J_2024 05 09_West Orange Stormwater Management Plan

Post-Developed (O-1) West Orange HydroCAD_Pre NOAA 24-hr D 10-Year_Current Rainfall=5.37", P2=3.45" Prepared by Burns & McDonnell Printed 5/13/2024 Page 23 HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Hydrograph for Pond 22P: O-1 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 0.00 0.00 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.02 0.02 0.03 0.05 0.06 0.07 0.10 0.15 0.20 0.32 0.60 2.11 1.75 0.81 0.52 0.39 0.33 0.27 0.23 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 Primary (cfs) 0.00 0.00 0.00 0.00 0.00 0.00 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.02 0.02 0.03 0.05 0.06 0.07 0.10 0.15 0.20 0.32 0.60 2.11 1.75 0.81 0.52 0.39 0.33 0.27 0.23 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

Post-Developed (O-1) West Orange HydroCAD_Pre NOAA 24-hr D 10-Year_Future Rainfall=6.36", P2=4.07" Prepared by Burns & McDonnell Printed 5/13/2024 Page 24 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 24S: PO-DA 7 Pond 22P: O-1 Runoff Area=73,407 sf 5.92% Impervious Runoff Depth>4.22" Flow Length=439' Tc=11.6 min CN=WQ Runoff=6.61 cfs 0.592 af Inflow=6.61 cfs 0.592 af Primary=6.61 cfs 0.592 af Total Runoff Area = 1.685 ac Runoff Volume = 0.592 af Average Runoff Depth = 4.22" 94.08% Pervious = 1.585 ac 5.92% Impervious = 0.100 ac

Post-Developed (O-1) West Orange HydroCAD_Pre NOAA 24-hr D 10-Year_Future Rainfall=6.36", P2=4.07" Prepared by Burns & McDonnell Printed 5/13/2024 Page 25 HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Summary for Subcatchment 24S: PO-DA 7 Runoff = 6.61 cfs @ 12.19 hrs, Volume= Routed to Pond 22P : O-1 0.592 af, Depth> 4.22" 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 10-Year_Future Rainfall=6.36", P2=4.07" * Area (sf) 4,346 29,340 22,892 16,829 73,407 69,061 4,346 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 94.08% Pervious Area 5.92% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.2 49 0.0791 0.13 Sheet Flow, Sheet Flow Woods: Light underbrush n= 0.400 P2= 4.07" 1.9 151 0.0071 1.36 Shallow Concentrated Flow, Shallow Concentrated Flow Unpaved Kv= 16.1 fps 3.5 239 0.0260 1.13 Shallow Concentrated Flow, Shallow Concentrated Flow Short Grass Pasture Kv= 7.0 fps 11.6 439 Total

Post-Developed (O-1) West Orange HydroCAD_Pre NOAA 24-hr D 10-Year_Future Rainfall=6.36", P2=4.07" Prepared by Burns & McDonnell Printed 5/13/2024 Page 26 HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Subcatchment 24S: PO-DA 7 Hydrograph Runoff 7 6.61 cfs NOAA 24-hr D 10-Year_Future Rainfall=6.36" P2=4.07" Runoff Area=73,407 sf Runoff Volume=0.592 af Runoff Depth>4.22" Flow Length=439' Tc=11.6 min CN=WQ 6 Flow (cfs) 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-1) West Orange HydroCAD_Pre NOAA 24-hr D 10-Year_Future Rainfall=6.36", P2=4.07" Prepared by Burns & McDonnell Printed 5/13/2024 Page 27 HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Hydrograph for Subcatchment 24S: PO-DA 7 Time Precip. Excess (hours) (inches) (inches) 0.00 0.00 0.00 0.50 0.04 0.00 1.00 0.07 0.00 1.50 0.11 0.00 2.00 0.15 0.00 2.50 0.20 0.00 3.00 0.24 0.00 3.50 0.29 0.00 4.00 0.33 0.00 4.50 0.38 0.00 5.00 0.43 0.00 5.50 0.49 0.00 6.00 0.54 0.00 6.50 0.60 0.01 7.00 0.67 0.02 7.50 0.74 0.03 8.00 0.83 0.05 8.50 0.91 0.07 9.00 1.01 0.10 9.50 1.12 0.14 10.00 1.26 0.20 10.50 1.42 0.28 11.00 1.65 0.40 11.50 2.02 0.61 12.00 3.05 1.35 12.50 4.34 2.41 13.00 4.71 2.73 13.50 4.94 2.93 14.00 5.10 3.07 14.50 5.24 3.20 15.00 5.35 3.30 15.50 5.45 3.38 16.00 5.53 3.46 16.50 5.62 3.54 17.00 5.69 3.60 17.50 5.76 3.66 18.00 5.82 3.72 18.50 5.87 3.77 19.00 5.93 3.82 19.50 5.98 3.86 20.00 6.03 3.91 20.50 6.07 3.95 21.00 6.12 3.99 21.50 6.16 4.03 22.00 6.21 4.07 22.50 6.25 4.11 23.00 6.29 4.15 23.50 6.32 4.18 24.00 6.36 4.21 Runoff (cfs) 0.00 0.00 0.00 0.00 0.00 0.01 0.01 0.01 0.01 0.01 0.01 0.02 0.02 0.03 0.04 0.05 0.07 0.09 0.11 0.15 0.21 0.28 0.44 0.80 2.79 2.11 1.00 0.64 0.48 0.40 0.33 0.29 0.26 0.24 0.22 0.20 0.18 0.17 0.16 0.16 0.15 0.15 0.14 0.14 0.13 0.13 0.12 0.11 0.11

Post-Developed (O-1) West Orange HydroCAD_Pre NOAA 24-hr D 10-Year_Future Rainfall=6.36", P2=4.07" Prepared by Burns & McDonnell Printed 5/13/2024 Page 28 HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Summary for Pond 22P: O-1 Inflow Area = Inflow = Primary = 1.685 ac, 5.92% Impervious, Inflow Depth > 4.22" for 10-Year_Future event 6.61 cfs @ 12.19 hrs, Volume= 0.592 af 6.61 cfs @ 12.19 hrs, Volume= 0.592 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 22P: O-1 Hydrograph Inflow Primary 6.61 cfs 7 Inflow Area=1.685 ac 6.61 cfs 6 Flow (cfs) 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-1) West Orange HydroCAD_Pre NOAA 24-hr D 10-Year_Future Rainfall=6.36", P2=4.07" Prepared by Burns & McDonnell Printed 5/13/2024 Page 29 HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Hydrograph for Pond 22P: O-1 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 0.00 0.01 0.01 0.01 0.01 0.01 0.01 0.02 0.02 0.03 0.04 0.05 0.07 0.09 0.11 0.15 0.21 0.28 0.44 0.80 2.79 2.11 1.00 0.64 0.48 0.40 0.33 0.29 0.26 0.24 0.22 0.20 0.18 0.17 0.16 0.16 0.15 0.15 0.14 0.14 0.13 0.13 0.12 0.11 0.11 Primary (cfs) 0.00 0.00 0.00 0.00 0.00 0.01 0.01 0.01 0.01 0.01 0.01 0.02 0.02 0.03 0.04 0.05 0.07 0.09 0.11 0.15 0.21 0.28 0.44 0.80 2.79 2.11 1.00 0.64 0.48 0.40 0.33 0.29 0.26 0.24 0.22 0.20 0.18 0.17 0.16 0.16 0.15 0.15 0.14 0.14 0.13 0.13 0.12 0.11 0.11

Post-Developed (O-1) 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 30 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 24S: PO-DA 7 Pond 22P: O-1 Runoff Area=73,407 sf 5.92% Impervious Runoff Depth>6.89" Flow Length=439' Tc=12.1 min CN=WQ Runoff=10.52 cfs 0.968 af Inflow=10.52 cfs 0.968 af Primary=10.52 cfs 0.968 af Total Runoff Area = 1.685 ac Runoff Volume = 0.968 af Average Runoff Depth = 6.89" 94.08% Pervious = 1.585 ac 5.92% Impervious = 0.100 ac

Post-Developed (O-1) 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 31 HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Summary for Subcatchment 24S: PO-DA 7 Runoff = 10.52 cfs @ 12.19 hrs, Volume= Routed to Pond 22P : O-1 0.968 af, Depth> 6.89" 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) 4,346 29,340 22,892 16,829 73,407 69,061 4,346 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 94.08% Pervious Area 5.92% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.7 49 0.0791 0.12 Sheet Flow, Sheet Flow Woods: Light underbrush n= 0.400 P2= 3.45" 1.9 151 0.0071 1.36 Shallow Concentrated Flow, Shallow Concentrated Flow Unpaved Kv= 16.1 fps 3.5 239 0.0260 1.13 Shallow Concentrated Flow, Shallow Concentrated Flow Short Grass Pasture Kv= 7.0 fps 12.1 439 Total

Post-Developed (O-1) 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 32 HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Subcatchment 24S: PO-DA 7 Hydrograph Runoff 11 10.52 cfs NOAA 24-hr D 100-Year_Current Rainfall=9.23" P2=3.45" Runoff Area=73,407 sf Runoff Volume=0.968 af Runoff Depth>6.89" Flow Length=439' Tc=12.1 min CN=WQ 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