J_2024 05 09_West Orange Stormwater Management Plan

Post-Developed (O-AquaShield) West Orange HydroCAD_Pre NOAA 24-hr D 100-Year_Current Rainfall=9.23", P2=3.45" Prepared by Burns & McDonnell Printed 5/13/2024 Page 38 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>7.39" Flow Length=491' Tc=18.1 min CN=WQ Runoff=12.28 cfs 1.369 af Subcatchment 23S: PO-DA 8 Runoff Area=16,786 sf 69.53% Impervious Runoff Depth>8.49" Flow Length=178' Tc=8.1 min CN=WQ Runoff=3.09 cfs 0.273 af Pond 20P: O-AquaShield Inflow=14.11 cfs 1.642 af Primary=14.11 cfs 1.642 af Total Runoff Area = 2.609 ac Runoff Volume = 1.642 af Average Runoff Depth = 7.55" 73.46% Pervious = 1.917 ac 26.54% Impervious = 0.692 ac

Post-Developed (O-AquaShield) West Orange HydroCAD_Pre NOAA 24-hr D 100-Year_Current Rainfall=9.23", P2=3.45" Prepared by Burns & McDonnell Printed 5/13/2024 Page 39 HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Summary for Subcatchment 22S: PO-DA 6 Runoff = 12.28 cfs @ 12.26 hrs, Volume= Routed to Pond 20P : O-AquaShield 1.369 af, Depth> 7.39" 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 100-Year_Current Rainfall=9.23", P2=3.45" * 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) 13.9 100 0.0543 0.12 Sheet Flow, Sheet Flow Woods: Light underbrush n= 0.400 P2= 3.45" 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 18.1 491 Total

Post-Developed (O-AquaShield) West Orange HydroCAD_Pre NOAA 24-hr D 100-Year_Current Rainfall=9.23", P2=3.45" Prepared by Burns & McDonnell Printed 5/13/2024 Page 40 HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Subcatchment 22S: PO-DA 6 Hydrograph Runoff 13 12.28 cfs NOAA 24-hr D 100-Year_Current Rainfall=9.23" P2=3.45" Runoff Area=96,853 sf Runoff Volume=1.369 af Runoff Depth>7.39" Flow Length=491' Tc=18.1 min CN=WQ 12 11 10 Flow (cfs) 9 8 7 6 5 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 100-Year_Current Rainfall=9.23", P2=3.45" Prepared by Burns & McDonnell Printed 5/13/2024 Page 41 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 0.05 0.00 1.00 0.11 0.00 1.50 0.16 0.00 2.00 0.22 0.00 2.50 0.28 0.00 3.00 0.35 0.00 3.50 0.41 0.00 4.00 0.48 0.01 4.50 0.56 0.02 5.00 0.63 0.04 5.50 0.71 0.06 6.00 0.79 0.09 6.50 0.88 0.12 7.00 0.97 0.16 7.50 1.08 0.21 8.00 1.20 0.27 8.50 1.33 0.35 9.00 1.46 0.43 9.50 1.63 0.54 10.00 1.83 0.67 10.50 2.07 0.84 11.00 2.40 1.10 11.50 2.93 1.53 12.00 4.42 2.84 12.50 6.30 4.59 13.00 6.83 5.09 13.50 7.16 5.41 14.00 7.40 5.64 14.50 7.60 5.83 15.00 7.77 5.99 15.50 7.90 6.12 16.00 8.03 6.24 16.50 8.15 6.36 17.00 8.26 6.46 17.50 8.35 6.56 18.00 8.44 6.64 18.50 8.52 6.72 19.00 8.60 6.79 19.50 8.67 6.86 20.00 8.75 6.93 20.50 8.82 7.00 21.00 8.88 7.07 21.50 8.95 7.13 22.00 9.01 7.19 22.50 9.07 7.25 23.00 9.12 7.30 23.50 9.18 7.35 24.00 9.23 7.40 Runoff (cfs) 0.00 0.00 0.01 0.02 0.03 0.04 0.04 0.05 0.07 0.09 0.10 0.12 0.14 0.16 0.20 0.24 0.28 0.33 0.38 0.47 0.61 0.75 1.10 1.83 4.78 6.54 2.37 1.45 1.03 0.87 0.71 0.60 0.55 0.51 0.47 0.42 0.38 0.34 0.33 0.32 0.31 0.30 0.29 0.28 0.27 0.26 0.25 0.23 0.22

Post-Developed (O-AquaShield) West Orange HydroCAD_Pre NOAA 24-hr D 100-Year_Current Rainfall=9.23", P2=3.45" Prepared by Burns & McDonnell Printed 5/13/2024 Page 42 HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Summary for Subcatchment 23S: PO-DA 8 Runoff = 3.09 cfs @ 12.15 hrs, Volume= Routed to Pond 20P : O-AquaShield 0.273 af, Depth> 8.49" 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 100-Year_Current Rainfall=9.23", 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 3.09 cfs NOAA 24-hr D 100-Year_Current Rainfall=9.23" P2=3.45" Runoff Area=16,786 sf Runoff Volume=0.273 af Runoff Depth>8.49" Flow Length=178' Tc=8.1 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 100-Year_Current Rainfall=9.23", P2=3.45" Prepared by Burns & McDonnell Printed 5/13/2024 Page 43 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 0.05 0.00 1.00 0.11 0.00 1.50 0.16 0.00 2.00 0.22 0.01 2.50 0.28 0.03 3.00 0.35 0.06 3.50 0.41 0.09 4.00 0.48 0.13 4.50 0.56 0.17 5.00 0.63 0.22 5.50 0.71 0.28 6.00 0.79 0.34 6.50 0.88 0.40 7.00 0.97 0.48 7.50 1.08 0.57 8.00 1.20 0.67 8.50 1.33 0.78 9.00 1.46 0.90 9.50 1.63 1.05 10.00 1.83 1.24 10.50 2.07 1.46 11.00 2.40 1.77 11.50 2.93 2.28 12.00 4.42 3.74 12.50 6.30 5.60 13.00 6.83 6.12 13.50 7.16 6.45 14.00 7.40 6.69 14.50 7.60 6.89 15.00 7.77 7.05 15.50 7.90 7.19 16.00 8.03 7.31 16.50 8.15 7.43 17.00 8.26 7.54 17.50 8.35 7.63 18.00 8.44 7.72 18.50 8.52 7.80 19.00 8.60 7.88 19.50 8.67 7.95 20.00 8.75 8.02 20.50 8.82 8.09 21.00 8.88 8.16 21.50 8.95 8.22 22.00 9.01 8.29 22.50 9.07 8.34 23.00 9.12 8.40 23.50 9.18 8.45 24.00 9.23 8.51 Runoff (cfs) 0.00 0.00 0.01 0.02 0.02 0.03 0.03 0.03 0.04 0.04 0.04 0.05 0.05 0.05 0.06 0.07 0.08 0.09 0.10 0.12 0.15 0.17 0.26 0.43 1.56 0.70 0.36 0.23 0.17 0.15 0.12 0.10 0.10 0.09 0.08 0.07 0.06 0.06 0.06 0.06 0.05 0.05 0.05 0.05 0.05 0.05 0.04 0.04 0.04

Post-Developed (O-AquaShield) West Orange HydroCAD_Pre NOAA 24-hr D 100-Year_Current Rainfall=9.23", P2=3.45" Prepared by Burns & McDonnell Printed 5/13/2024 Page 44 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 > 7.55" for 100-Year_Current event 14.11 cfs @ 12.24 hrs, Volume= 1.642 af 14.11 cfs @ 12.24 hrs, Volume= 1.642 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 14.11 cfs 15 Inflow Area=2.609 ac 14.11 cfs 14 13 12 11 Flow (cfs) 10 9 8 7 6 5 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 100-Year_Current Rainfall=9.23", P2=3.45" Prepared by Burns & McDonnell Printed 5/13/2024 Page 45 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 0.02 0.04 0.06 0.07 0.07 0.09 0.11 0.12 0.14 0.16 0.18 0.22 0.26 0.31 0.36 0.42 0.47 0.59 0.75 0.93 1.36 2.26 6.34 7.23 2.73 1.68 1.20 1.01 0.83 0.70 0.65 0.60 0.55 0.49 0.44 0.41 0.39 0.38 0.37 0.35 0.34 0.33 0.31 0.30 0.29 0.28 0.26 Primary (cfs) 0.00 0.00 0.02 0.04 0.06 0.07 0.07 0.09 0.11 0.12 0.14 0.16 0.18 0.22 0.26 0.31 0.36 0.42 0.47 0.59 0.75 0.93 1.36 2.26 6.34 7.23 2.73 1.68 1.20 1.01 0.83 0.70 0.65 0.60 0.55 0.49 0.44 0.41 0.39 0.38 0.37 0.35 0.34 0.33 0.31 0.30 0.29 0.28 0.26

Post-Developed (O-AquaShield) West Orange HydroCAD_Pre NOAA 24-hr D 100-Year_Future Rainfall=11.58", P2=4.07" Prepared by Burns & McDonnell Printed 5/13/2024 Page 46 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>9.66" Flow Length=491' Tc=17.0 min CN=WQ Runoff=16.29 cfs 1.791 af Subcatchment 23S: PO-DA 8 Runoff Area=16,786 sf 69.53% Impervious Runoff Depth>10.83" Flow Length=178' Tc=7.5 min CN=WQ Runoff=4.01 cfs 0.348 af Pond 20P: O-AquaShield Inflow=18.67 cfs 2.138 af Primary=18.67 cfs 2.138 af Total Runoff Area = 2.609 ac Runoff Volume = 2.138 af Average Runoff Depth = 9.84" 73.46% Pervious = 1.917 ac 26.54% Impervious = 0.692 ac

Post-Developed (O-AquaShield) West Orange HydroCAD_Pre NOAA 24-hr D 100-Year_Future Rainfall=11.58", P2=4.07" Prepared by Burns & McDonnell Printed 5/13/2024 Page 47 HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Summary for Subcatchment 22S: PO-DA 6 Runoff = 16.29 cfs @ 12.25 hrs, Volume= Routed to Pond 20P : O-AquaShield 1.791 af, Depth> 9.66" 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 100-Year_Future Rainfall=11.58", 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