J_2024 05 09_West Orange Stormwater Management Plan

Post-Developed (O-AquaShield) West Orange HydroCAD_Pre NOAA 24-hr D 2-Year_Current Rainfall=3.45", P2=3.45" Prepared by Burns & McDonnell Printed 5/13/2024 Page 8 HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Subcatchment 22S: PO-DA 6 Hydrograph Runoff 3.47 cfs NOAA 24-hr D 2-Year_Current Rainfall=3.45" P2=3.45" Runoff Area=96,853 sf Runoff Volume=0.377 af Runoff Depth>2.04" Flow Length=491' Tc=18.1 min CN=WQ Flow (cfs) 3 2 1 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-AquaShield) West Orange HydroCAD_Pre NOAA 24-hr D 2-Year_Current Rainfall=3.45", P2=3.45" Prepared by Burns & McDonnell Printed 5/13/2024 Page 9 HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Hydrograph for Subcatchment 22S: PO-DA 6 Time Precip. Excess (hours) (inches) (inches) 0.00 0.00 0.00 0.50 0.02 0.00 1.00 0.04 0.00 1.50 0.06 0.00 2.00 0.08 0.00 2.50 0.11 0.00 3.00 0.13 0.00 3.50 0.16 0.00 4.00 0.18 0.00 4.50 0.21 0.00 5.00 0.24 0.00 5.50 0.26 0.00 6.00 0.29 0.00 6.50 0.33 0.00 7.00 0.36 0.00 7.50 0.40 0.00 8.00 0.45 0.00 8.50 0.50 0.01 9.00 0.55 0.02 9.50 0.61 0.03 10.00 0.68 0.05 10.50 0.77 0.08 11.00 0.90 0.13 11.50 1.09 0.22 12.00 1.65 0.55 12.50 2.36 1.07 13.00 2.55 1.22 13.50 2.68 1.32 14.00 2.77 1.39 14.50 2.84 1.46 15.00 2.90 1.51 15.50 2.95 1.55 16.00 3.00 1.59 16.50 3.05 1.63 17.00 3.09 1.66 17.50 3.12 1.69 18.00 3.16 1.72 18.50 3.19 1.75 19.00 3.21 1.77 19.50 3.24 1.79 20.00 3.27 1.82 20.50 3.29 1.84 21.00 3.32 1.86 21.50 3.34 1.88 22.00 3.37 1.90 22.50 3.39 1.92 23.00 3.41 1.94 23.50 3.43 1.96 24.00 3.45 1.97 Runoff (cfs) 0.00 0.00 0.00 0.00 0.00 0.01 0.01 0.01 0.01 0.02 0.02 0.02 0.02 0.02 0.03 0.03 0.04 0.05 0.06 0.08 0.11 0.15 0.23 0.42 1.22 1.93 0.73 0.46 0.33 0.28 0.23 0.19 0.18 0.16 0.15 0.14 0.12 0.11 0.11 0.11 0.10 0.10 0.10 0.09 0.09 0.08 0.08 0.08 0.07

Post-Developed (O-AquaShield) West Orange HydroCAD_Pre NOAA 24-hr D 2-Year_Current Rainfall=3.45", P2=3.45" Prepared by Burns & McDonnell Printed 5/13/2024 Page 10 HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Summary for Subcatchment 23S: PO-DA 8 Runoff = 1.07 cfs @ 12.15 hrs, Volume= Routed to Pond 20P : O-AquaShield 0.091 af, Depth> 2.83" Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-24.00 hrs, dt= 0.0100 hrs NOAA 24-hr D 2-Year_Current Rainfall=3.45", P2=3.45" Area (sf) 11,671 5,115 16,786 5,115 11,671 * CN 98 85 Description Impervious, Pavement, HSG D Yard Stone/Gravel Pad, HSG D Weighted Average 30.47% Pervious Area 69.53% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 7.5 100 0.0160 0.22 Sheet Flow, Gravel Sheet Flow n= 0.100 P2= 3.45" 0.6 78 0.0165 2.07 Shallow Concentrated Flow, Shallow Concentrated Flow Unpaved Kv= 16.1 fps 8.1 178 Total Subcatchment 23S: PO-DA 8 Hydrograph Runoff 1.07 cfs NOAA 24-hr D 2-Year_Current Rainfall=3.45" P2=3.45" Runoff Area=16,786 sf Runoff Volume=0.091 af Runoff Depth>2.83" Flow Length=178' Tc=8.1 min CN=WQ Flow (cfs) 1 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-AquaShield) West Orange HydroCAD_Pre NOAA 24-hr D 2-Year_Current Rainfall=3.45", P2=3.45" Prepared by Burns & McDonnell Printed 5/13/2024 Page 11 HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Hydrograph for Subcatchment 23S: PO-DA 8 Time Precip. Excess (hours) (inches) (inches) 0.00 0.00 0.00 0.50 0.02 0.00 1.00 0.04 0.00 1.50 0.06 0.00 2.00 0.08 0.00 2.50 0.11 0.00 3.00 0.13 0.00 3.50 0.16 0.00 4.00 0.18 0.00 4.50 0.21 0.01 5.00 0.24 0.02 5.50 0.26 0.02 6.00 0.29 0.03 6.50 0.33 0.05 7.00 0.36 0.06 7.50 0.40 0.08 8.00 0.45 0.11 8.50 0.50 0.13 9.00 0.55 0.17 9.50 0.61 0.21 10.00 0.68 0.26 10.50 0.77 0.32 11.00 0.90 0.42 11.50 1.09 0.58 12.00 1.65 1.08 12.50 2.36 1.73 13.00 2.55 1.92 13.50 2.68 2.04 14.00 2.77 2.12 14.50 2.84 2.20 15.00 2.90 2.26 15.50 2.95 2.31 16.00 3.00 2.35 16.50 3.05 2.39 17.00 3.09 2.43 17.50 3.12 2.47 18.00 3.16 2.50 18.50 3.19 2.53 19.00 3.21 2.56 19.50 3.24 2.58 20.00 3.27 2.61 20.50 3.29 2.64 21.00 3.32 2.66 21.50 3.34 2.68 22.00 3.37 2.71 22.50 3.39 2.73 23.00 3.41 2.75 23.50 3.43 2.77 24.00 3.45 2.79 Runoff (cfs) 0.00 0.00 0.00 0.00 0.00 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.02 0.02 0.02 0.03 0.03 0.04 0.05 0.05 0.08 0.14 0.53 0.24 0.13 0.08 0.06 0.05 0.04 0.04 0.03 0.03 0.03 0.03 0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.01 0.01

Post-Developed (O-AquaShield) West Orange HydroCAD_Pre NOAA 24-hr D 2-Year_Current Rainfall=3.45", P2=3.45" Prepared by Burns & McDonnell Printed 5/13/2024 Page 12 HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Summary for Pond 20P: O-AquaShield Inflow Area = Inflow = Primary = 2.609 ac, 26.54% Impervious, Inflow Depth > 2.15" for 2-Year_Current event 4.09 cfs @ 12.24 hrs, Volume= 0.468 af 4.09 cfs @ 12.24 hrs, Volume= 0.468 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 20P: O-AquaShield Hydrograph Inflow Primary 4.09 cfs Inflow Area=2.609 ac 4.09 cfs 4 Flow (cfs) 3 2 1 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-AquaShield) West Orange HydroCAD_Pre NOAA 24-hr D 2-Year_Current Rainfall=3.45", P2=3.45" Prepared by Burns & McDonnell Printed 5/13/2024 Page 13 HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Hydrograph for Pond 20P: O-AquaShield 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 0.00 0.00 0.01 0.01 0.02 0.02 0.02 0.03 0.03 0.03 0.03 0.04 0.04 0.05 0.06 0.08 0.09 0.12 0.16 0.20 0.31 0.56 1.75 2.17 0.86 0.54 0.39 0.33 0.27 0.23 0.21 0.20 0.18 0.16 0.15 0.13 0.13 0.13 0.12 0.12 0.11 0.11 0.11 0.10 0.10 0.09 0.09 Primary (cfs) 0.00 0.00 0.00 0.00 0.01 0.01 0.02 0.02 0.02 0.03 0.03 0.03 0.03 0.04 0.04 0.05 0.06 0.08 0.09 0.12 0.16 0.20 0.31 0.56 1.75 2.17 0.86 0.54 0.39 0.33 0.27 0.23 0.21 0.20 0.18 0.16 0.15 0.13 0.13 0.13 0.12 0.12 0.11 0.11 0.11 0.10 0.10 0.09 0.09

Post-Developed (O-AquaShield) West Orange HydroCAD_Pre NOAA 24-hr D 2-Year_Future Rainfall=4.07", P2=4.07" Prepared by Burns & McDonnell Printed 5/13/2024 Page 14 HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Time span=0.00-24.00 hrs, dt=0.0100 hrs, 2401 points Runoff by SCS TR-20 method, UH=SCS, Weighted-Q Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Subcatchment 22S: PO-DA 6 Runoff Area=96,853 sf 19.09% Impervious Runoff Depth>2.57" Flow Length=491' Tc=17.0 min CN=WQ Runoff=4.50 cfs 0.477 af Subcatchment 23S: PO-DA 8 Runoff Area=16,786 sf 69.53% Impervious Runoff Depth>3.43" Flow Length=178' Tc=7.5 min CN=WQ Runoff=1.32 cfs 0.110 af Pond 20P: O-AquaShield Inflow=5.27 cfs 0.587 af Primary=5.27 cfs 0.587 af Total Runoff Area = 2.609 ac Runoff Volume = 0.587 af Average Runoff Depth = 2.70" 73.46% Pervious = 1.917 ac 26.54% Impervious = 0.692 ac

Post-Developed (O-AquaShield) West Orange HydroCAD_Pre NOAA 24-hr D 2-Year_Future Rainfall=4.07", P2=4.07" Prepared by Burns & McDonnell Printed 5/13/2024 Page 15 HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Summary for Subcatchment 22S: PO-DA 6 Runoff = 4.50 cfs @ 12.26 hrs, Volume= Routed to Pond 20P : O-AquaShield 0.477 af, Depth> 2.57" Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-24.00 hrs, dt= 0.0100 hrs NOAA 24-hr D 2-Year_Future Rainfall=4.07", P2=4.07" * Area (sf) 18,485 9,771 53,605 14,992 96,853 78,368 18,485 CN 98 80 85 73 Description Impervious, Pavement, HSG D >75% Grass cover, Good, HSG D Yard Stone/Gravel Pad, HSG D Brush, Good, HSG D Weighted Average 80.91% Pervious Area 19.09% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 12.8 100 0.0543 0.13 Sheet Flow, Sheet Flow Woods: Light underbrush n= 0.400 P2= 4.07" 0.5 67 0.0908 2.11 Shallow Concentrated Flow, Shallow Concentrated Flow Short Grass Pasture Kv= 7.0 fps 0.2 43 0.2813 3.71 Shallow Concentrated Flow, Shallow Concentrated Flow Short Grass Pasture Kv= 7.0 fps 3.5 281 0.0069 1.34 Shallow Concentrated Flow, Shallow Concentrated Flow Unpaved Kv= 16.1 fps 17.0 491 Total

Post-Developed (O-AquaShield) West Orange HydroCAD_Pre NOAA 24-hr D 2-Year_Future Rainfall=4.07", P2=4.07" Prepared by Burns & McDonnell Printed 5/13/2024 Page 16 HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Subcatchment 22S: PO-DA 6 Hydrograph 5 Runoff 4.50 cfs NOAA 24-hr D 2-Year_Future Rainfall=4.07" P2=4.07" Runoff Area=96,853 sf Runoff Volume=0.477 af Runoff Depth>2.57" Flow Length=491' Tc=17.0 min CN=WQ Flow (cfs) 4 3 2 1 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-AquaShield) West Orange HydroCAD_Pre NOAA 24-hr D 2-Year_Future Rainfall=4.07", P2=4.07" Prepared by Burns & McDonnell Printed 5/13/2024 Page 17 HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Hydrograph for Subcatchment 22S: PO-DA 6 Time Precip. Excess (hours) (inches) (inches) 0.00 0.00 0.00 0.50 0.02 0.00 1.00 0.05 0.00 1.50 0.07 0.00 2.00 0.10 0.00 2.50 0.12 0.00 3.00 0.15 0.00 3.50 0.18 0.00 4.00 0.21 0.00 4.50 0.25 0.00 5.00 0.28 0.00 5.50 0.31 0.00 6.00 0.35 0.00 6.50 0.39 0.00 7.00 0.43 0.00 7.50 0.48 0.01 8.00 0.53 0.02 8.50 0.58 0.03 9.00 0.65 0.04 9.50 0.72 0.06 10.00 0.81 0.09 10.50 0.91 0.13 11.00 1.06 0.20 11.50 1.29 0.33 12.00 1.95 0.76 12.50 2.78 1.41 13.00 3.01 1.60 13.50 3.16 1.72 14.00 3.26 1.81 14.50 3.35 1.89 15.00 3.42 1.95 15.50 3.49 2.00 16.00 3.54 2.05 16.50 3.59 2.10 17.00 3.64 2.14 17.50 3.68 2.18 18.00 3.72 2.21 18.50 3.76 2.24 19.00 3.79 2.27 19.50 3.82 2.30 20.00 3.86 2.33 20.50 3.89 2.36 21.00 3.92 2.38 21.50 3.95 2.41 22.00 3.97 2.43 22.50 4.00 2.46 23.00 4.02 2.48 23.50 4.05 2.50 24.00 4.07 2.52 Runoff (cfs) 0.00 0.00 0.00 0.00 0.01 0.01 0.01 0.02 0.02 0.02 0.02 0.02 0.02 0.03 0.04 0.05 0.06 0.07 0.09 0.11 0.15 0.20 0.32 0.57 1.65 2.29 0.88 0.55 0.40 0.34 0.28 0.24 0.22 0.20 0.18 0.17 0.15 0.14 0.13 0.13 0.12 0.12 0.12 0.11 0.11 0.10 0.10 0.09 0.09