J_2024 05 09_West Orange Stormwater Management Plan

Post-Developed (O-1B) NJ DEP 2-hr WQ Rainfall=1.25", P2=3.42" West Orange HydroCAD_Post Printed 5/13/2024 Page 32 Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Primary OutFlow Max=0.08 cfs @ 1.54 hrs HW=595.04' TW=585.17' (Dynamic Tailwater) 1=SD-24 Outlet (Elevation F) (Passes 0.08 cfs of 16.59 cfs potential flow) 2=Water Quatity (Elevation G) (Orifice Controls 0.08 cfs @ 2.35 fps) 3=Water Quantity (Elevation H) ( Controls 0.00 cfs) 4=Overflow Grate (Elevation I) ( Controls 0.00 cfs) Pond 6P: BR-04 Hydrograph 0.55 Inflow Primary 0.50 cfs Inflow Area=0.317 ac Peak Elev=595.04' Storage=410 cf 0.5 0.45 0.4 Flow (cfs) 0.35 0.3 0.25 0.2 0.15 0.1 0.08 cfs 0.05 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Time (hours) 15 16 17 18 19 20 21 22 23 24

Post-Developed (O-1B) NJ DEP 2-hr WQ Rainfall=1.25", P2=3.42" West Orange HydroCAD_Post Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Hydrograph for Pond 6P: BR-04 Time (hours) 0.00 0.50 1.00 1.50 2.00 2.50 3.00 3.50 4.00 4.50 5.00 5.50 6.00 6.50 7.00 7.50 8.00 8.50 9.00 9.50 10.00 10.50 11.00 11.50 12.00 12.50 13.00 13.50 14.00 14.50 15.00 15.50 16.00 16.50 17.00 17.50 18.00 18.50 19.00 19.50 20.00 20.50 21.00 21.50 22.00 22.50 23.00 23.50 24.00 Inflow (cfs) 0.00 0.01 0.27 0.08 0.02 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Storage Elevation (cubic-feet) (feet) 0 594.70 2 594.70 96 594.78 410 595.04 365 595.00 256 594.91 176 594.85 129 594.81 100 594.78 81 594.77 68 594.76 58 594.75 51 594.74 45 594.74 40 594.73 36 594.73 33 594.73 31 594.73 28 594.72 26 594.72 25 594.72 23 594.72 22 594.72 20 594.72 19 594.72 18 594.72 18 594.72 17 594.71 16 594.71 15 594.71 15 594.71 14 594.71 14 594.71 13 594.71 13 594.71 12 594.71 12 594.71 12 594.71 11 594.71 11 594.71 11 594.71 10 594.71 10 594.71 10 594.71 9 594.71 9 594.71 9 594.71 9 594.71 9 594.71 Primary (cfs) 0.00 0.00 0.01 0.08 0.07 0.05 0.03 0.02 0.01 0.01 0.01 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Printed 5/13/2024 Page 33

Post-Developed (O-1B) NJ DEP 2-hr WQ Rainfall=1.25", P2=3.42" West Orange HydroCAD_Post Printed 5/13/2024 Page 34 Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Summary for Pond 8P: O-1B Inflow Area = Inflow = Primary = 1.863 ac, 27.41% Impervious, Inflow Depth > 0.48" for WQ event 0.48 cfs @ 1.68 hrs, Volume= 0.074 af 0.48 cfs @ 1.68 hrs, Volume= 0.074 af, Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.0100 hrs Pond 8P: O-1B Hydrograph Inflow Primary 0.48 cfs Inflow Area=1.863 ac 0.48 cfs 0.5 0.45 0.4 Flow (cfs) 0.35 0.3 0.25 0.2 0.15 0.1 0.05 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Time (hours) 15 16 17 18 19 20 21 22 23 24

Post-Developed (O-1B) West Orange HydroCAD_Post NJ DEP 2-hr WQ Rainfall=1.25", P2=3.42" Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Hydrograph for Pond 8P: O-1B Time (hours) 0.00 0.50 1.00 1.50 2.00 2.50 3.00 3.50 4.00 4.50 5.00 5.50 6.00 6.50 7.00 7.50 8.00 8.50 9.00 9.50 10.00 10.50 11.00 11.50 12.00 12.50 13.00 13.50 14.00 14.50 15.00 15.50 16.00 16.50 17.00 17.50 18.00 18.50 19.00 19.50 20.00 20.50 21.00 21.50 22.00 22.50 23.00 23.50 24.00 Inflow Elevation (cfs) (feet) 0.00 0.00 0.03 0.47 0.45 0.33 0.19 0.10 0.05 0.03 0.02 0.01 0.01 0.01 0.01 0.01 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Primary (cfs) 0.00 0.00 0.03 0.47 0.45 0.33 0.19 0.10 0.05 0.03 0.02 0.01 0.01 0.01 0.01 0.01 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Printed 5/13/2024 Page 35

Post-Developed (O-1B) West Orange HydroCAD_Post NJ DEP 2-hr WQ Rainfall=1.25", P2=3.42" Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Printed 5/13/2024 Page 36 Summary for Pond 13P: SD-25, SD-26 Inflow Area = 1.863 ac, 27.41% Impervious, Inflow Depth > 0.48" for WQ event Inflow = 0.48 cfs @ 1.68 hrs, Volume= 0.074 af Outflow = 0.48 cfs @ 1.68 hrs, Volume= 0.074 af, Atten= 0%, Lag= 0.0 min Primary = 0.48 cfs @ 1.68 hrs, Volume= 0.074 af Routed to Pond 8P : O-1B Routing by Dyn-Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.0100 hrs Peak Elev= 580.74' @ 1.68 hrs Surf.Area= 0.000 ac Storage= 0.000 af Plug-Flow detention time= 0.1 min calculated for 0.074 af (100% of inflow) Center-of-Mass det. time= 0.0 min ( 154.8 - 154.8 ) Volume #1 Device #1 Invert 580.69' Routing Primary Avail.Storage 0.007 af Invert 580.44' Storage Description 15.0" Round SD-25 L= 262.4' S= 0.0150 '/' Outlet Devices 18.0" Round SD-26 L= 29.4' RCP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 580.44' / 580.15' S= 0.0099 '/' Cc= 0.900 n= 0.011 Concrete pipe, straight & clean, Flow Area= 1.77 sf Primary OutFlow Max=0.48 cfs @ 1.68 hrs HW=580.74' TW=0.00' (Dynamic Tailwater) 1=SD-26 (Inlet Controls 0.48 cfs @ 1.88 fps)

Post-Developed (O-1B) NJ DEP 2-hr WQ Rainfall=1.25", P2=3.42" West Orange HydroCAD_Post Printed 5/13/2024 Page 37 Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Pond 13P: SD-25, SD-26 Hydrograph Inflow Primary 0.48 cfs Inflow Area=1.863 ac Peak Elev=580.74' Storage=0.000 af 18.0" Round Culvert n=0.011 L=29.4' S=0.0099 '/' 0.48 cfs 0.5 0.45 0.4 Flow (cfs) 0.35 0.3 0.25 0.2 0.15 0.1 0.05 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Time (hours) 15 16 17 18 19 20 21 22 23 24

Post-Developed (O-1B) NJ DEP 2-hr WQ Rainfall=1.25", P2=3.42" West Orange HydroCAD_Post Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Hydrograph for Pond 13P: SD-25, SD-26 Time (hours) 0.00 0.50 1.00 1.50 2.00 2.50 3.00 3.50 4.00 4.50 5.00 5.50 6.00 6.50 7.00 7.50 8.00 8.50 9.00 9.50 10.00 10.50 11.00 11.50 12.00 12.50 13.00 13.50 14.00 14.50 15.00 15.50 16.00 16.50 17.00 17.50 18.00 18.50 19.00 19.50 20.00 20.50 21.00 21.50 22.00 22.50 23.00 23.50 24.00 Inflow (cfs) 0.00 0.00 0.03 0.47 0.45 0.33 0.19 0.10 0.05 0.03 0.02 0.01 0.01 0.01 0.01 0.01 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Storage Elevation (acre-feet) (feet) 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.74 0.000 580.74 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 Primary (cfs) 0.00 0.00 0.03 0.47 0.45 0.33 0.19 0.10 0.05 0.03 0.02 0.01 0.01 0.01 0.01 0.01 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Printed 5/13/2024 Page 38

Post-Developed (O-1B) NJ DEP 2-hr WQ Rainfall=1.25", P2=3.42" West Orange HydroCAD_Post Printed 5/13/2024 Page 39 Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Summary for Pond 14P: SD-24 Inflow Area = 1.622 ac, 27.37% Impervious, Inflow Depth > 0.48" for WQ event Inflow = 0.41 cfs @ 1.74 hrs, Volume= 0.065 af Outflow = 0.41 cfs @ 1.74 hrs, Volume= 0.065 af, Atten= 0%, Lag= 0.1 min Primary = 0.41 cfs @ 1.74 hrs, Volume= 0.065 af Routed to Pond 13P : SD-25, SD-26 Routing by Dyn-Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.0100 hrs Peak Elev= 585.17' @ 1.74 hrs Surf.Area= 0.000 ac Storage= 0.000 af Plug-Flow detention time= 0.1 min calculated for 0.065 af (100% of inflow) Center-of-Mass det. time= 0.1 min ( 158.0 - 157.9 ) Volume #1 Device #1 Invert 584.88' Avail.Storage 0.003 af Routing Primary Invert 584.88' Storage Description 15.0" Round SD-24 L= 111.3' S= 0.0150 '/' Outlet Devices 15.0" Vert. SD-24 C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.41 cfs @ 1.74 hrs HW=585.17' TW=580.74' (Dynamic Tailwater) 1=SD-24 (Orifice Controls 0.41 cfs @ 1.85 fps) Pond 14P: SD-24 Flow (cfs) Hydrograph Inflow Primary 0.41 cfs 0.44 0.42 0.4 0.38 0.36 0.34 0.32 0.3 0.28 0.26 0.24 0.22 0.2 0.18 0.16 0.14 0.12 0.1 0.08 0.06 0.04 0.02 0 Inflow Area=1.622 ac Peak Elev=585.17' Storage=0.000 af 0.41 cfs 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Time (hours) 15 16 17 18 19 20 21 22 23 24

Post-Developed (O-1B) NJ DEP 2-hr WQ Rainfall=1.25", P2=3.42" West Orange HydroCAD_Post Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Hydrograph for Pond 14P: SD-24 Time (hours) 0.00 0.50 1.00 1.50 2.00 2.50 3.00 3.50 4.00 4.50 5.00 5.50 6.00 6.50 7.00 7.50 8.00 8.50 9.00 9.50 10.00 10.50 11.00 11.50 12.00 12.50 13.00 13.50 14.00 14.50 15.00 15.50 16.00 16.50 17.00 17.50 18.00 18.50 19.00 19.50 20.00 20.50 21.00 21.50 22.00 22.50 23.00 23.50 24.00 Inflow (cfs) 0.00 0.00 0.02 0.39 0.39 0.30 0.18 0.09 0.05 0.03 0.02 0.01 0.01 0.01 0.01 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Storage Elevation (acre-feet) (feet) 0.000 584.88 0.000 584.88 0.000 584.95 0.000 585.17 0.000 585.17 0.000 585.13 0.000 585.07 0.000 585.02 0.000 584.98 0.000 584.96 0.000 584.94 0.000 584.93 0.000 584.92 0.000 584.92 0.000 584.91 0.000 584.91 0.000 584.91 0.000 584.91 0.000 584.90 0.000 584.90 0.000 584.90 0.000 584.90 0.000 584.90 0.000 584.90 0.000 584.90 0.000 584.90 0.000 584.89 0.000 584.89 0.000 584.89 0.000 584.89 0.000 584.89 0.000 584.89 0.000 584.89 0.000 584.89 0.000 584.89 0.000 584.89 0.000 584.89 0.000 584.89 0.000 584.89 0.000 584.89 0.000 584.89 0.000 584.89 0.000 584.89 0.000 584.89 0.000 584.89 0.000 584.89 0.000 584.89 0.000 584.89 0.000 584.89 Primary (cfs) 0.00 0.00 0.02 0.39 0.39 0.30 0.18 0.09 0.05 0.03 0.02 0.01 0.01 0.01 0.01 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Printed 5/13/2024 Page 40

Post-Developed (O-1B) NJ DEP 2-hr WQ Rainfall=1.25", P2=3.42" West Orange HydroCAD_Post Printed 5/13/2024 Page 41 Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Summary for Pond 17P: SD-23 Inflow Area = 1.305 ac, 24.67% Impervious, Inflow Depth > 0.46" for WQ event Inflow = 0.33 cfs @ 1.76 hrs, Volume= 0.050 af Outflow = 0.33 cfs @ 1.76 hrs, Volume= 0.050 af, Atten= 0%, Lag= 0.1 min Primary = 0.33 cfs @ 1.76 hrs, Volume= 0.050 af Routed to Pond 14P : SD-24 Routing by Dyn-Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.0100 hrs Peak Elev= 587.06' @ 1.76 hrs Surf.Area= 0.000 ac Storage= 0.000 af Plug-Flow detention time= 0.1 min calculated for 0.050 af (100% of inflow) Center-of-Mass det. time= 0.1 min ( 153.5 - 153.5 ) Volume #1 Device #1 Invert 586.80' Avail.Storage 0.003 af Routing Primary Invert 586.80' Storage Description 15.0" Round SD-23 L= 93.7' S= 0.0150 '/' Outlet Devices 15.0" Vert. SD-23 C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.33 cfs @ 1.76 hrs HW=587.06' TW=585.17' (Dynamic Tailwater) 1=SD-23 (Orifice Controls 0.33 cfs @ 1.75 fps) Pond 17P: SD-23 Hydrograph 0.36 Inflow Primary 0.33 cfs Inflow Area=1.305 ac Peak Elev=587.06' Storage=0.000 af 0.33 cfs 0.34 0.32 0.3 0.28 0.26 Flow (cfs) 0.24 0.22 0.2 0.18 0.16 0.14 0.12 0.1 0.08 0.06 0.04 0.02 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Time (hours) 15 16 17 18 19 20 21 22 23 24