J_2024 05 09_West Orange Stormwater Management Plan

Post-Developed (O-2) 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 Pond 21P: O-2 Inflow Area = Inflow = Primary = 1.212 ac, 14.94% Impervious, Inflow Depth > 1.66" for 2-Year_Current event 2.45 cfs @ 12.11 hrs, Volume= 0.167 af 2.45 cfs @ 12.11 hrs, Volume= 0.167 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 21P: O-2 Hydrograph Inflow Primary 2.45 cfs Inflow Area=1.212 ac 2.45 cfs Flow (cfs) 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-2) 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 Pond 21P: O-2 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 0.00 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 0.04 0.05 0.10 0.20 1.28 0.50 0.27 0.18 0.14 0.12 0.10 0.09 0.08 0.08 0.07 0.06 0.06 0.05 0.05 0.05 0.05 0.05 0.05 0.04 0.04 0.04 0.04 0.04 0.04 Primary (cfs) 0.00 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 0.01 0.01 0.02 0.02 0.02 0.03 0.04 0.05 0.10 0.20 1.28 0.50 0.27 0.18 0.14 0.12 0.10 0.09 0.08 0.08 0.07 0.06 0.06 0.05 0.05 0.05 0.05 0.05 0.05 0.04 0.04 0.04 0.04 0.04 0.04

Post-Developed (O-2) 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 12 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 21S: PO-DA 1 Pond 21P: O-2 Runoff Area=52,807 sf 14.94% Impervious Runoff Depth>2.15" Flow Length=341' Tc=3.7 min CN=WQ Runoff=3.19 cfs 0.217 af Inflow=3.19 cfs 0.217 af Primary=3.19 cfs 0.217 af Total Runoff Area = 1.212 ac Runoff Volume = 0.217 af Average Runoff Depth = 2.15" 85.06% Pervious = 1.031 ac 14.94% Impervious = 0.181 ac

Post-Developed (O-2) 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 13 HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Summary for Subcatchment 21S: PO-DA 1 Runoff = 3.19 cfs @ 12.11 hrs, Volume= Routed to Pond 21P : O-2 0.217 af, Depth> 2.15" 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) 7,888 19,498 2,304 23,117 52,807 44,919 7,888 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 85.06% Pervious Area 14.94% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 0.3 23 0.0352 1.45 Sheet Flow, Sheet Flow Smooth surfaces n= 0.011 P2= 4.07" 0.2 31 0.2437 2.47 Shallow Concentrated Flow, Shallow Concentrated Flow Woodland Kv= 5.0 fps 3.2 287 0.0462 1.50 Shallow Concentrated Flow, Shallow Concentrated Flow Short Grass Pasture Kv= 7.0 fps 3.7 341 Total

Post-Developed (O-2) 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 Subcatchment 21S: PO-DA 1 Hydrograph Runoff 3.19 cfs NOAA 24-hr D 2-Year_Future Rainfall=4.07" P2=4.07" Runoff Area=52,807 sf Runoff Volume=0.217 af Runoff Depth>2.15" Flow Length=341' Tc=3.7 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-2) 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 Hydrograph for Subcatchment 21S: PO-DA 1 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 0.00 8.00 0.53 0.00 8.50 0.58 0.00 9.00 0.65 0.01 9.50 0.72 0.02 10.00 0.81 0.03 10.50 0.91 0.06 11.00 1.06 0.10 11.50 1.29 0.19 12.00 1.95 0.53 12.50 2.78 1.09 13.00 3.01 1.26 13.50 3.16 1.37 14.00 3.26 1.45 14.50 3.35 1.52 15.00 3.42 1.58 15.50 3.49 1.62 16.00 3.54 1.67 16.50 3.59 1.71 17.00 3.64 1.75 17.50 3.68 1.78 18.00 3.72 1.81 18.50 3.76 1.84 19.00 3.79 1.87 19.50 3.82 1.90 20.00 3.86 1.92 20.50 3.89 1.95 21.00 3.92 1.97 21.50 3.95 2.00 22.00 3.97 2.02 22.50 4.00 2.04 23.00 4.02 2.06 23.50 4.05 2.08 24.00 4.07 2.10 Runoff (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 0.01 0.01 0.02 0.02 0.02 0.03 0.04 0.06 0.08 0.14 0.28 1.70 0.64 0.34 0.23 0.18 0.15 0.12 0.11 0.10 0.10 0.09 0.08 0.07 0.07 0.07 0.06 0.06 0.06 0.06 0.05 0.05 0.05 0.05 0.05 0.04

Post-Developed (O-2) 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 Summary for Pond 21P: O-2 Inflow Area = Inflow = Primary = 1.212 ac, 14.94% Impervious, Inflow Depth > 2.15" for 2-Year_Future event 3.19 cfs @ 12.11 hrs, Volume= 0.217 af 3.19 cfs @ 12.11 hrs, Volume= 0.217 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 21P: O-2 Hydrograph Inflow Primary 3.19 cfs Inflow Area=1.212 ac 3.19 cfs 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-2) 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 Pond 21P: O-2 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 0.01 0.01 0.02 0.02 0.02 0.03 0.04 0.06 0.08 0.14 0.28 1.70 0.64 0.34 0.23 0.18 0.15 0.12 0.11 0.10 0.10 0.09 0.08 0.07 0.07 0.07 0.06 0.06 0.06 0.06 0.05 0.05 0.05 0.05 0.05 0.04 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 0.01 0.01 0.02 0.02 0.02 0.03 0.04 0.06 0.08 0.14 0.28 1.70 0.64 0.34 0.23 0.18 0.15 0.12 0.11 0.10 0.10 0.09 0.08 0.07 0.07 0.07 0.06 0.06 0.06 0.06 0.05 0.05 0.05 0.05 0.05 0.04

Post-Developed (O-2) 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 18 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 21S: PO-DA 1 Pond 21P: O-2 Runoff Area=52,807 sf 14.94% Impervious Runoff Depth>3.24" Flow Length=341' Tc=3.7 min CN=WQ Runoff=4.81 cfs 0.327 af Inflow=4.81 cfs 0.327 af Primary=4.81 cfs 0.327 af Total Runoff Area = 1.212 ac Runoff Volume = 0.327 af Average Runoff Depth = 3.24" 85.06% Pervious = 1.031 ac 14.94% Impervious = 0.181 ac

Post-Developed (O-2) 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 19 HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Summary for Subcatchment 21S: PO-DA 1 Runoff = 4.81 cfs @ 12.11 hrs, Volume= Routed to Pond 21P : O-2 0.327 af, Depth> 3.24" 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_Current Rainfall=5.37", P2=3.45" * Area (sf) 7,888 19,498 2,304 23,117 52,807 44,919 7,888 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 85.06% Pervious Area 14.94% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 0.3 23 0.0352 1.33 Sheet Flow, Sheet Flow Smooth surfaces n= 0.011 P2= 3.45" 0.2 31 0.2437 2.47 Shallow Concentrated Flow, Shallow Concentrated Flow Woodland Kv= 5.0 fps 3.2 287 0.0462 1.50 Shallow Concentrated Flow, Shallow Concentrated Flow Short Grass Pasture Kv= 7.0 fps 3.7 341 Total