J_2024 05 09_West Orange Stormwater Management Plan

Post-Developed (O-AquaShield) West Orange HydroCAD_Post NOAA 24-hr D 100-Year_Current Rainfall=9.23", P2=3.45" Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Printed 5/13/2024 Page 46 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 3S: PO-DA A Runoff Area=78,287 sf 12.62% Impervious Runoff Depth>7.18" Flow Length=491' Tc=18.2 min CN=WQ Runoff=9.73 cfs 1.076 af Runoff Area=18,459 sf 73.95% Impervious Runoff Depth>8.56" Flow Length=180' Slope=0.0160 '/' Tc=8.0 min CN=WQ Runoff=3.42 cfs 0.302 af Subcatchment 15S: PO-DA M Pond 4P: AquaShield Inflow=11.79 cfs 1.378 af Primary=11.79 cfs 1.378 af Total Runoff Area = 2.221 ac Runoff Volume = 1.378 af Average Runoff Depth = 7.45" 75.68% Pervious = 1.681 ac 24.32% Impervious = 0.540 ac

Post-Developed (O-AquaShield) West Orange HydroCAD_Post NOAA 24-hr D 100-Year_Current Rainfall=9.23", P2=3.45" Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Printed 5/13/2024 Page 47 Summary for Subcatchment 3S: PO-DA A Runoff = 9.73 cfs @ 12.27 hrs, Volume= Routed to Pond 4P : AquaShield 1.076 af, Depth> 7.18" 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) 9,878 14,245 39,395 14,769 78,287 68,409 9,878 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 87.38% Pervious Area 12.62% 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" 0.7 67 0.0540 1.63 Shallow Concentrated Flow, Shallow Concentrated Flow Short Grass Pasture Kv= 7.0 fps 0.1 43 0.2810 8.53 Shallow Concentrated Flow, Gravel Shallow Concentrated Flow Unpaved Kv= 16.1 fps 3.5 281 0.0069 1.34 Shallow Concentrated Flow, Gravel Shallow Concentrated Flow Unpaved Kv= 16.1 fps 18.2 491 Total

Post-Developed (O-AquaShield) NOAA 24-hr D 100-Year_Current Rainfall=9.23", P2=3.45" West Orange HydroCAD_Post Printed 5/13/2024 Page 48 Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Subcatchment 3S: PO-DA A Hydrograph Runoff 9.73 cfs 10 NOAA 24-hr D 100-Year_Current Rainfall=9.23" P2=3.45" Runoff Area=78,287 sf Runoff Volume=1.076 af Runoff Depth>7.18" Flow Length=491' Tc=18.2 min CN=WQ 9 8 Flow (cfs) 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_Post NOAA 24-hr D 100-Year_Current Rainfall=9.23", P2=3.45" Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Hydrograph for Subcatchment 3S: PO-DA A 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 0.00 4.50 0.56 0.01 5.00 0.63 0.02 5.50 0.71 0.04 6.00 0.79 0.06 6.50 0.88 0.09 7.00 0.97 0.12 7.50 1.08 0.17 8.00 1.20 0.22 8.50 1.33 0.28 9.00 1.46 0.36 9.50 1.63 0.45 10.00 1.83 0.58 10.50 2.07 0.74 11.00 2.40 0.98 11.50 2.93 1.39 12.00 4.42 2.66 12.50 6.30 4.37 13.00 6.83 4.87 13.50 7.16 5.18 14.00 7.40 5.41 14.50 7.60 5.60 15.00 7.77 5.75 15.50 7.90 5.89 16.00 8.03 6.01 16.50 8.15 6.12 17.00 8.26 6.22 17.50 8.35 6.32 18.00 8.44 6.40 18.50 8.52 6.48 19.00 8.60 6.55 19.50 8.67 6.62 20.00 8.75 6.69 20.50 8.82 6.76 21.00 8.88 6.82 21.50 8.95 6.89 22.00 9.01 6.94 22.50 9.07 7.00 23.00 9.12 7.06 23.50 9.18 7.11 24.00 9.23 7.16 Runoff (cfs) 0.00 0.00 0.01 0.01 0.02 0.02 0.02 0.03 0.04 0.05 0.07 0.08 0.09 0.11 0.14 0.17 0.21 0.24 0.28 0.35 0.46 0.58 0.85 1.43 3.75 5.24 1.90 1.17 0.83 0.70 0.57 0.48 0.44 0.41 0.37 0.34 0.30 0.28 0.27 0.26 0.25 0.24 0.23 0.22 0.22 0.21 0.20 0.19 0.18 Printed 5/13/2024 Page 49

Post-Developed (O-AquaShield) NOAA 24-hr D 100-Year_Current Rainfall=9.23", P2=3.45" West Orange HydroCAD_Post Printed 5/13/2024 Page 50 Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Summary for Subcatchment 15S: PO-DA M Runoff = 3.42 cfs @ 12.15 hrs, Volume= Routed to Pond 4P : AquaShield 0.302 af, Depth> 8.56" 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) 13,651 4,808 18,459 4,808 13,651 * CN 98 85 Description Impervious, Pavement, HSG D Yard Stone/Gravel Pad, HSG D Weighted Average 26.05% Pervious Area 73.95% 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" 0.5 80 0.0160 2.57 Shallow Concentrated Flow, Gravel Shallow Concentrated Flow Paved Kv= 20.3 fps 8.0 180 Total Subcatchment 15S: PO-DA M Hydrograph Runoff 3.42 cfs NOAA 24-hr D 100-Year_Current Rainfall=9.23" P2=3.45" Runoff Area=18,459 sf Runoff Volume=0.302 af Runoff Depth>8.56" Flow Length=180' Slope=0.0160 '/' Tc=8.0 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_Post NOAA 24-hr D 100-Year_Current Rainfall=9.23", P2=3.45" Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Hydrograph for Subcatchment 15S: PO-DA M 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 0.01 2.00 0.22 0.02 2.50 0.28 0.05 3.00 0.35 0.08 3.50 0.41 0.11 4.00 0.48 0.16 4.50 0.56 0.21 5.00 0.63 0.26 5.50 0.71 0.32 6.00 0.79 0.39 6.50 0.88 0.46 7.00 0.97 0.54 7.50 1.08 0.63 8.00 1.20 0.74 8.50 1.33 0.85 9.00 1.46 0.98 9.50 1.63 1.13 10.00 1.83 1.32 10.50 2.07 1.55 11.00 2.40 1.87 11.50 2.93 2.38 12.00 4.42 3.85 12.50 6.30 5.71 13.00 6.83 6.24 13.50 7.16 6.57 14.00 7.40 6.80 14.50 7.60 7.00 15.00 7.77 7.17 15.50 7.90 7.31 16.00 8.03 7.43 16.50 8.15 7.55 17.00 8.26 7.66 17.50 8.35 7.75 18.00 8.44 7.84 18.50 8.52 7.92 19.00 8.60 8.00 19.50 8.67 8.07 20.00 8.75 8.14 20.50 8.82 8.21 21.00 8.88 8.28 21.50 8.95 8.34 22.00 9.01 8.41 22.50 9.07 8.47 23.00 9.12 8.52 23.50 9.18 8.58 24.00 9.23 8.63 Runoff (cfs) 0.00 0.00 0.01 0.02 0.03 0.03 0.03 0.04 0.04 0.05 0.05 0.05 0.05 0.06 0.07 0.08 0.09 0.10 0.11 0.13 0.16 0.19 0.29 0.48 1.74 0.76 0.39 0.25 0.19 0.16 0.13 0.11 0.11 0.10 0.09 0.08 0.07 0.07 0.06 0.06 0.06 0.06 0.06 0.05 0.05 0.05 0.05 0.05 0.04 Printed 5/13/2024 Page 51

Post-Developed (O-AquaShield) NOAA 24-hr D 100-Year_Current Rainfall=9.23", P2=3.45" West Orange HydroCAD_Post Printed 5/13/2024 Page 52 Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Summary for Pond 4P: AquaShield Inflow Area = Inflow = Primary = 2.221 ac, 24.32% Impervious, Inflow Depth > 7.45" for 100-Year_Current event 11.79 cfs @ 12.23 hrs, Volume= 1.378 af 11.79 cfs @ 12.23 hrs, Volume= 1.378 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 4P: AquaShield Hydrograph 13 Inflow Primary 11.79 cfs Inflow Area=2.221 ac 11.79 cfs 12 11 10 9 Flow (cfs) 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_Post NOAA 24-hr D 100-Year_Current Rainfall=9.23", P2=3.45" Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Hydrograph for Pond 4P: 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 0.03 0.04 0.05 0.06 0.07 0.08 0.10 0.11 0.13 0.15 0.17 0.21 0.25 0.29 0.34 0.39 0.49 0.62 0.77 1.14 1.90 5.48 6.00 2.29 1.42 1.02 0.86 0.70 0.59 0.55 0.51 0.46 0.42 0.37 0.34 0.33 0.32 0.31 0.30 0.29 0.28 0.27 0.26 0.25 0.23 0.22 Primary (cfs) 0.00 0.00 0.02 0.03 0.04 0.05 0.06 0.07 0.08 0.10 0.11 0.13 0.15 0.17 0.21 0.25 0.29 0.34 0.39 0.49 0.62 0.77 1.14 1.90 5.48 6.00 2.29 1.42 1.02 0.86 0.70 0.59 0.55 0.51 0.46 0.42 0.37 0.34 0.33 0.32 0.31 0.30 0.29 0.28 0.27 0.26 0.25 0.23 0.22 Printed 5/13/2024 Page 53

Post-Developed (O-AquaShield) West Orange HydroCAD_Post NOAA 24-hr D 100-Year_Future Rainfall=11.58", P2=4.07" Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Printed 5/13/2024 Page 54 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 3S: PO-DA A Runoff Area=78,287 sf 12.62% Impervious Runoff Depth>9.45" Flow Length=491' Tc=17.1 min CN=WQ Runoff=12.98 cfs 1.415 af Runoff Area=18,459 sf 73.95% Impervious Runoff Depth>10.90" Flow Length=180' Slope=0.0160 '/' Tc=7.4 min CN=WQ Runoff=4.42 cfs 0.385 af Subcatchment 15S: PO-DA M Pond 4P: AquaShield Inflow=15.60 cfs 1.800 af Primary=15.60 cfs 1.800 af Total Runoff Area = 2.221 ac Runoff Volume = 1.800 af Average Runoff Depth = 9.73" 75.68% Pervious = 1.681 ac 24.32% Impervious = 0.540 ac

Post-Developed (O-AquaShield) West Orange HydroCAD_Post NOAA 24-hr D 100-Year_Future Rainfall=11.58", P2=4.07" Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Printed 5/13/2024 Page 55 Summary for Subcatchment 3S: PO-DA A Runoff = 12.98 cfs @ 12.25 hrs, Volume= Routed to Pond 4P : AquaShield 1.415 af, Depth> 9.45" 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) 9,878 14,245 39,395 14,769 78,287 68,409 9,878 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 87.38% Pervious Area 12.62% 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" 0.7 67 0.0540 1.63 Shallow Concentrated Flow, Shallow Concentrated Flow Short Grass Pasture Kv= 7.0 fps 0.1 43 0.2810 8.53 Shallow Concentrated Flow, Gravel Shallow Concentrated Flow Unpaved Kv= 16.1 fps 3.5 281 0.0069 1.34 Shallow Concentrated Flow, Gravel Shallow Concentrated Flow Unpaved Kv= 16.1 fps 17.1 491 Total