Town CrierWest Orange, New Jersey
← Back to search

Supporting Documentation · Jun 18, 2026

1240815StormWaterManagementReportrcd 3 12 2026

Preserved file SHA-2566db6651c28001b5f3edddede51757cf838a28dc31f6fb974ada19f161dfad9c8

Indexed text

Page 52

512-516 Pleasant Valley Way, West Orange 1240815-pipes3-C NOAA 24-hr D 25-Year-2020 Rainfall=6.72", P2=3.47" Prepared by Casey & Keller, Inc Printed 2/4/2026 HydroCAD® 10.20-7a s/n 03272 © 2025 HydroCAD Software Solutions LLC Summary for Pond 3: Pervious Pavers Inflow Area = 0.176 ac, 86.88% Impervious, Inflow Depth = 6.13" for 25-Year-2020 event Inflow = 1.20 cfs @ 12.06 hrs, Volume= 0.090 af Outflow = 0.41 cfs @ 12.18 hrs, Volume= 0.090 af, Atten= 66%, Lag= 7.0 min Discarded = 0.11 cfs @ 11.20 hrs, Volume= 0.078 af Primary = 0.30 cfs @ 12.18 hrs, Volume= 0.011 af Routed to Pond 5 : Pipes Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Peak Elev= 414.86' @ 12.18 hrs Surf.Area= 1,620 sf Storage= 879 cf Plug-Flow detention time= 34.7 min calculated for 0.090 af (100% of inflow) Center-of-Mass det. time= 34.6 min ( 781.7 - 747.0 ) Volume Invert Avail.Storage Storage Description #1 413.50' 1,730 cf 60.00'W x 27.00'L x 2.67'H STONE & PAVERS 4,325 cf Overall x 40.0% Voids Device Routing Invert Outlet Devices #1 Discarded 413.50' 2.900 in/hr Exfiltration over Surface area #2 Primary 414.50' 6.0" Round Culvert L= 50.0' Ke= 0.200 Inlet / Outlet Invert= 414.50' / 414.17' S= 0.0066 '/' Cc= 0.900 n= 0.010 PVC, smooth interior, Flow Area= 0.20 sf Discarded OutFlow Max=0.11 cfs @ 11.20 hrs HW=413.53' (Free Discharge) 1=Exfiltration (Exfiltration Controls 0.11 cfs) Primary OutFlow Max=0.30 cfs @ 12.18 hrs HW=414.86' (Free Discharge) 2=Culvert (Barrel Controls 0.30 cfs @ 2.81 fps) 49

Page 53

512-516 Pleasant Valley Way, West Orange 1240815-pipes3-C NOAA 24-hr D 25-Year-2020 Rainfall=6.72", P2=3.47" Prepared by Casey & Keller, Inc Printed 2/4/2026 HydroCAD® 10.20-7a s/n 03272 © 2025 HydroCAD Software Solutions LLC Pond 3: Pervious Pavers Hydrograph 1.20 cfs Inflow Outflow Inflow Area=0.176 ac Discarded Primary Peak Elev=414.86' Storage=879 cf 1 Flow (cfs) 0.41 cfs 0.30 cfs 0.11 cfs 0 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) 50

Page 54

512-516 Pleasant Valley Way, West Orange 1240815-pipes3-C NOAA 24-hr D 25-Year-2020 Rainfall=6.72", P2=3.47" Prepared by Casey & Keller, Inc Printed 2/4/2026 HydroCAD® 10.20-7a s/n 03272 © 2025 HydroCAD Software Solutions LLC Summary for Pond 5: Pipes Inflow Area = 0.343 ac, 76.01% Impervious, Inflow Depth = 3.09" for 25-Year-2020 event Inflow = 1.11 cfs @ 12.08 hrs, Volume= 0.088 af Outflow = 0.99 cfs @ 12.11 hrs, Volume= 0.088 af, Atten= 11%, Lag= 1.9 min Discarded = 0.03 cfs @ 9.25 hrs, Volume= 0.037 af Primary = 0.96 cfs @ 12.11 hrs, Volume= 0.052 af Routed to Link 7 : Proposed Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Peak Elev= 411.66' @ 12.11 hrs Surf.Area= 400 sf Storage= 245 cf Plug-Flow detention time= 13.6 min calculated for 0.088 af (100% of inflow) Center-of-Mass det. time= 13.6 min ( 772.9 - 759.3 ) Volume Invert Avail.Storage Storage Description #1 410.50' 329 cf 10.00'W x 40.00'L x 3.00'H STONE 1,200 cf Overall - 377 cf Embedded = 823 cf x 40.0% Voids #2 411.00' 377 cf 24.0" Round Pipe Storage x 3 Inside #1 L= 40.0' S= 0.0020 '/' 706 cf Total Available Storage Device Routing Invert Outlet Devices #1 Discarded 410.50' 2.900 in/hr Exfiltration over Surface area #2 Primary 411.00' 12.0" Round Culvert L= 14.0' Ke= 0.100 Inlet / Outlet Invert= 411.00' / 410.94' S= 0.0043 '/' Cc= 0.900 n= 0.012 Corrugated PP, smooth interior, Flow Area= 0.79 sf #3 Device 2 411.00' 8.0" Vert. Orifice C= 0.600 Limited to weir flow at low heads #4 Device 2 413.90' 24.0" x 24.0" Horiz. Grate C= 0.600 Limited to weir flow at low heads Discarded OutFlow Max=0.03 cfs @ 9.25 hrs HW=410.53' (Free Discharge) 1=Exfiltration (Exfiltration Controls 0.03 cfs) Primary OutFlow Max=0.95 cfs @ 12.11 hrs HW=411.65' (Free Discharge) 2=Culvert (Passes 0.95 cfs of 1.17 cfs potential flow)

Page 54

(Free Discharge) 1=Exfiltration (Exfiltration Controls 0.03 cfs) Primary OutFlow Max=0.95 cfs @ 12.11 hrs HW=411.65' (Free Discharge) 2=Culvert (Passes 0.95 cfs of 1.17 cfs potential flow) 3=Orifice (Orifice Controls 0.95 cfs @ 2.74 fps) 4=Grate ( Controls 0.00 cfs) 51

Page 55

512-516 Pleasant Valley Way, West Orange 1240815-pipes3-C NOAA 24-hr D 25-Year-2020 Rainfall=6.72", P2=3.47" Prepared by Casey & Keller, Inc Printed 2/4/2026 HydroCAD® 10.20-7a s/n 03272 © 2025 HydroCAD Software Solutions LLC Pond 5: Pipes Hydrograph 1.11 cfs Inflow Outflow Inflow Area=0.343 ac Discarded Primary 0.99 cfs Peak Elev=411.66' 0.96 cfs 1 Storage=245 cf Flow (cfs) 0.03 cfs 0 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) 52

Page 56

512-516 Pleasant Valley Way, West Orange 1240815-pipes3-C NOAA 24-hr D 25-Year-2020 Rainfall=6.72", P2=3.47" Prepared by Casey & Keller, Inc Printed 2/4/2026 HydroCAD® 10.20-7a s/n 03272 © 2025 HydroCAD Software Solutions LLC Summary for Link 7: Proposed Inflow Area = 0.373 ac, 69.84% Impervious, Inflow Depth = 1.97" for 25-Year-2020 event Inflow = 1.09 cfs @ 12.11 hrs, Volume= 0.061 af Primary = 1.09 cfs @ 12.11 hrs, Volume= 0.061 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Link 7: Proposed Hydrograph Inflow 1.09 cfs Primary 1.09 cfs Inflow Area=0.373 ac 1 Flow (cfs) 0 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) 53

Page 57

512-516 Pleasant Valley Way, West Orange 1240815-pipes3-C NOAA 24-hr D 100-Year-2020 Rainfall=9.18", P2=3.47" Prepared by Casey & Keller, Inc Printed 2/4/2026 HydroCAD® 10.20-7a s/n 03272 © 2025 HydroCAD Software Solutions LLC Time span=0.00-72.00 hrs, dt=0.05 hrs, 1441 points Runoff by SCS TR-20 method, UH=SCS, Split Pervious/Imperv. UI as Pervious Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment 1: Exisiting Runoff Area=16,242 sf 67.90% Impervious Runoff Depth=7.99" Flow Length=141' Tc=5.9 min CN=74/98 Runoff=2.96 cfs 0.248 af Subcatchment 2: Parking Lot Runoff Area=7,658 sf 86.88% Impervious Runoff Depth=8.55" Flow Length=92' Tc=1.0 min CN=74/98 Runoff=1.66 cfs 0.125 af Subcatchment 4: Proposed Runoff Area=7,266 sf 64.56% Impervious Runoff Depth=7.90" Flow Length=92' Tc=1.0 min CN=74/98 Runoff=1.49 cfs 0.110 af Subcatchment 6: Bypass Runoff Area=1,318 sf 0.00% Impervious Runoff Depth=5.99" Flow Length=128' Tc=6.0 min CN=74/0 Runoff=0.20 cfs 0.015 af Pond 3: Pervious Pavers Peak Elev=415.32' Storage=1,177 cf Inflow=1.66 cfs 0.125 af Discarded=0.11 cfs 0.096 af Primary=0.67 cfs 0.029 af Outflow=0.78 cfs 0.125 af Pond 5: Pipes Peak Elev=412.24' Storage=420 cf Inflow=2.07 cfs 0.139 af Discarded=0.03 cfs 0.044 af Primary=1.60 cfs 0.096 af Outflow=1.63 cfs 0.139 af Link 7: Proposed Inflow=1.80 cfs 0.111 af Primary=1.80 cfs 0.111 af Total Runoff Area = 0.746 ac Runoff Volume = 0.499 af Average Runoff Depth = 8.02" 31.13% Pervious = 0.232 ac 68.87% Impervious = 0.514 ac 54

Page 58

512-516 Pleasant Valley Way, West Orange 1240815-pipes3-C NOAA 24-hr D 100-Year-2020 Rainfall=9.18", P2=3.47" Prepared by Casey & Keller, Inc Printed 2/4/2026 HydroCAD® 10.20-7a s/n 03272 © 2025 HydroCAD Software Solutions LLC Summary for Subcatchment 1: Exisiting Runoff = 2.96 cfs @ 12.13 hrs, Volume= 0.248 af, Depth= 7.99" Runoff by SCS TR-20 method, UH=SCS, Split Pervious/Imperv. UI as Pervious, Time Span= 0.00-72.00 hrs, dt= 0.05 NOAA 24-hr D 100-Year-2020 Rainfall=9.18", P2=3.47" Area (sf) CN Description * 2,708 98 Buildings * 758 98 Walks/Steps & Patio 7,562 98 Paved parking, HSG C 5,214 74 >75% Grass cover, Good, HSG C 16,242 90 Weighted Average 5,214 74 32.10% Pervious Area 11,028 98 67.90% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 4.1 66 0.0680 0.27 Sheet Flow, 1 Grass: Short n= 0.150 P2= 3.47" 1.4 21 0.0950 0.24 Sheet Flow, 2 Grass: Short n= 0.150 P2= 3.47" 0.2 13 0.0390 1.24 Sheet Flow, 3 Smooth surfaces n= 0.011 P2= 3.47" 0.1 13 0.0390 4.01 Shallow Concentrated Flow, 4 Paved Kv= 20.3 fps 0.1 28 0.0360 3.85 Shallow Concentrated Flow, 5 Paved Kv= 20.3 fps 5.9 141 Total 55

Page 59

512-516 Pleasant Valley Way, West Orange 1240815-pipes3-C NOAA 24-hr D 100-Year-2020 Rainfall=9.18", P2=3.47" Prepared by Casey & Keller, Inc Printed 2/4/2026 HydroCAD® 10.20-7a s/n 03272 © 2025 HydroCAD Software Solutions LLC Subcatchment 1: Exisiting Hydrograph Runoff 2.96 cfs 3 NOAA 24-hr D 100-Year-2020 Rainfall=9.18" P2=3.47" Runoff Area=16,242 sf 2 Runoff Volume=0.248 af Flow (cfs) Runoff Depth=7.99" Flow Length=141' Tc=5.9 min 1 CN=74/98 0 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) 56

Page 60

512-516 Pleasant Valley Way, West Orange 1240815-pipes3-C NOAA 24-hr D 100-Year-2020 Rainfall=9.18", P2=3.47" Prepared by Casey & Keller, Inc Printed 2/4/2026 HydroCAD® 10.20-7a s/n 03272 © 2025 HydroCAD Software Solutions LLC Summary for Subcatchment 2: Parking Lot Runoff = 1.66 cfs @ 12.06 hrs, Volume= 0.125 af, Depth= 8.55" Routed to Pond 3 : Pervious Pavers Runoff by SCS TR-20 method, UH=SCS, Split Pervious/Imperv. UI as Pervious, Time Span= 0.00-72.00 hrs, dt= 0.05 NOAA 24-hr D 100-Year-2020 Rainfall=9.18", P2=3.47" Area (sf) CN Description * 6,578 98 PARKING LOT 1,005 74 >75% Grass cover, Good, HSG C * 75 98 REFUSE AREA 7,658 95 Weighted Average 1,005 74 13.12% Pervious Area 6,653 98 86.88% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 0.1 8 0.0650 1.38 Sheet Flow, 1 Smooth surfaces n= 0.011 P2= 3.47" 0.2 15 0.0670 1.59 Sheet Flow, 2 Smooth surfaces n= 0.011 P2= 3.47" 0.5 59 0.0500 1.86 Sheet Flow, 3 Smooth surfaces n= 0.011 P2= 3.47" 0.2 10 0.0250 0.99 Sheet Flow, 4 Smooth surfaces n= 0.011 P2= 3.47" 1.0 92 Total 57

File revisions (1)