J_2024 05 09_West Orange Stormwater Management Plan

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 33 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 0.05 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 0.00 5.00 0.63 0.01 5.50 0.71 0.02 6.00 0.79 0.04 6.50 0.88 0.06 7.00 0.97 0.09 7.50 1.08 0.13 8.00 1.20 0.17 8.50 1.33 0.23 9.00 1.46 0.30 9.50 1.63 0.38 10.00 1.83 0.50 10.50 2.07 0.65 11.00 2.40 0.87 11.50 2.93 1.26 12.00 4.42 2.48 12.50 6.30 4.16 13.00 6.83 4.65 13.50 7.16 4.96 14.00 7.40 5.18 14.50 7.60 5.37 15.00 7.77 5.52 15.50 7.90 5.65 16.00 8.03 5.77 16.50 8.15 5.88 17.00 8.26 5.99 17.50 8.35 6.08 18.00 8.44 6.16 18.50 8.52 6.24 19.00 8.60 6.31 19.50 8.67 6.38 20.00 8.75 6.45 20.50 8.82 6.52 21.00 8.88 6.58 21.50 8.95 6.64 22.00 9.01 6.70 22.50 9.07 6.76 23.00 9.12 6.81 23.50 9.18 6.86 24.00 9.23 6.91 Runoff (cfs) 0.00 0.00 0.00 0.01 0.01 0.01 0.01 0.01 0.02 0.03 0.04 0.05 0.06 0.08 0.11 0.14 0.17 0.20 0.24 0.31 0.41 0.52 0.80 1.38 4.50 3.41 1.55 0.99 0.74 0.62 0.51 0.44 0.40 0.37 0.34 0.31 0.27 0.25 0.25 0.24 0.23 0.22 0.21 0.21 0.20 0.19 0.18 0.17 0.17

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 34 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 > 6.89" for 100-Year_Current event 10.52 cfs @ 12.19 hrs, Volume= 0.968 af 10.52 cfs @ 12.19 hrs, Volume= 0.968 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 10.52 cfs Inflow Area=1.685 ac 11 10.52 cfs 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-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 35 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 0.01 0.01 0.01 0.01 0.01 0.02 0.03 0.04 0.05 0.06 0.08 0.11 0.14 0.17 0.20 0.24 0.31 0.41 0.52 0.80 1.38 4.50 3.41 1.55 0.99 0.74 0.62 0.51 0.44 0.40 0.37 0.34 0.31 0.27 0.25 0.25 0.24 0.23 0.22 0.21 0.21 0.20 0.19 0.18 0.17 0.17 Primary (cfs) 0.00 0.00 0.00 0.01 0.01 0.01 0.01 0.01 0.02 0.03 0.04 0.05 0.06 0.08 0.11 0.14 0.17 0.20 0.24 0.31 0.41 0.52 0.80 1.38 4.50 3.41 1.55 0.99 0.74 0.62 0.51 0.44 0.40 0.37 0.34 0.31 0.27 0.25 0.25 0.24 0.23 0.22 0.21 0.21 0.20 0.19 0.18 0.17 0.17

Post-Developed (O-1) 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 36 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>9.14" Flow Length=439' Tc=11.6 min CN=WQ Runoff=13.89 cfs 1.284 af Inflow=13.89 cfs 1.284 af Primary=13.89 cfs 1.284 af Total Runoff Area = 1.685 ac Runoff Volume = 1.284 af Average Runoff Depth = 9.14" 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_Future Rainfall=11.58", P2=4.07" Prepared by Burns & McDonnell Printed 5/13/2024 Page 37 HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Summary for Subcatchment 24S: PO-DA 7 Runoff = 13.89 cfs @ 12.19 hrs, Volume= Routed to Pond 22P : O-1 1.284 af, Depth> 9.14" 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) 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 100-Year_Future Rainfall=11.58", P2=4.07" Prepared by Burns & McDonnell Printed 5/13/2024 Page 38 HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Subcatchment 24S: PO-DA 7 Hydrograph Runoff 15 13.89 cfs 14 NOAA 24-hr D 100-Year_Future Rainfall=11.58" P2=4.07" Runoff Area=73,407 sf Runoff Volume=1.284 af Runoff Depth>9.14" Flow Length=439' Tc=11.6 min CN=WQ 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-1) 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 39 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 0.06 0.00 1.00 0.13 0.00 1.50 0.20 0.00 2.00 0.28 0.00 2.50 0.36 0.00 3.00 0.44 0.00 3.50 0.52 0.00 4.00 0.61 0.01 4.50 0.70 0.02 5.00 0.79 0.04 5.50 0.89 0.06 6.00 0.99 0.09 6.50 1.10 0.13 7.00 1.22 0.18 7.50 1.35 0.24 8.00 1.50 0.32 8.50 1.66 0.40 9.00 1.84 0.50 9.50 2.04 0.63 10.00 2.30 0.80 10.50 2.59 1.01 11.00 3.01 1.32 11.50 3.67 1.85 12.00 5.55 3.47 12.50 7.91 5.66 13.00 8.57 6.28 13.50 8.99 6.68 14.00 9.28 6.96 14.50 9.54 7.20 15.00 9.74 7.40 15.50 9.92 7.57 16.00 10.08 7.72 16.50 10.23 7.86 17.00 10.36 7.99 17.50 10.48 8.11 18.00 10.59 8.22 18.50 10.69 8.31 19.00 10.79 8.41 19.50 10.88 8.50 20.00 10.97 8.59 20.50 11.06 8.67 21.00 11.14 8.75 21.50 11.22 8.83 22.00 11.30 8.90 22.50 11.38 8.98 23.00 11.45 9.05 23.50 11.52 9.11 24.00 11.58 9.17 Runoff (cfs) 0.00 0.00 0.01 0.01 0.01 0.01 0.02 0.03 0.04 0.06 0.08 0.09 0.11 0.14 0.18 0.22 0.26 0.30 0.35 0.45 0.58 0.73 1.12 1.90 6.15 4.29 1.99 1.27 0.94 0.80 0.65 0.56 0.52 0.48 0.43 0.39 0.35 0.33 0.31 0.30 0.29 0.28 0.27 0.26 0.25 0.24 0.23 0.22 0.21

Post-Developed (O-1) 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 40 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 > 9.14" for 100-Year_Future event 13.89 cfs @ 12.19 hrs, Volume= 1.284 af 13.89 cfs @ 12.19 hrs, Volume= 1.284 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 13.89 cfs 15 Inflow Area=1.685 ac 13.89 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-1) 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 41 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 0.01 0.01 0.01 0.01 0.02 0.03 0.04 0.06 0.08 0.09 0.11 0.14 0.18 0.22 0.26 0.30 0.35 0.45 0.58 0.73 1.12 1.90 6.15 4.29 1.99 1.27 0.94 0.80 0.65 0.56 0.52 0.48 0.43 0.39 0.35 0.33 0.31 0.30 0.29 0.28 0.27 0.26 0.25 0.24 0.23 0.22 0.21 Primary (cfs) 0.00 0.00 0.01 0.01 0.01 0.01 0.02 0.03 0.04 0.06 0.08 0.09 0.11 0.14 0.18 0.22 0.26 0.30 0.35 0.45 0.58 0.73 1.12 1.90 6.15 4.29 1.99 1.27 0.94 0.80 0.65 0.56 0.52 0.48 0.43 0.39 0.35 0.33 0.31 0.30 0.29 0.28 0.27 0.26 0.25 0.24 0.23 0.22 0.21

APPENDIX B.3- PRE-DEVELOPED OUTFALL = O-2