J_2024 05 09_West Orange Stormwater Management Plan

Post-Developed (O-1A) NOAA 24-hr D 10-Year_Future Rainfall=6.36", P2=4.07" West Orange HydroCAD_Post Printed 5/13/2024 Page 196 Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Pond 20P: SD-11, SD-12 Hydrograph Inflow Primary 4.39 cfs Inflow Area=1.308 ac Peak Elev=592.02' Storage=80 cf 4.38 cfs 4 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-1A) West Orange HydroCAD_Post NOAA 24-hr D 10-Year_Future Rainfall=6.36", P2=4.07" Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Hydrograph for Pond 20P: SD-11, SD-12 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 (cfs) 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.01 0.01 0.02 0.06 0.09 0.13 0.23 0.46 1.87 1.42 0.69 0.45 0.34 0.29 0.23 0.20 0.19 0.17 0.16 0.14 0.13 0.12 0.12 0.11 0.11 0.11 0.10 0.10 0.09 0.09 0.09 0.08 0.08 Storage Elevation (cubic-feet) (feet) 0 590.26 0 590.26 0 590.26 0 590.26 0 590.26 0 590.26 0 590.26 0 590.26 0 590.26 0 590.26 0 590.26 0 590.27 0 590.28 1 590.31 1 590.37 3 590.49 10 591.04 10 591.05 10 591.06 11 591.10 12 591.13 12 591.16 14 591.21 16 591.29 35 591.62 29 591.54 19 591.37 16 591.29 15 591.25 14 591.23 14 591.21 13 591.20 13 591.19 13 591.18 13 591.17 12 591.16 12 591.16 12 591.15 12 591.15 12 591.14 12 591.14 12 591.14 12 591.14 12 591.14 12 591.13 12 591.13 12 591.13 12 591.12 12 591.12 Primary (cfs) 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.01 0.01 0.02 0.05 0.09 0.13 0.23 0.45 1.82 1.43 0.69 0.45 0.34 0.29 0.24 0.20 0.19 0.17 0.16 0.14 0.13 0.12 0.12 0.11 0.11 0.11 0.10 0.10 0.09 0.09 0.09 0.08 0.08 Printed 5/13/2024 Page 197

Post-Developed (O-1A) NOAA 24-hr D 10-Year_Future Rainfall=6.36", P2=4.07" West Orange HydroCAD_Post Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Printed 5/13/2024 Page 198 Summary for Pond 23P: SD-01, SD-02 Inflow Area = 0.656 ac, 0.00% Impervious, Inflow Depth > 3.45" for 10-Year_Future event Inflow = 2.11 cfs @ 12.20 hrs, Volume= 0.189 af Outflow = 2.11 cfs @ 12.20 hrs, Volume= 0.187 af, Atten= 0%, Lag= 0.1 min Primary = 2.11 cfs @ 12.20 hrs, Volume= 0.187 af Routed to Pond 12P : SD-03, SD-04, SD-05 Routing by Dyn-Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.0100 hrs Peak Elev= 597.86' @ 12.20 hrs Surf.Area= 17 sf Storage= 97 cf Plug-Flow detention time= 9.5 min calculated for 0.187 af (99% of inflow) Center-of-Mass det. time= 3.4 min ( 843.3 - 839.8 ) Volume #1 #2 #3 Invert 602.00' 591.82' 598.38' Avail.Storage 5,354,109 cf 163 cf 25 cf #4 #5 598.06' 597.81' 118 cf 61 cf 5,354,476 cf Elevation (feet) 602.00 603.00 Surf.Area (sq-ft) 696,960 12,422,876 Elevation (feet) 591.82 602.00 Surf.Area (sq-ft) 16 16 Inc.Store (cubic-feet) 0 163 Cum.Store (cubic-feet) 0 163 Elevation (feet) 598.06 607.15 Surf.Area (sq-ft) 13 13 Inc.Store (cubic-feet) 0 118 Cum.Store (cubic-feet) 0 118 Device #1 Routing Primary Perim. (feet) 16.0 130.1 Storage Description Drainage Ditch Storage (Irregular)Listed below (Recalc) CB-1 (Prismatic) Listed below (Recalc) 12.0" Round SD-01 L= 31.6' S= 0.0100 '/' MH-01 (Prismatic) Listed below (Recalc) 12.0" Round SD-02 L= 78.0' S= 0.0100 '/' Total Available Storage Invert 597.04' Inc.Store (cubic-feet) 0 5,354,109 Cum.Store (cubic-feet) 0 5,354,109 Wet.Area (sq-ft) 696,960 698,289 Outlet Devices 12.0" Vert. SD-02 C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=2.11 cfs @ 12.20 hrs HW=597.86' TW=596.71' (Dynamic Tailwater) 1=SD-02 (Orifice Controls 2.11 cfs @ 3.08 fps)

Post-Developed (O-1A) NOAA 24-hr D 10-Year_Future Rainfall=6.36", P2=4.07" West Orange HydroCAD_Post Printed 5/13/2024 Page 199 Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Pond 23P: SD-01, SD-02 Hydrograph Inflow Primary 2.11 cfs Inflow Area=0.656 ac Peak Elev=597.86' Storage=97 cf 2.11 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-1A) West Orange HydroCAD_Post NOAA 24-hr D 10-Year_Future Rainfall=6.36", P2=4.07" Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Hydrograph for Pond 23P: SD-01, SD-02 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 (cfs) 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.01 0.01 0.02 0.03 0.04 0.06 0.11 0.22 0.82 0.75 0.35 0.23 0.17 0.14 0.12 0.10 0.09 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 Storage Elevation (cubic-feet) (feet) 0 591.82 0 591.82 0 591.82 0 591.82 0 591.82 0 591.82 0 591.82 0 591.82 0 591.82 0 591.82 0 591.83 0 591.84 1 591.87 2 591.93 3 592.03 6 592.18 11 592.51 25 593.39 50 594.93 85 597.12 85 597.14 85 597.16 86 597.20 87 597.27 91 597.50 91 597.48 88 597.33 87 597.27 87 597.24 86 597.22 86 597.21 86 597.19 86 597.19 86 597.18 86 597.18 86 597.17 85 597.16 85 597.16 85 597.16 85 597.15 85 597.15 85 597.15 85 597.15 85 597.15 85 597.14 85 597.14 85 597.14 85 597.14 85 597.13 Primary (cfs) 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.03 0.04 0.06 0.11 0.22 0.81 0.76 0.35 0.23 0.17 0.14 0.12 0.10 0.09 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 Printed 5/13/2024 Page 200

Post-Developed (O-1A) 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 201 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 Runoff Area=28,575 sf 0.00% Impervious Runoff Depth>5.98" Flow Length=298' Tc=13.3 min CN=WQ Runoff=3.52 cfs 0.327 af Subcatchment 4S: PO-DA B Runoff Area=6,403 sf 0.00% Impervious Runoff Depth>6.40" Flow Length=85' Slope=0.1773 '/' Tc=7.6 min CN=WQ Runoff=1.01 cfs 0.078 af Subcatchment 6S: PO-DA D Runoff Area=3,746 sf 0.00% Impervious Runoff Depth>6.19" Flow Length=66' Slope=0.2264 '/' Tc=5.6 min CN=WQ Runoff=0.62 cfs 0.044 af Subcatchment 8S: PO-DA F Runoff Area=10,281 sf 0.00% Impervious Runoff Depth>5.94" Flow Length=82' Slope=0.1736 '/' Tc=7.4 min CN=WQ Runoff=1.54 cfs 0.117 af Subcatchment 10S: PO-DA H Subcatchment 13S: PO-DA K Runoff Area=4,400 sf 30.68% Impervious Runoff Depth>7.06" Flow Length=239' Tc=14.3 min CN=WQ Runoff=0.59 cfs 0.059 af Subcatchment 14S: PO-DA L Runoff Area=7,972 sf 0.00% Impervious Runoff Depth>6.04" Flow Length=116' Tc=11.1 min CN=WQ Runoff=1.06 cfs 0.092 af Reach 3R: TD-01 Avg. Flow Depth=0.13' Max Vel=5.02 fps Inflow=1.01 cfs 0.078 af n=0.012 L=67.2' S=0.0298 '/' Capacity=30.28 cfs Outflow=1.01 cfs 0.078 af Reach 4R: TD-02 Avg. Flow Depth=0.10' Max Vel=4.12 fps Inflow=0.62 cfs 0.044 af n=0.012 L=34.0' S=0.0279 '/' Capacity=29.34 cfs Outflow=0.62 cfs 0.044 af Reach 5R: TD-03 Avg. Flow Depth=0.33' Max Vel=3.09 fps Inflow=1.54 cfs 0.117 af n=0.012 L=133.7' S=0.0044 '/' Capacity=11.66 cfs Outflow=1.53 cfs 0.117 af Reach 6R: TD-04 Avg. Flow Depth=0.17' Max Vel=4.21 fps Inflow=1.06 cfs 0.092 af n=0.012 L=54.6' S=0.0163 '/' Capacity=22.41 cfs Outflow=1.06 cfs 0.092 af Pond 7P: O-1A Inflow=7.72 cfs 0.716 af Primary=7.72 cfs 0.716 af Pond 12P: SD-03, SD-04, SD-05 Peak Elev=596.96' Storage=67 cf Inflow=4.29 cfs 0.404 af Outflow=4.29 cfs 0.403 af Pond 15P: SD-06, SD-07, SD-08 Peak Elev=594.99' Storage=77 cf Inflow=4.69 cfs 0.448 af Outflow=4.69 cfs 0.448 af Pond 16P: SD-09, SD-10 Peak Elev=594.10' Storage=123 cf Inflow=6.14 cfs 0.565 af Outflow=6.13 cfs 0.564 af Pond 20P: SD-11, SD-12 Peak Elev=592.45'

flow=4.69 cfs 0.448 af Outflow=4.69 cfs 0.448 af Pond 16P: SD-09, SD-10 Peak Elev=594.10' Storage=123 cf Inflow=6.14 cfs 0.565 af Outflow=6.13 cfs 0.564 af Pond 20P: SD-11, SD-12 Peak Elev=592.45' Storage=151 cf Inflow=7.18 cfs 0.656 af Outflow=7.15 cfs 0.656 af Pond 23P: SD-01, SD-02 Peak Elev=598.40' Storage=122 cf Inflow=3.52 cfs 0.327 af Outflow=3.51 cfs 0.325 af

Post-Developed (O-1A) 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 202 Total Runoff Area = 1.409 ac Runoff Volume = 0.718 af Average Runoff Depth = 6.12" 97.80% Pervious = 1.378 ac 2.20% Impervious = 0.031 ac

Post-Developed (O-1A) NOAA 24-hr D 100-Year_Current Rainfall=9.23", P2=3.45" West Orange HydroCAD_Post Printed 5/13/2024 Page 203 Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Summary for Subcatchment 4S: PO-DA B Runoff = 3.52 cfs @ 12.21 hrs, Volume= Routed to Pond 23P : SD-01, SD-02 0.327 af, Depth> 5.98" 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) 1,873 610 26,092 28,575 28,575 * CN 80 85 73 Description >75% Grass cover, Good, HSG D Yard Stone/Gravel Pad, HSG D Brush, Good, HSG D Weighted Average 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 11.3 100 0.0900 0.15 Sheet Flow, Sheet Flow Woods: Light underbrush n= 0.400 P2= 3.45" 0.3 64 0.1920 3.07 Shallow Concentrated Flow, Shallow Concentrated Flow Short Grass Pasture Kv= 7.0 fps 1.7 134 0.0094 1.34 8.07 Channel Flow, North Channel Area= 6.0 sf Perim= 9.3' r= 0.65' n= 0.080 Earth, long dense weeds 13.3 298 Total Subcatchment 4S: PO-DA B Hydrograph Runoff 3.52 cfs NOAA 24-hr D 100-Year_Current Rainfall=9.23" P2=3.45" Runoff Area=28,575 sf Runoff Volume=0.327 af Runoff Depth>5.98" Flow Length=298' Tc=13.3 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-1A) 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 4S: PO-DA B 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 0.00 5.50 0.71 0.00 6.00 0.79 0.00 6.50 0.88 0.01 7.00 0.97 0.02 7.50 1.08 0.04 8.00 1.20 0.06 8.50 1.33 0.09 9.00 1.46 0.14 9.50 1.63 0.19 10.00 1.83 0.27 10.50 2.07 0.38 11.00 2.40 0.55 11.50 2.93 0.86 12.00 4.42 1.91 12.50 6.30 3.44 13.00 6.83 3.89 13.50 7.16 4.18 14.00 7.40 4.39 14.50 7.60 4.57 15.00 7.77 4.72 15.50 7.90 4.84 16.00 8.03 4.95 16.50 8.15 5.06 17.00 8.26 5.16 17.50 8.35 5.24 18.00 8.44 5.32 18.50 8.52 5.39 19.00 8.60 5.46 19.50 8.67 5.53 20.00 8.75 5.60 20.50 8.82 5.66 21.00 8.88 5.72 21.50 8.95 5.78 22.00 9.01 5.84 22.50 9.07 5.89 23.00 9.12 5.94 23.50 9.18 5.99 24.00 9.23 6.04 Runoff (cfs) 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.01 0.01 0.02 0.03 0.04 0.06 0.08 0.11 0.14 0.23 0.42 1.41 1.31 0.58 0.37 0.27 0.23 0.19 0.16 0.15 0.14 0.13 0.11 0.10 0.09 0.09 0.09 0.09 0.08 0.08 0.08 0.07 0.07 0.07 0.06 0.06 Printed 5/13/2024 Page 204