J_2024 05 09_West Orange Stormwater Management Plan

Post-Developed (O-1B) NJ DEP 2-hr WQ Rainfall=1.25", P2=3.42" West Orange HydroCAD_Post Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Hydrograph for Pond 17P: SD-23 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 0.01 0.31 0.32 0.24 0.15 0.07 0.03 0.02 0.01 0.01 0.01 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 0.00 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 Storage Elevation (acre-feet) (feet) 0.000 586.80 0.000 586.80 0.000 586.84 0.000 587.05 0.000 587.06 0.000 587.03 0.000 586.97 0.000 586.92 0.000 586.88 0.000 586.86 0.000 586.85 0.000 586.84 0.000 586.84 0.000 586.83 0.000 586.83 0.000 586.82 0.000 586.82 0.000 586.82 0.000 586.82 0.000 586.82 0.000 586.82 0.000 586.81 0.000 586.81 0.000 586.81 0.000 586.81 0.000 586.81 0.000 586.81 0.000 586.81 0.000 586.81 0.000 586.81 0.000 586.81 0.000 586.81 0.000 586.81 0.000 586.81 0.000 586.81 0.000 586.81 0.000 586.81 0.000 586.81 0.000 586.81 0.000 586.81 0.000 586.81 0.000 586.81 0.000 586.81 0.000 586.81 0.000 586.81 0.000 586.81 0.000 586.81 0.000 586.81 0.000 586.81 Primary (cfs) 0.00 0.00 0.01 0.31 0.32 0.24 0.15 0.07 0.04 0.02 0.01 0.01 0.01 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 0.00 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 Printed 5/13/2024 Page 42

Post-Developed (O-1B) NJ DEP 2-hr WQ Rainfall=1.25", P2=3.42" West Orange HydroCAD_Post Printed 5/13/2024 Page 43 Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Summary for Pond 18P: SD-22 Inflow Area = 0.917 ac, 22.90% Impervious, Inflow Depth > 0.45" for WQ event Inflow = 0.23 cfs @ 1.70 hrs, Volume= 0.035 af Outflow = 0.23 cfs @ 1.70 hrs, Volume= 0.035 af, Atten= 0%, Lag= 0.1 min Primary = 0.23 cfs @ 1.70 hrs, Volume= 0.035 af Routed to Pond 17P : SD-23 Routing by Dyn-Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.0100 hrs Peak Elev= 588.69' @ 1.70 hrs Surf.Area= 0.000 ac Storage= 0.000 af Plug-Flow detention time= (not calculated: outflow precedes inflow) Center-of-Mass det. time= 0.1 min ( 146.6 - 146.6 ) Volume #1 Device #1 Invert 588.45' Avail.Storage 0.002 af Routing Primary Invert 588.45' Storage Description 12.0" Round SD-22 L= 127.3' S= 0.0150 '/' Outlet Devices 12.0" Vert. SD-22 C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.23 cfs @ 1.70 hrs HW=588.69' TW=587.06' (Dynamic Tailwater) 1=SD-22 (Orifice Controls 0.23 cfs @ 1.65 fps) Pond 18P: SD-22 Hydrograph 0.26 Inflow Primary 0.23 cfs Inflow Area=0.917 ac Peak Elev=588.69' Storage=0.000 af 0.23 cfs 0.24 0.22 0.2 0.18 Flow (cfs) 0.16 0.14 0.12 0.1 0.08 0.06 0.04 0.02 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-1B) NJ DEP 2-hr WQ Rainfall=1.25", P2=3.42" West Orange HydroCAD_Post Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Hydrograph for Pond 18P: SD-22 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 0.01 0.23 0.22 0.17 0.10 0.04 0.02 0.01 0.01 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 0.00 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 Storage Elevation (acre-feet) (feet) 0.000 588.45 0.000 588.45 0.000 588.49 0.000 588.68 0.000 588.68 0.000 588.65 0.000 588.60 0.000 588.55 0.000 588.52 0.000 588.50 0.000 588.49 0.000 588.48 0.000 588.48 0.000 588.47 0.000 588.47 0.000 588.47 0.000 588.47 0.000 588.47 0.000 588.46 0.000 588.46 0.000 588.46 0.000 588.46 0.000 588.46 0.000 588.46 0.000 588.46 0.000 588.46 0.000 588.46 0.000 588.46 0.000 588.46 0.000 588.46 0.000 588.46 0.000 588.46 0.000 588.46 0.000 588.46 0.000 588.46 0.000 588.46 0.000 588.46 0.000 588.46 0.000 588.46 0.000 588.46 0.000 588.46 0.000 588.45 0.000 588.45 0.000 588.45 0.000 588.45 0.000 588.45 0.000 588.45 0.000 588.45 0.000 588.45 Primary (cfs) 0.00 0.00 0.01 0.23 0.22 0.17 0.10 0.04 0.02 0.01 0.01 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 0.00 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 Printed 5/13/2024 Page 44

Post-Developed (O-1B) NJ DEP 2-hr WQ Rainfall=1.25", P2=3.42" West Orange HydroCAD_Post Printed 5/13/2024 Page 45 Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Summary for Pond 19P: SD-21 Inflow Area = 0.567 ac, 17.46% Impervious, Inflow Depth > 0.42" for WQ event Inflow = 0.12 cfs @ 1.80 hrs, Volume= 0.020 af Outflow = 0.12 cfs @ 1.80 hrs, Volume= 0.020 af, Atten= 0%, Lag= 0.1 min Primary = 0.12 cfs @ 1.80 hrs, Volume= 0.020 af Routed to Pond 18P : SD-22 Routing by Dyn-Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.0100 hrs Peak Elev= 590.78' @ 1.80 hrs Surf.Area= 0.000 ac Storage= 0.000 af Plug-Flow detention time= 0.0 min calculated for 0.020 af (100% of inflow) Center-of-Mass det. time= 0.0 min ( 151.7 - 151.6 ) Volume #1 Device #1 Invert 590.61' Avail.Storage 0.001 af Routing Primary Invert 590.61' Storage Description 12.0" Round SD-21 L= 64.5' S= 0.0150 '/' Outlet Devices 12.0" Vert. SD-21 C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.12 cfs @ 1.80 hrs HW=590.78' TW=588.69' (Dynamic Tailwater) 1=SD-21 (Orifice Controls 0.12 cfs @ 1.41 fps) Pond 19P: SD-21 Hydrograph Inflow Primary 0.12 cfs 0.13 Inflow Area=0.567 ac Peak Elev=590.78' Storage=0.000 af 0.12 cfs 0.12 0.11 0.1 Flow (cfs) 0.09 0.08 0.07 0.06 0.05 0.04 0.03 0.02 0.01 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-1B) NJ DEP 2-hr WQ Rainfall=1.25", P2=3.42" West Orange HydroCAD_Post Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Hydrograph for Pond 19P: SD-21 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 0.12 0.12 0.10 0.06 0.03 0.01 0.01 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 0.00 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 0.00 Storage Elevation (acre-feet) (feet) 0.000 590.61 0.000 590.61 0.000 590.63 0.000 590.77 0.000 590.78 0.000 590.76 0.000 590.73 0.000 590.69 0.000 590.66 0.000 590.65 0.000 590.64 0.000 590.64 0.000 590.63 0.000 590.63 0.000 590.63 0.000 590.62 0.000 590.62 0.000 590.62 0.000 590.62 0.000 590.62 0.000 590.62 0.000 590.62 0.000 590.62 0.000 590.62 0.000 590.62 0.000 590.62 0.000 590.62 0.000 590.62 0.000 590.62 0.000 590.62 0.000 590.62 0.000 590.62 0.000 590.62 0.000 590.61 0.000 590.61 0.000 590.61 0.000 590.61 0.000 590.61 0.000 590.61 0.000 590.61 0.000 590.61 0.000 590.61 0.000 590.61 0.000 590.61 0.000 590.61 0.000 590.61 0.000 590.61 0.000 590.61 0.000 590.61 Primary (cfs) 0.00 0.00 0.00 0.12 0.12 0.10 0.06 0.03 0.01 0.01 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 0.00 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 0.00 Printed 5/13/2024 Page 46

Post-Developed (O-1B) West Orange HydroCAD_Post NOAA 24-hr D 2-Year_Current Rainfall=3.45", 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 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 5S: PO-DA C Runoff Area=24,698 sf 17.46% Impervious Runoff Depth>2.14" Flow Length=164' Tc=18.5 min CN=WQ Runoff=0.93 cfs 0.101 af Subcatchment 7S: PO-DA E Runoff Area=15,246 sf 31.71% Impervious Runoff Depth>2.31" Flow Length=175' Tc=15.6 min CN=WQ Runoff=0.65 cfs 0.067 af Subcatchment 9S: PO-DA G Runoff Area=16,902 sf 28.87% Impervious Runoff Depth>2.26" Flow Length=175' Tc=23.3 min CN=WQ Runoff=0.59 cfs 0.073 af Subcatchment 11S: PO-DA I Runoff Area=10,507 sf 27.64% Impervious Runoff Depth>2.25" Flow Length=120' Tc=6.5 min CN=WQ Runoff=0.59 cfs 0.045 af Runoff Area=13,809 sf 38.48% Impervious Runoff Depth>2.35" Flow Length=96' Slope=0.0336 '/' Tc=5.4 min CN=WQ Runoff=0.83 cfs 0.062 af Subcatchment 12S: PO-DA J Pond 1P: BR-01 Peak Elev=598.20' Storage=1,470 cf Inflow=0.93 cfs 0.101 af Outflow=0.24 cfs 0.099 af Pond 2P: BR-02 Peak Elev=599.40' Storage=874 cf Inflow=0.65 cfs 0.067 af Outflow=0.19 cfs 0.066 af Pond 3P: BR-03 Peak Elev=595.19' Storage=1,059 cf Inflow=0.59 cfs 0.073 af Outflow=0.17 cfs 0.071 af Pond 5P: BR-05 Peak Elev=594.69' Storage=567 cf Inflow=0.59 cfs 0.045 af Outflow=0.15 cfs 0.044 af Pond 6P: BR-04 Peak Elev=595.53' Storage=970 cf Inflow=0.83 cfs 0.062 af Outflow=0.14 cfs 0.060 af Pond 8P: O-1B Inflow=0.87 cfs 0.341 af Primary=0.87 cfs 0.341 af Pond 13P: SD-25, SD-26 Peak Elev=580.86' Storage=0.000 af Inflow=0.87 cfs 0.341 af 18.0" Round Culvert n=0.011 L=29.4' S=0.0099 '/' Outflow=0.87 cfs 0.341 af Pond 14P: SD-24 Peak Elev=585.28' Storage=0.000 af Inflow=0.73 cfs 0.296 af Outflow=0.73 cfs 0.296 af Pond 17P: SD-23 Peak Elev=587.16' Storage=0.000 af Inflow=0.59 cfs 0.237 af Outflow=0.59 cfs 0.237 af Pond 18P: SD-22 Peak Elev=588.77' Storage=0.000 af Inflow=0.42 cfs 0.166 af Outflow=0.42 cfs 0.166 af Pond 19P: SD-21 Peak Elev=590.85' Storage=0.000 af Inflow=0.24 cfs 0.099 af Outflow=0.24 cfs 0.099 af

Post-Developed (O-1B) West Orange HydroCAD_Post NOAA 24-hr D 2-Year_Current Rainfall=3.45", P2=3.45" Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Printed 5/13/2024 Page 48 Total Runoff Area = 1.863 ac Runoff Volume = 0.349 af Average Runoff Depth = 2.25" 72.59% Pervious = 1.353 ac 27.41% Impervious = 0.511 ac

Post-Developed (O-1B) NOAA 24-hr D 2-Year_Current Rainfall=3.45", P2=3.45" West Orange HydroCAD_Post Printed 5/13/2024 Page 49 Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Summary for Subcatchment 5S: PO-DA C Runoff = 0.93 cfs @ 12.27 hrs, Volume= Routed to Pond 1P : BR-01 0.101 af, Depth> 2.14" 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 2-Year_Current Rainfall=3.45", P2=3.45" Area (sf) 4,312 2,396 17,990 24,698 20,386 4,312 * CN 98 80 85 Description Impervious, Pavement, HSG D >75% Grass cover, Good, HSG D Yard Stone/Gravel Pad, HSG D Weighted Average 82.54% Pervious Area 17.46% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 17.9 100 0.0018 0.09 Sheet Flow, Gravel Sheet Flow n= 0.100 P2= 3.45" 0.6 64 0.0106 1.66 Shallow Concentrated Flow, Shallow Concentrated Flow Unpaved Kv= 16.1 fps 18.5 164 Total Subcatchment 5S: PO-DA C Hydrograph Runoff 1 0.93 cfs Flow (cfs) NOAA 24-hr D 2-Year_Current Rainfall=3.45" P2=3.45" Runoff Area=24,698 sf Runoff Volume=0.101 af Runoff Depth>2.14" Flow Length=164' Tc=18.5 min CN=WQ 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-1B) West Orange HydroCAD_Post NOAA 24-hr D 2-Year_Current Rainfall=3.45", P2=3.45" Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Hydrograph for Subcatchment 5S: PO-DA C Time Precip. Excess (hours) (inches) (inches) 0.00 0.00 0.00 0.50 0.02 0.00 1.00 0.04 0.00 1.50 0.06 0.00 2.00 0.08 0.00 2.50 0.11 0.00 3.00 0.13 0.00 3.50 0.16 0.00 4.00 0.18 0.00 4.50 0.21 0.00 5.00 0.24 0.00 5.50 0.26 0.00 6.00 0.29 0.00 6.50 0.33 0.00 7.00 0.36 0.00 7.50 0.40 0.01 8.00 0.45 0.01 8.50 0.50 0.02 9.00 0.55 0.04 9.50 0.61 0.05 10.00 0.68 0.08 10.50 0.77 0.11 11.00 0.90 0.17 11.50 1.09 0.28 12.00 1.65 0.64 12.50 2.36 1.19 13.00 2.55 1.36 13.50 2.68 1.46 14.00 2.77 1.54 14.50 2.84 1.60 15.00 2.90 1.65 15.50 2.95 1.70 16.00 3.00 1.74 16.50 3.05 1.78 17.00 3.09 1.81 17.50 3.12 1.85 18.00 3.16 1.88 18.50 3.19 1.90 19.00 3.21 1.93 19.50 3.24 1.95 20.00 3.27 1.98 20.50 3.29 2.00 21.00 3.32 2.02 21.50 3.34 2.04 22.00 3.37 2.06 22.50 3.39 2.08 23.00 3.41 2.10 23.50 3.43 2.12 24.00 3.45 2.14 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 0.01 0.01 0.01 0.02 0.02 0.03 0.04 0.06 0.12 0.33 0.53 0.20 0.12 0.09 0.07 0.06 0.05 0.05 0.04 0.04 0.04 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.02 0.02 0.02 0.02 0.02 0.02 Printed 5/13/2024 Page 50

Post-Developed (O-1B) NOAA 24-hr D 2-Year_Current Rainfall=3.45", P2=3.45" West Orange HydroCAD_Post Printed 5/13/2024 Page 51 Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Summary for Subcatchment 7S: PO-DA E Runoff = 0.65 cfs @ 12.23 hrs, Volume= Routed to Pond 2P : BR-02 0.067 af, Depth> 2.31" 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_Current Rainfall=3.45", P2=3.45" Area (sf) 4,835 2,047 8,364 15,246 10,411 4,835 * CN 98 80 85 Description Impervious, Pavement, HSG D >75% Grass cover, Good, HSG D Yard Stone/Gravel Pad, HSG D Weighted Average 68.29% Pervious Area 31.71% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 14.6 100 0.0030 0.11 Sheet Flow, Gravel Sheet Flow n= 0.100 P2= 3.45" 1.0 75 0.0055 1.19 Shallow Concentrated Flow, Shallow Concentrated Flow Unpaved Kv= 16.1 fps 15.6 175 Total Subcatchment 7S: PO-DA E Hydrograph Runoff 0.7 0.65 cfs NOAA 24-hr D 2-Year_Current Rainfall=3.45" P2=3.45" Runoff Area=15,246 sf Runoff Volume=0.067 af Runoff Depth>2.31" Flow Length=175' Tc=15.6 min CN=WQ 0.65 0.6 0.55 0.5 Flow (cfs) 0.45 0.4 0.35 0.3 0.25 0.2 0.15 0.1 0.05 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