J_2024 05 09_West Orange Stormwater Management Plan

Post-Developed (25-Year) NOAA 24-hr D 25-Year Rainfall=6.44", P2=3.42" West Orange HydroCAD_Post Printed 5/13/2024 Page 54 Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Summary for Pond 7P: O-1A Inflow Area = Inflow = Primary = 1.409 ac, 2.20% Impervious, Inflow Depth > 3.61" for 25-Year event 4.68 cfs @ 12.19 hrs, Volume= 0.424 af 4.68 cfs @ 12.19 hrs, Volume= 0.424 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 7P: O-1A Hydrograph Inflow Primary 4.68 cfs 5 Inflow Area=1.409 ac 4.68 cfs Flow (cfs) 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 (25-Year) West Orange HydroCAD_Post NOAA 24-hr D 25-Year Rainfall=6.44", P2=3.42" Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Hydrograph for Pond 7P: O-1A 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 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.01 0.01 0.02 0.03 0.07 0.11 0.15 0.26 0.51 1.92 1.67 0.78 0.50 0.37 0.32 0.26 0.23 0.21 0.19 0.18 0.16 0.14 0.13 0.13 0.12 0.12 0.12 0.11 0.11 0.10 0.10 0.10 0.09 0.09 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 0.01 0.01 0.02 0.03 0.07 0.11 0.15 0.26 0.51 1.92 1.67 0.78 0.50 0.37 0.32 0.26 0.23 0.21 0.19 0.18 0.16 0.14 0.13 0.13 0.12 0.12 0.12 0.11 0.11 0.10 0.10 0.10 0.09 0.09 Printed 5/13/2024 Page 55

Post-Developed (25-Year) NOAA 24-hr D 25-Year Rainfall=6.44", P2=3.42" West Orange HydroCAD_Post Printed 5/13/2024 Page 56 Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Summary for Pond 8P: O-1B Inflow Area = Inflow = Primary = 1.863 ac, 27.41% Impervious, Inflow Depth > 4.95" for 25-Year event 1.83 cfs @ 12.46 hrs, Volume= 0.768 af 1.83 cfs @ 12.46 hrs, Volume= 0.768 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 8P: O-1B Hydrograph 2 Inflow Primary 1.83 cfs Inflow Area=1.863 ac Flow (cfs) 1.83 cfs 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 (25-Year) West Orange HydroCAD_Post NOAA 24-hr D 25-Year Rainfall=6.44", P2=3.42" Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Hydrograph for Pond 8P: O-1B 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 0.02 0.02 0.03 0.04 0.05 0.06 0.07 0.08 0.10 0.12 0.15 0.17 0.20 0.25 0.30 0.38 0.51 0.79 1.82 1.53 1.37 1.27 1.16 1.05 0.96 0.87 0.77 0.66 0.58 0.50 0.43 0.37 0.32 0.28 0.25 0.22 0.19 0.18 0.17 0.16 0.15 0.14 Primary (cfs) 0.00 0.00 0.00 0.00 0.00 0.01 0.01 0.02 0.02 0.03 0.04 0.05 0.06 0.07 0.08 0.10 0.12 0.15 0.17 0.20 0.25 0.30 0.38 0.51 0.79 1.82 1.53 1.37 1.27 1.16 1.05 0.96 0.87 0.77 0.66 0.58 0.50 0.43 0.37 0.32 0.28 0.25 0.22 0.19 0.18 0.17 0.16 0.15 0.14 Printed 5/13/2024 Page 57

Post-Developed (25-Year) NOAA 24-hr D 25-Year Rainfall=6.44", P2=3.42" 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 58 Summary for Pond 12P: SD-03, SD-04, SD-05 Inflow Area = 0.803 ac, 0.00% Impervious, Inflow Depth > 3.55" for 25-Year event Inflow = 2.59 cfs @ 12.19 hrs, Volume= 0.238 af Outflow = 2.58 cfs @ 12.20 hrs, Volume= 0.238 af, Atten= 0%, Lag= 0.2 min Primary = 2.58 cfs @ 12.20 hrs, Volume= 0.238 af Routed to Pond 15P : SD-06, SD-07, SD-08 Routing by Dyn-Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.0100 hrs Peak Elev= 596.71' @ 12.20 hrs Surf.Area= 85 sf Storage= 41 cf Plug-Flow detention time= 0.6 min calculated for 0.238 af (100% of inflow) Center-of-Mass det. time= 0.4 min ( 840.5 - 840.1 ) Volume #1 Invert 603.40' Avail.Storage 8 cf #2 #3 596.79' 596.56' 79 cf 16 cf #4 #5 596.31' 595.95' 86 cf 64 cf #6 595.71' 93 cf 346 cf Storage Description 12.0" Round SD-03 L= 10.0' S= 0.0100 '/' MH-02 (Prismatic) Listed below (Recalc) 12.0" Round SD-04 L= 20.0' S= 0.0100 '/' MH-03 (Prismatic) Listed below (Recalc) 18.0" Round SD-05 L= 36.0' S= 0.0100 '/' MH-04 (Prismatic) Listed below (Recalc) Total Available Storage Elevation (feet) 596.79 602.90 Surf.Area (sq-ft) 13 13 Inc.Store (cubic-feet) 0 79 Cum.Store (cubic-feet) 0 79 Elevation (feet) 596.31 602.90 Surf.Area (sq-ft) 13 13 Inc.Store (cubic-feet) 0 86 Cum.Store (cubic-feet) 0 86 Elevation (feet) 595.71 602.90 Surf.Area (sq-ft) 13 13 Inc.Store (cubic-feet) 0 93 Cum.Store (cubic-feet) 0 93 Device #1 Routing Primary Invert 595.96' Outlet Devices 18.0" Vert. SD-05 C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=2.58 cfs @ 12.20 hrs HW=596.71' TW=594.72' (Dynamic Tailwater) 1=SD-05 (Orifice Controls 2.58 cfs @ 2.94 fps)

Post-Developed (25-Year) NOAA 24-hr D 25-Year Rainfall=6.44", P2=3.42" West Orange HydroCAD_Post Printed 5/13/2024 Page 59 Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Pond 12P: SD-03, SD-04, SD-05 Hydrograph Inflow Primary 2.59 cfs Inflow Area=0.803 ac Peak Elev=596.71' Storage=41 cf 2.58 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 (25-Year) West Orange HydroCAD_Post NOAA 24-hr D 25-Year Rainfall=6.44", P2=3.42" Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Hydrograph for Pond 12P: SD-03, SD-04, SD-05 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 0.00 0.00 0.01 0.04 0.06 0.08 0.14 0.28 1.07 0.96 0.44 0.29 0.21 0.18 0.15 0.13 0.12 0.11 0.10 0.09 0.08 0.08 0.07 0.07 0.07 0.07 0.06 0.06 0.06 0.06 0.05 0.05 0.05 Storage Elevation (cubic-feet) (feet) 0 595.71 0 595.71 0 595.71 0 595.71 0 595.71 0 595.71 0 595.71 0 595.71 0 595.71 0 595.71 0 595.71 0 595.71 0 595.72 1 595.79 3 595.94 4 595.98 4 595.98 4 595.99 4 595.99 5 596.04 5 596.06 5 596.08 6 596.12 8 596.19 19 596.42 18 596.40 10 596.25 8 596.19 7 596.16 7 596.14 6 596.13 6 596.11 6 596.11 6 596.10 6 596.10 5 596.09 5 596.08 5 596.08 5 596.08 5 596.07 5 596.07 5 596.07 5 596.07 5 596.07 5 596.06 5 596.06 5 596.06 5 596.06 5 596.06 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 0.01 0.04 0.06 0.08 0.14 0.28 1.05 0.97 0.44 0.29 0.21 0.18 0.15 0.13 0.12 0.11 0.10 0.09 0.08 0.08 0.07 0.07 0.07 0.07 0.06 0.06 0.06 0.06 0.05 0.05 0.05 Printed 5/13/2024 Page 60

Post-Developed (25-Year) West Orange HydroCAD_Post NOAA 24-hr D 25-Year Rainfall=6.44", P2=3.42" Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Printed 5/13/2024 Page 61 Summary for Pond 13P: SD-25, SD-26 Inflow Area = 1.863 ac, 27.41% Impervious, Inflow Depth > 4.95" for 25-Year event Inflow = 1.83 cfs @ 12.46 hrs, Volume= 0.768 af Outflow = 1.83 cfs @ 12.46 hrs, Volume= 0.768 af, Atten= 0%, Lag= 0.1 min Primary = 1.83 cfs @ 12.46 hrs, Volume= 0.768 af Routed to Pond 8P : O-1B Routing by Dyn-Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.0100 hrs Peak Elev= 581.08' @ 12.46 hrs Surf.Area= 0.001 ac Storage= 0.000 af Plug-Flow detention time= (not calculated: outflow precedes inflow) Center-of-Mass det. time= 0.0 min ( 881.5 - 881.5 ) Volume #1 Device #1 Invert 580.69' Routing Primary Avail.Storage 0.007 af Invert 580.44' Storage Description 15.0" Round SD-25 L= 262.4' S= 0.0150 '/' Outlet Devices 18.0" Round SD-26 L= 29.4' RCP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 580.44' / 580.15' S= 0.0099 '/' Cc= 0.900 n= 0.011 Concrete pipe, straight & clean, Flow Area= 1.77 sf Primary OutFlow Max=1.83 cfs @ 12.46 hrs HW=581.08' TW=0.00' (Dynamic Tailwater) 1=SD-26 (Barrel Controls 1.83 cfs @ 3.73 fps)

Post-Developed (25-Year) NOAA 24-hr D 25-Year Rainfall=6.44", P2=3.42" West Orange HydroCAD_Post Printed 5/13/2024 Page 62 Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Pond 13P: SD-25, SD-26 Hydrograph Flow (cfs) 2 Inflow Primary 1.83 cfs Inflow Area=1.863 ac Peak Elev=581.08' Storage=0.000 af 18.0" Round Culvert n=0.011 L=29.4' S=0.0099 '/' 1 1.83 cfs 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 (25-Year) West Orange HydroCAD_Post NOAA 24-hr D 25-Year Rainfall=6.44", P2=3.42" Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Hydrograph for Pond 13P: SD-25, SD-26 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 0.01 0.01 0.02 0.02 0.03 0.04 0.05 0.06 0.07 0.08 0.10 0.12 0.15 0.17 0.20 0.25 0.31 0.38 0.51 0.79 1.82 1.53 1.37 1.27 1.16 1.05 0.96 0.87 0.77 0.66 0.58 0.50 0.43 0.37 0.32 0.28 0.25 0.22 0.19 0.18 0.17 0.16 0.15 0.14 Storage Elevation (acre-feet) (feet) 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.71 0.000 580.75 0.000 580.84 0.000 581.08 0.000 581.02 0.000 580.98 0.000 580.96 0.000 580.93 0.000 580.91 0.000 580.88 0.000 580.86 0.000 580.83 0.000 580.80 0.000 580.78 0.000 580.75 0.000 580.73 0.000 580.71 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 0.000 580.69 Primary (cfs) 0.00 0.00 0.00 0.00 0.00 0.01 0.01 0.02 0.02 0.03 0.04 0.05 0.06 0.07 0.08 0.10 0.12 0.15 0.17 0.20 0.25 0.30 0.38 0.51 0.79 1.82 1.53 1.37 1.27 1.16 1.05 0.96 0.87 0.77 0.66 0.58 0.50 0.43 0.37 0.32 0.28 0.25 0.22 0.19 0.18 0.17 0.16 0.15 0.14 Printed 5/13/2024 Page 63