Stormwater Report

512-516 Pleasant Valley Way, West Orange 1240815-pipes NOAA 24-hr D 10-Year-2020 Rainfall=5.38", P2=3.47" Prepared by Casey & Keller, Inc Printed 8/25/2025 HydroCAD® 10.20-7a_s/n 03272 © 2025 HydroCAD Software Solutions LLC Page 22 Summary for Subcatchment 4: Proposed Runoff = 0.91 cfs@ 12.06 hrs, Volume= 0.065 af, Depth= 4.06" Routed to Pond 5 : Pipes 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 10-Year-2020 Rainfall=5.38", P2=3.47" Area (sf) CN Description 3,522 98 Roofs, HSG C 1,136 98 Paved parking, HSG C 3,674 74 >75% Grass cover, Good, HSG C * 60___98 _Areaway 8,392 87 Weighted Average 3,674 74 43.78% Pervious Area 4,718 98 56.22% 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" 0.1 15 0.6700 3.99 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" 0.9 92 Total 29

512-516 Pleasant Valley Way, West Orange 1240815-pipes NOAA 24-hr D 10-Year-2020 Rainfall=5.38", P2=3.47" Prepared by Casey & Keller, Inc Printed 8/25/2025 HydroCAD® 10.20-7a_s/n 03272 © 2025 HydroCAD Software Solutions LLC Page 23 Subcatchment 4: Proposed Hydrograph NOAA 24-hr D 10-Year-2020 Rainfall=5.38" P2=3.47" Runoff Area=8,392 sf Runoff Volume=0.065 af Runoff Depth=4.06" Flow Length=92' Tc=0.9 min CN=74/98 Flow (cfs) o4 : aa ; 4 a ; . 0 2 4 & B 10 1214 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) 30

512-516 Pleasant Valley Way, West Orange 1240815-pipes NOAA 24-hr D 10-Year-2020 Rainfall=5.38", P2=3.47" Prepared by Casey & Keller, Inc Printed 8/25/2025 HydroCAD® 10.20-7a_s/n 03272 © 2025 HydroCAD Software Solutions LLC Page 24 Summary for Pond 5: Pipes Inflow Area = 0.360 ac, 72.63% Impervious, Inflow Depth= 2.24" for 10-Year-2020 event Inflow = 0.91 cfs@ 12.06 hrs, Volume= 0.067 af Outflow = 0.69 cfs @ 12.11 hrs, Volume= 0.067 af, Atten= 24%, Lag= 2.8 min Discarded = 0.03 cfs@ 9.75hrs, Volume= 0.033 af Primary = 0.66 cfs @ 12.11 hrs, Volume= 0.034 af Routed to Link 7 : Proposed Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Peak Elev= 412.74' @ 12.11 hrs Surf.Area= 400 sf Storage= 268 cf Plug-Flow detention time= 15.3 min calculated for 0.067 af (100% of inflow) Center-of-Mass det. time= 15.3 min ( 785.8 - 770.4 ) Volume Invert Avail.Storage Storage Description #1 411.50° 329 cf 10.00'W x 40.00'L x 3.00'H Prismatoid 1,200 cf Overall - 377 cf Embedded = 823 cf x 40.0% Voids #2 412.00° 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 411.50' 2.900 in/hr Exfiltration over Surface area #2 ~~~ Primary 412.00' 12.0" Round Culvert L=14.0' Ke= 0.100 Inlet / Outlet Invert= 412.00'/ 411.94" S= 0.0043 '" Cc= 0.900 n= 0.012 Corrugated PP, smooth interior, Flow Area= 0.79 sf #3 =~ Device 2 412.00’ 6.0" Vert. Orifice C= 0.600 Limited to weir flow at low heads #4 ~=Device 2 414.00’ 24.0" x 24.0" Horiz. Grate C= 0.600 Limited to weir flow at low heads liscarded OutFlow Max=0.03 cfs @ 9.75 hrs HW=411.53' (Free Discharge) 41=Exfiltration (Exfiltration Controls 0.03 cfs) Primary OutFlow Max=0.65 cfs @ 12.11 hrs HW=412.72' (Free Discharge) Fs-oni (Passes 0.65 cfs of 1.43 cfs potential flow) Orifice (Orifice Controls 0.65 cfs @ 3.32 fps) =Grate ( Controls 0.00 cfs) 31

1240815-pipes Prepared by Casey & Keller, Inc 512-516 Pleasant Valley Way, West Orange NOAA 24-hr D 10-Year-2020 Rainfall=5.38", P2=3.47" Printed 8/25/2025 HydroCAD® 10.20-7a_s/n 03272 © 2025 HydroCAD Software Solutions LLC Page 25 Pond 5: Pipes Hydrograph i Infiow © Outiow a Inflow Area=0.360 ac | [BBs Peak Elev=412.74' Flow (cfs) Storage=268 cf LE” 0 , aps y 0 2 4 6 & 10121416 18 20 22 24 26 28 30 32 34 3638 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) 32

512-516 Pleasant Valley Way, West Orange 1240815-pipes NOAA 24-hr D 10-Year-2020 Rainfall=5.38", P2=3.47" Prepared by Casey & Keller, Inc Printed 8/25/2025 HydroCAD® 10.20-7a_s/n 03272 © 2025 HydroCAD Software Solutions LLC Page 26 Summary for Subcatchment 6: Bypass Runoff = 0.04 cfs@ 12.13 hrs, Volume= 0.003 af, Depth= 2.67" Routed to Link 7 : Proposed 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 10-Year-2020 Rainfall=5.38", P2=3.47" Area (sf) CN Description 605__ 74 ~~>75% Grass cover, Good, HSG C 605 74 100.00% Pervious Area Te Length Slope Velocity Capacity Description (min) (feet) (ft/ft)__ (ft/sec) (cfs) 5.9 100 0.0650 0.28 Sheet Flow, 1 Grass: Short n= 0.150 P2= 3.47" 0.1 28 0.0900 4.50 Shallow Concentrated Flow, 2 Grassed Waterway Kv= 15.0 fps 6.0 128 Total Subcatchment 6: Bypass Hydrograph NOAA 24-hr D 10-Year-2020 Rainfall=5.38" P2=3.47" Runoff Area=605 sf Runoff Volume=0.003 af Runoff Depth=2.67" Flow Length=128' Tc=6.0 min CN=74/0 Flow (cfs) ° 8 . Time (hours) 33

512-516 Pleasant Valley Way, West Orange 1240815-pipes NOAA 24-hr D 10-Year-2020 Rainfall=5.38", P2=3.47" Prepared by Casey & Keller, Inc Printed 8/25/2025 HydroCAD® 10.20-7a_s/n 03272 © 2025 HydroCAD Software Solutions LLC Page 27 Summary for Link 7: Proposed Inflow Area = 0.374 ac, 69.93% Impervious, Inflow Depth= 1.19" for 10-Year-2020 event Inflow = 0.70 cfs@ 12.11 hrs, Volume= 0.037 af Primary) = 0.70 cfs @ 12.11 hrs, Volume= 0.037 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 Binflow Primary on Inflow Area=0.374 ac 0 2 4 6 B 101214 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 6062 64 66 68 70 72 Time (hours) 34

512-516 Pleasant Valley Way, West Orange 1240815-pipes NOAA 24-hr D 100-Year-2020 Rainfall=9. 18", P2=3.47" Prepared by Casey & Keller, Inc Printed 8/25/2025 HydroCAD® 10.20-7a_s/n 03272 © 2025 HydroCAD Software Solutions LLC Page 28 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 Subcatchment1: Exisiting Runoff Area=16,242 sf 68.64% Impervious Runoff Depth=8.02" Flow Length=141' Tc=5.9 min CN=74/98 Runoff=2.97 cfs 0.249 af Subcatchment2: Parking Lot Runoff Area=7,305 sf 91.47% Impervious Runoff Depth=8.69" Flow Length=92' Tc=0.9 min CN=74/98 Runoff=1.59 cfs 0.121 af Pond 3: Pervious Pavers Peak Elev=415.26' Storage=1,140 cf Inflow= Discarded=0.11 cfs 0.094 af Primary=0.64 cfs 0.027 af Outflow= 1.59 cfs 0.121 af .75 cfs 0.121 af Subcatchment4: Proposed Runoff Area=8,392 sf 56.22% Impervious Runoff Depth=7.65" Flow Length=92' Tc=0.9 min CN=74/98 Runoff=1.69 cfs 0.123 af Pond 5: Pipes Peak Elev=414.09' Storage=641 cf Inflow=2.21 cfs 0.150 af Discarded=0.03 cfs 0.045 af Primary=1.83 cfs 0.105 af Outflow=1.86 cfs 0.150 af Subcatchment6: Bypass Runoff Area=605 sf 0.00% Impervious Runoff Depth=5.99" Flow Length=128' Tc=6.0 min CN=74/0 Runoff=0.09 cfs 0.007 af Link 7: Proposed Inflow=1.92 cfs 0.112 af Primary=1.92 cfs 0.112 af Total Runoff Area = 0.747 ac Runoff Volume = 0.500 af Average Runoff Depth = 8.03" 30.71% Pervious = 0.229 ac 69.29% Impervious = 0.518 ac 35

512-516 Pleasant Valley Way, West Orange 1240815-pipes NOAA 24-hr D 100-Year-2020 Rainfall=9.18", P2=3.47" Prepared by Casey & Keller, Inc Printed 8/25/2025 HydroCAD® 10.20-7a_s/n 03272 © 2025 HydroCAD Software Solutions LLC Page 29 Summary for Subcatchment 1: Exisiting Runoff = 2.97 cfs @ 12.13 hrs, Volume= 0.249 af, Depth= 8.02" 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 2,676 98 Buildings id 794 98 Walks/Steps & Patio 7,679 98 Paved parking, HSG C 5,093 74 _>75% Grass cover, Good, HSG C 16,242 90 Weighted Average 5,093 74 31.36% Pervious Area 11,149 98 68.64% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (fU/ft) (ft/sec) (cfs) 44 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 36

512-516 Pleasant Valley Way, West Orange 1240815-pipes NOAA 24-hr D 100-Year-2020 Rainfall=9. 18", P2=3.47" Prepared by Casey & Keller, Inc Printed 8/25/2025 HydroCAD® 10.20-7a_s/n 03272 © 2025 HydroCAD Software Solutions LLC Page 30 Subcatchment 1: Exisiting Hydrograph NOAA 24-hr D 100-Year-2020 Rainfall=9.18" P2=3.47" Runoff Area=16,242 sf Runoff Volume=0.249 af Runoff Depth=8.02" Flow Length=141' Tc=5.9 min CN=74/98 Flow (cfs) 0-4 Leap apt) y wap 0 2 4 6 8 10 1214 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) 37

512-516 Pleasant Valley Way, West Orange 1240815-pipes NOAA 24-hr D 100-Year-2020 Rainfall=9. 18", P2=3.47" Prepared by Casey & Keller, Inc Printed 8/25/2025 HydroCAD® 10.20-7a_s/n 03272 © 2025 HydroCAD Software Solutions LLC Page 31 Summary for Subcatchment 2: Parking Lot Runoff = 1.59 cfs @ 12.06 hrs, Volume= 0.121 af, Depth= 8.69" 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 6,682 98 Paved parking, HSG C 623 74 _>75% Grass cover, Good, HSG C 7,305 96 Weighted Average 623 74 8.53% Pervious Area 6,682 98 91.47% Impervious Area Te 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" 0.1 15 0.6700 3.99 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" 0.9 92 Total 38