Total Maximum Daily Loads for the Mohican River Watershed Draft Report for Public Review Division of Surface Water December 2, 2014 Photo caption: Clear Fork of the Mohican River at Benedict Road bridge outside of the Village of Butler. Mohican River Watershed TMDLs Table of Contents 1 Introduction ........................................................................................................................ 14 1.1 The Clean Water Act Requirement to Address Impaired Waters ..................................... 14 1.2 Public Involvement ........................................................................................................... 19 1.3 Organization of Report ..................................................................................................... 20 2 Characteristics and Expectations of the Watershed ............................................................... 21 2.1 Watershed Characteristics ................................................................................................ 21 2.1.1 Population and Distribution ................................................................................. 21 2.1.2 Land Use............................................................................................................... 22 2.1.3 Point Source Discharges ...................................................................................... 22 2.1.4 Public Drinking Water Supplies ............................................................................ 23 2.2 Water Quality Standards................................................................................................... 23 2.2.1 Aquatic Life Use ................................................................................................... 24 2.2.2 Recreation Use ..................................................................................................... 25 2.2.3 Public Drinking Water Supply Use ....................................................................... 27 2.2.4 Human Health (Fish Contaminants) Use .............................................................. 29 3 Water Quality Conditions in the Watershed .......................................................................... 30 3.1 Headwaters Black Fork Mohican River (05040002 01) ..................................................... 31 3.2 Rocky Fork – Black Fork Mohican River (05040002 02) .................................................... 36 3.3 Headwaters Clear Fork Mohican River (05040002 03) ..................................................... 39 3.4 Possum Run – Clear Fork Mohican River .......................................................................... 43 3.5 Muddy Fork Mohican River (05040002 05) ...................................................................... 46 3.6 Jerome Fork – Mohican River (05040002 06) ................................................................... 49 3.7 Lake Fork Mohican River (05040002 07) .......................................................................... 52 3.8 Mohican River (05040002 08) ........................................................................................... 56 3.9 Mohican River Mainstem (Large River Assessment Unit) ................................................. 60 4 Methods to Calculate Load Reductions ................................................................................. 62 4.1 Load Duration Curves........................................................................................................ 72 4.1.1 Justification .......................................................................................................... 72 4.1.2 Sources of Data .................................................................................................... 73 4.1.3 Target(s) ............................................................................................................... 73 4.1.4 Allowance for Future Growth .............................................................................. 73 4.1.5 Seasonality and Critical Conditions ...................................................................... 74 4.2 Habitat and Sediment Method (QHEI) .............................................................................. 75 4.2.1 Justification .......................................................................................................... 75 4.2.2 Sources of Data .................................................................................................... 76 4.2.3 Target(s) ............................................................................................................... 76 4.2.4 Allowance for Future Growth .............................................................................. 78 4.2.5 Seasonality and Critical Conditions ...................................................................... 78 4.3 Margin of Safety ................................................................................................................ 78 5 Load Reduction Results ........................................................................................................ 80 5.1 Marsh Run (05040002 01 01) ........................................................................................... 80 5.2 Headwaters Black Fork Mohican River (05040002 01 02) ................................................ 81 5.3 Brubaker Creek (05040002 01 03) .................................................................................... 82 5.4 Whetstone Creek (05040002 01 04) ................................................................................. 83 i Mohican River Watershed TMDLs 5.5 Shipp Creek-Black Fork Mohican River (05040002 01 05) ................................................ 83 5.6 Village of Pavonia-Black Fork Mohican River (05040002 02 01) ...................................... 85 5.7 Headwaters Rocky Fork (05040002 02 03) ....................................................................... 88 5.8 Outlet Rocky Fork (05040002 02 04) ................................................................................ 89 5.9 Charles Mill-Black Fork Mohican River (05040002 02 05) ................................................ 90 5.10 Cedar Fork (05040002 03 02) ........................................................................................... 93 5.11 Town of Lexington-Clear Fork Mohican River (05040002 03 03) ..................................... 94 5.12 Honey Creek-Clear Fork Mohican River (05040002 04 01) .............................................. 95 5.13 Opossum Run (05040002 04 02) ...................................................................................... 96 5.14 Slater Run-Clear Fork Mohican River (05040002 04 03)................................................... 97 5.15 Pine Run (05040002 04 04) ............................................................................................... 98 5.16 Switzer Creek-Clear Fork Mohican River (05040002 04 05) ............................................. 98 5.17 Upper Muddy Fork Mohican River (05040002 05 01) ...................................................... 99 5.18 Middle Muddy Fork Mohican River (05040002 05 02) ................................................... 100 5.19 Lower Muddy Fork Mohican River (05040002 05 03) .................................................... 101 5.20 Lang Creek (05040002 06 01) ......................................................................................... 102 5.21 Orange Creek (05040002 06 02) ..................................................................................... 102 5.22 Katotawa Creek (05040002 06 03) ................................................................................. 103 5.23 Oldtown Run (05040002 06 04) ...................................................................................... 103 5.24 Jerome Fork-Mohican River (05040002 06 05) .............................................................. 104 5.25 Glenn Run-Jerome Fork Mohican River (05040002 06 06) ............................................. 106 5.26 Crab Run (05040002 07 01) ............................................................................................ 107 5.27 Mohicanville Dam-Lake Fork Mohican River (05040002 07 02) ..................................... 108 5.28 Plum Run-Lake Fork Mohican River (05040002 07 03) ................................................... 111 5.29 Honey Creek (05040002 08 01) ...................................................................................... 111 5.30 Town of Perrysville-Black Fork Mohican River (05040002 08 02) .................................. 112 5.31 Big Run-Black Fork Mohican River (05040002 08 03) ..................................................... 113 5.32 Negro Run-Mohican River (05040002 08 05) ................................................................. 114 5.33 Mohican River Mainstem (05040002 90 01) .................................................................. 114 5.34 Summary of Nutrient Wasteload Allocations ................................................................. 118 5.35 Sediment and Habitat TMDL Results .............................................................................. 122 6 Water Quality Improvement Strategy ................................................................................. 124 6.1 Regulatory Recommendations........................................................................................ 131 6.2 Headwaters Black Fork Mohican River (05040002 01) ..................................................