENCE FOR N BMPS ............................................................................................................................................... 24 4.2 THE AVAILABLE SCIENCE FOR P BMPS ............................................................................................................................................... 25 5 APPLICATION OF PRACTICE ESTIMATES .....................................................................................................................................25 5.1 LOAD SOURCES .............................................................................................................................................................................. 25 5.2 PRACTICE BASELINE ........................................................................................................................................................................ 26 5.3 HYDROLOGIC CONDITIONS ............................................................................................................................................................... 27 5.4 SEDIMENT .................................................................................................................................................................................... 27 5.5 SPECIES OF NITROGEN AND PHOSPHORUS ........................................................................................................................................... 27 5.6 GEOGRAPHIC CONSIDERATIONS ........................................................................................................................................................ 27 5.7 TEMPORAL CONSIDERATIONS ........................................................................................................................................................... 27 5.8 PRACTICE LIMITATIONS ................................................................................................................................................................... 27 5.9 POTENTIAL INTERACTIONS WITH OTHER PRACTICES ............................................................................................................................... 27 6 PRACTICE MONITORING AND REPORTING .................................................................................................................................28 6.1 PHASE 6.0 NUTRIENT MANAGEMENT TRACKING, VERIFICATION, AND REPORTING ..................................................................................... 28 6.2 FUTURE VERIFICATION OF NUTRIENT MANAGEMENT PRACTICES ............................................................................................................. 29 7 REFERENCES ..............................................................................................................................................................................29 APPENDIX A: TECHNICAL REQUIREMENTS FOR REPORTING AND SIMULATING NUTRIENT MANAGEMENT BMPS IN THE PHASE 6 WATERSHED MODEL ..........................................................................................................................................................................39 APPENDIX B: METHODS TO ESTIMATE HISTORIC IMPLEMENTATION .................................................................................................45 APPENDIX C: NUTRIENT MANAGEMENT PHASE 6.0 EXPERT PANEL CHARGE DOCUMENT ..................................................................50 APPENDIX D: APPROVED NUTRIENT MANAGEMENT EXPERT PANEL MEETING MINUTES ..................................................................57 APPENDIX E: CONSOLIDATED RESPONSE TO COMMENTS ON: DEFINITIONS AND RECOMMENDED NUTRIENT REDUCTION EFFICIENCIES OF NUTRIENT MANAGEMENT FOR USE IN PHASE 6.0 OF THE CHESAPEAKE BAY PROGRAM WATERSHED MODEL (2016) 2 ..........................................................................................................................................................................................................57 APPENDIX F: CONFORMITY WITH WQGIT BMP PROTOCOL ................................................................................................................58 Figure 1. Linkage of Core and Supplemental N Nutrient Management Practices ................................................................................12 Figure 2. Linkage of Core and Supplemental P Nutrient Management Practices ................................................................................13 Figure 3. Assignment of N Nutrient Management Credits. Variables A and B refer to the land use specific N Core Non-Nutrient Management BMP efficiency and the N Core Nutrient Management BMP efficiency, respectively, as presented in Table 12. Variables C, D and E refer to the land use specific N Rate Supplemental BMP efficiency, the N Placement Supplemental BMP efficiency and the N Timing Supplemental BMP efficiency, respectively, as presented in Table 14. ...................................................23 Figure 4. Assignment of P Nutrient Management Credits. Variables F and G refer to the land use specific P Core Non-Nutrient Management BMP efficiency and the P Core Nutrient Management BMP efficiency, respectively, as presented in Table 13. Variables H, I and J refer to the land use specific P Rate Supplemental BMP efficiency, the P Placement Supplemental BMP efficiency and the P Timing Supplemental BMP efficiency, respectively, as presented in Table 15. ...................................................24 Table 1. CBP Phase 6.0 Nutrient Management Expert Panel Membership .......................................................................................... 6 Table 2. Elements of