J_2024 05 09_West Orange Stormwater Management Plan

APPENDIX A - DESIGN NOTES

Client Project # Project Name PSE&G Date 03/29/23 West Orange Switching Station Known Data and Notes 144507 Known Data: Page 1 Made By Checked By Preliminary of 19 SJM MJB X Final References Hydrologic Soil Type (HSG): USDA NRCS Web Soil Survey URBONB: Urban Land, Boonton substratum, 0 to 8 percent slopes Hydrologic Soil Group: D (no HSG listed, assume D) USBONB: Urban Land, Boonton substratum - Boonton complex, 0 to 8 percent slopes Hydrologic Soil Group: B (used HSG D for a conservative evaluation) Water Quality Design Storm is 1.25 inches of rainfall in two hours. 24-Hour Precipitation Depths: 2 Year = 10 Year = 25 Year = 100 Year = 3.42 5.21 6.44 8.71 in in in in NOAA National Weather Service Precipitation Frequency Data Server Essex County NOAA 24-hr Type D Storm Distribution Current Precipitation Adjustment Factors 2 Year = 1.01 x 3.42 = 3.45 in 5.37 in 10 Year = 1.03 x 5.21 = 100 Year = 1.06 x 8.71 = 9.23 in Future Precipitation Change Factors 1.19 x 3.42 = 4.07 2 Year = 1.22 x 5.21 = 6.36 10 Year = 100 Year = 1.33 x 8.71 = 11.58 in in in Notes: 1. Description: Impervious, Pavement >75% Grass cover, Good Yard Stone/Gravel Pad Brush, Good Non-Contributory Curve Numbers (CN): # # # # N/A HSG Rating: D D D D D 2. HydroCAD software using Calculate separate Pervious/Impervious runoff for all Curve Number (CN) calculations 3. The station crushed stone curve number was established using the equation found in the NJDEP BMP Manual, Chapter 5, where CN = 1000/(S+10), where S is equal to the storage depth in the crushed stone (in this case, 4”), with a voids ratio of 40%. https://burnsmcd.sharepoint.com/sites/PSEGSub/Shared Documents/WestOrange26kVLifecyclePrelim_144507/Dsgn/Sub/Civil/Storm_Wtr/6. 5/10/2024 4:13 PM Storm Water Management Report/Appendix A - Design Notes/Archived/West Orange Design Notes_Blake.xlsx

PSE&G Client Project # Project Name Date 03/29/23 West Orange Switching Station PO-DA 1 144507 2 Page Made By Checked By Preliminary Land Use Impervious, Pavement >75% Grass cover, Good Yard Stone/Gravel Pad Brush, Good Non-Contributory 7,888 19,498 2,304 23,117 0 sf sf sf sf sf 0.181 0.448 0.053 0.531 0.000 ac ac ac ac ac D D D D D CN = CN = CN = CN = CN = 98 80 85 73 0 Total Area (TA)= TA (less non contributory)= 52,807 sf 52,807 sf 1.21 1.21 ac ac Composite CN = 80 19 of SJM MJB Final X References Time of Concentration: Sheet Flow 23 L= ft 3.52% % S= n= 0.011 Smooth surfaces Shallow Concentrated Flow L= S= 31 ft 24.37% % Woodland Shallow Concentrated Flow L= 287 ft S= 4.62% % Tc = 3.65 Flows: Current: Q(2) = Q(10) = Q(100) = Short Grass Pasture min Future: Q(2) = Q(10) = Q(100) = 3.19 6.07 12.86 cfs cfs cfs HydroCAD HydroCAD HydroCAD Runoff Volume (Weighted Average Volume): Current: Future: V(2) = V(2) = 0.167 ac-ft V(10) = V(10) = 0.327 ac-ft V(100) = V(100) = 0.682 ac-ft 0.217 0.416 0.908 ac-ft ac-ft ac-ft HydroCAD HydroCAD HydroCAD 2.45 4.81 9.80 cfs cfs cfs https://burnsmcd.sharepoint.com/sites/PSEGSub/Shared Documents/WestOrange26kVLifecyclePrelim_144507/Dsgn/Sub/Civil/Storm_Wtr/6. 5/10/2024 4:13 PM Storm Water Management Report/Appendix A - Design Notes/Archived/West Orange Design Notes_Blake.xlsx

PSE&G Client Project # Project Name Date 03/29/23 West Orange Switching Station PO-DA 6 144507 3 Page Made By Checked By Preliminary Land Use Impervious, Pavement >75% Grass cover, Good Yard Stone/Gravel Pad Brush, Good Non-Contributory 18,485 9,771 53,605 14,992 30,878 sf sf sf sf sf 0.424 0.224 1.231 0.344 0.709 ac ac ac ac ac D D D D D CN = CN = CN = CN = CN = 98 80 85 73 0 Total Area (TA)= TA (less non contributory)= 127,731 sf 96,853 sf 2.93 2.22 ac ac Composite CN = 85 19 of SJM MJB Final X References Time of Concentration: Sheet Flow 100 ft L= 5.43% % S= n= 0.400 Woods: Light underbrush Shallow Concentrated Flow L= S= 67 ft 9.08% % Short Grass Pasture Shallow Concentrated Flow L= 43 ft S= 28.13% % Short Grass Pasture Shallow Concentrated Flow L= 281 ft S= 0.69% % Unpaved Tc = 16.99 Flows: Current: Q(2) = Q(10) = Q(100) = min Future: Q(2) = Q(10) = Q(100) = 4.50 8.07 16.29 cfs cfs cfs HydroCAD HydroCAD HydroCAD Runoff Volume (Weighted Average Volume): Current: Future: 0.377 ac-ft V(2) = V(2) = V(10) = 0.693 ac-ft V(10) = V(100) = 1.369 ac-ft V(100) = 0.477 0.863 1.791 ac-ft ac-ft ac-ft HydroCAD HydroCAD HydroCAD 3.45 6.35 12.28 cfs cfs cfs https://burnsmcd.sharepoint.com/sites/PSEGSub/Shared Documents/WestOrange26kVLifecyclePrelim_144507/Dsgn/Sub/Civil/Storm_Wtr/6. 5/10/2024 4:13 PM Storm Water Management Report/Appendix A - Design Notes/Archived/West Orange Design Notes_Blake.xlsx

Client Project # Project Name PSE&G Date 03/29/23 West Orange Switching Station PO-DA 7 144507 Page 4 Made By Checked By Preliminary Land Use Impervious, Pavement >75% Grass cover, Good Yard Stone/Gravel Pad Brush, Good Non-Contributory 4,346 29,340 22,892 16,829 28,075 sf sf sf sf sf 0.100 0.674 0.526 0.386 0.645 ac ac ac ac ac D D D D D CN = CN = CN = CN = CN = 98 80 85 73 0 Total Area (TA)= TA (less non contributory)= 101,482 sf 73,407 sf 2.33 1.69 ac ac Composite CN = 81 of 19 SJM MJB Final X References Time of Concentration: Sheet Flow 49 L= ft 7.91% % S= n= 0.400 Woods: Light underbrush Shallow Concentrated Flow L= S= 151 ft 0.71% % Unpaved Shallow Concentrated Flow L= 239 ft 2.60% % S= Tc = 11.59 Flows: Current: Q(2) = Q(10) = Q(100) = Short Grass Pasture min Future: Q(2) = Q(10) = Q(100) = 3.49 6.61 13.89 cfs cfs cfs HydroCAD HydroCAD HydroCAD Runoff Volume (Weighted Average Volume): Current: Future: 0.239 ac-ft V(2) = V(2) = V(10) = V(10) = 0.467 ac-ft V(100) = 0.968 ac-ft V(100) = 0.310 0.592 1.284 ac-ft ac-ft ac-ft HydroCAD HydroCAD HydroCAD 2.66 5.20 10.52 cfs cfs cfs https://burnsmcd.sharepoint.com/sites/PSEGSub/Shared Documents/WestOrange26kVLifecyclePrelim_144507/Dsgn/Sub/Civil/Storm_Wtr/6. 5/10/2024 4:13 PM Storm Water Management Report/Appendix A - Design Notes/Archived/West Orange Design Notes_Blake.xlsx

Client Project # Project Name PSE&G Date 03/29/23 West Orange Switching Station PO-DA 8 144507 Page 5 Made By Checked By Preliminary Land Use Impervious, Pavement >75% Grass cover, Good Yard Stone/Gravel Pad Brush, Good Non-Contributory 11,671 0 5,115 0 2,493 sf sf sf sf sf 0.268 0.000 0.117 0.000 0.057 ac ac ac ac ac D D D D D CN = CN = CN = CN = CN = 98 80 85 73 0 Total Area (TA)= TA (less non contributory)= 19,279 sf 16,786 sf 0.44 0.39 ac ac Composite CN = 94 of 19 SJM MJB Final X References Time of Concentration: Gravel Sheet Flow 100 ft L= 1.60% % S= n= 0.100 Gravel Sheet Flow Shallow Concentrated Flow L= S= 78 ft 1.65% % Tc = 7.50 Flows: Current: Q(2) = Q(10) = Q(100) = Unpaved min Future: Q(2) = Q(10) = Q(100) = 1.32 2.14 4.01 cfs cfs cfs HydroCAD HydroCAD HydroCAD Runoff Volume (Weighted Average Volume): Current: Future: 0.091 ac-ft V(2) = V(2) = V(10) = V(10) = 0.151 ac-ft V(100) = 0.273 ac-ft V(100) = 0.110 0.182 0.348 ac-ft ac-ft ac-ft HydroCAD HydroCAD HydroCAD 1.07 1.74 3.09 cfs cfs cfs https://burnsmcd.sharepoint.com/sites/PSEGSub/Shared Documents/WestOrange26kVLifecyclePrelim_144507/Dsgn/Sub/Civil/Storm_Wtr/6. 5/10/2024 4:13 PM Storm Water Management Report/Appendix A - Design Notes/Archived/West Orange Design Notes_Blake.xlsx

Client Project # Project Name PSE&G Date 03/29/23 West Orange Switching Station PO-DA A 144507 Page 6 Made By Checked By Preliminary Land Use Impervious, Pavement >75% Grass cover, Good Yard Stone/Gravel Pad Brush, Good Non-Contributory 9,878 14,245 39,395 14,769 2,061 sf sf sf sf sf 0.227 0.327 0.904 0.339 0.047 ac ac ac ac ac D D D D D CN = CN = CN = CN = CN = 98 80 85 73 0 Total Area (TA)= TA (less non contributory)= 80,348 sf 78,287 sf 1.84 1.80 ac ac Composite CN = 83 of 19 SJM MJB Final X References Time of Concentration: Sheet Flow L= 100 ft 5.43% % S= n= 0.400 Woods: Light underbrush Shallow Concentrated Flow L= S= 67 ft 5.40% % Short Grass Pasture Gravel Shallow Concentrated Flow L= 43 ft S= 28.10% % Short Grass Pasture Gravel Shallow Concentrated Flow L= 281 ft S= 0.69% % Unpaved Tc = 17.15 Flows: WQ = Q(25) = Current: Q(2) = Q(10) = Q(100) = min 1.06 6.26 2.63 4.94 9.73 cfs cfs cfs cfs HydroCAD Future: Q(2) = Q(10) = Q(100) = Runoff Volume (Weighted Average Volume): WQ = 0.049 ac-ft V(25) = 0.682 ac-ft Current: Future: V(2) = 0.284 ac-ft V(2) = V(10) = 0.535 ac-ft V(10) = V(100) = 1.076 ac-ft V(100) = 3.45 6.33 12.98 cfs cfs cfs HydroCAD HydroCAD HydroCAD HydroCAD HydroCAD 0.363 0.671 1.415 ac-ft ac-ft ac-ft HydroCAD HydroCAD HydroCAD https://burnsmcd.sharepoint.com/sites/PSEGSub/Shared Documents/WestOrange26kVLifecyclePrelim_144507/Dsgn/Sub/Civil/Storm_Wtr/6. 5/10/2024 4:13 PM Storm Water Management Report/Appendix A - Design Notes/Archived/West Orange Design Notes_Blake.xlsx

Client Project # Project Name PSE&G Date 03/29/23 West Orange Switching Station PO-DA B 144507 Page 7 Made By Checked By Preliminary Land Use Impervious, Pavement >75% Grass cover, Good Yard Stone/Gravel Pad Brush, Good Non-Contributory 0 1,874 599 26,074 0 sf sf sf sf sf 0.000 0.043 0.014 0.599 0.000 ac ac ac ac ac D D D D D CN = CN = CN = CN = CN = 98 80 85 73 0 Total Area (TA)= TA (less non contributory)= 28,547 sf 28,547 sf 0.66 0.66 ac ac Composite CN = 74 of 19 SJM MJB Final X References Time of Concentration: Sheet Flow L= 100 ft 9.00% % S= n= 0.400 Woods: Light underbrush Shallow Concentrated Flow L= S= 64 ft 19.20% % Short Grass Pasture North Channel L= 134 ft S= 0.94% % Tc = 12.41 Flows: WQ = Q(25) = Current: Q(2) = Q(10) = Q(100) = Earth, long dense weeds min 0.08 2.09 0.68 1.56 3.52 cfs cfs cfs cfs HydroCAD Future: Q(2) = Q(10) = Q(100) = Runoff Volume (Weighted Average Volume): WQ = 0.004 ac-ft V(25) = 0.192 ac-ft Current: Future: V(2) = 0.065 ac-ft V(2) = V(10) = 0.144 ac-ft V(10) = V(100) = 0.327 ac-ft V(100) = 0.98 2.11 4.89 cfs cfs cfs HydroCAD HydroCAD HydroCAD HydroCAD HydroCAD 0.089 0.189 0.446 ac-ft ac-ft ac-ft HydroCAD HydroCAD HydroCAD https://burnsmcd.sharepoint.com/sites/PSEGSub/Shared Documents/WestOrange26kVLifecyclePrelim_144507/Dsgn/Sub/Civil/Storm_Wtr/6. 5/10/2024 4:13 PM Storm Water Management Report/Appendix A - Design Notes/Archived/West Orange Design Notes_Blake.xlsx

Client Project # Project Name PSE&G Date 03/29/23 West Orange Switching Station PO-DA C 144507 Page 8 Made By Checked By Preliminary Land Use Impervious, Pavement >75% Grass cover, Good Yard Stone/Gravel Pad Brush, Good Non-Contributory 4,299 2,396 17,985 0 0 sf sf sf sf sf 0.099 0.055 0.413 0.000 0.000 ac ac ac ac ac D D D D D CN = CN = CN = CN = CN = 98 80 85 73 0 Total Area (TA)= TA (less non contributory)= 24,680 sf 24,680 sf 0.57 0.57 ac ac Composite CN = 87 of 19 SJM MJB Final X References Time of Concentration: Gravel Sheet Flow L= 100 ft 0.18% % S= n= 0.100 Gravel Sheet Flow Shallow Concentrated Flow L= S= 64 ft 1.06% % Tc = 17.10 Flows: WQ = Q(25) = Current: Q(2) = Q(10) = Q(100) = Unpaved min 0.44 2.09 0.93 1.67 3.18 cfs cfs cfs cfs HydroCAD Future: Q(2) = Q(10) = Q(100) = Runoff Volume (Weighted Average Volume): WQ = 0.020 ac-ft V(25) = 0.232 ac-ft Current: Future: V(2) = 0.101 ac-ft V(2) = V(10) = 0.184 ac-ft V(10) = V(100) = 0.359 ac-ft V(100) = 1.21 2.13 4.23 cfs cfs cfs HydroCAD HydroCAD HydroCAD HydroCAD HydroCAD 0.128 0.228 0.467 ac-ft ac-ft ac-ft HydroCAD HydroCAD HydroCAD https://burnsmcd.sharepoint.com/sites/PSEGSub/Shared Documents/WestOrange26kVLifecyclePrelim_144507/Dsgn/Sub/Civil/Storm_Wtr/6. 5/10/2024 4:13 PM Storm Water Management Report/Appendix A - Design Notes/Archived/West Orange Design Notes_Blake.xlsx

Client Project # Project Name PSE&G Date 03/29/23 West Orange Switching Station PO-DA D 144507 Page 9 Made By Checked By Preliminary Land Use Impervious, Pavement >75% Grass cover, Good Yard Stone/Gravel Pad Brush, Good Non-Contributory 0 3,662 0 2,759 0 sf sf sf sf sf 0.000 0.084 0.000 0.063 0.000 ac ac ac ac ac D D D D D CN = CN = CN = CN = CN = 98 80 85 73 0 Total Area (TA)= TA (less non contributory)= 6,421 6,421 sf sf 0.15 0.15 ac ac Composite CN = 77 of 19 SJM MJB Final X References Time of Concentration: Sheet Flow 85 L= ft 17.73% % S= n= 0.400 Tc = 6.98 Flows: WQ = Q(25) = Current: Q(2) = Q(10) = Q(100) = Woods: Light underbrush min 0.04 0.62 0.23 0.48 1.01 cfs cfs cfs cfs HydroCAD Future: Q(2) = Q(10) = Q(100) = Runoff Volume (Weighted Average Volume): WQ = 0.002 ac-ft V(25) = 0.047 ac-ft Current: Future: V(2) = 0.017 ac-ft V(2) = V(10) = 0.036 ac-ft V(10) = V(100) = 0.078 ac-ft V(100) = 0.31 0.63 1.38 cfs cfs cfs HydroCAD HydroCAD HydroCAD HydroCAD HydroCAD 0.023 0.046 0.106 ac-ft ac-ft ac-ft HydroCAD HydroCAD HydroCAD https://burnsmcd.sharepoint.com/sites/PSEGSub/Shared Documents/WestOrange26kVLifecyclePrelim_144507/Dsgn/Sub/Civil/Storm_Wtr/6. 5/10/2024 4:13 PM Storm Water Management Report/Appendix A - Design Notes/Archived/West Orange Design Notes_Blake.xlsx