Supporting Documentation · Jan 7, 2026
09 Stormwater Mgmt Report 122025
671005d8c0aeaab7a16315eaa245a42512090a6bf622a657aa6b07da423c2420Indexed text
NJA230139 - REV 2 Prepared by Bohler Engineering, PC HydroCAD® 10.20-7a s/n 03478 © 2025 HydroCAD Software Solutions LLC Area Listing (all nodes) Area (sq-ft) CN Description (subcatchment-numbers) 4,792 165,528 170,320 39 98 96 >75% Grass cover, Good, HSG A (E1p, P1p) Paved parking, HSG A (E1i, P1i, P1i(pp)) TOTAL AREA Printed 12/11/2025 Page 3
NJA230139 - REV 2 Prepared by Bohler Engineering, PC HydroCAD® 10.20-7a s/n 03478 © 2025 HydroCAD Software Solutions LLC Soil Listing (all nodes) Area (sq-ft) Soil Group Subcatchment Numbers 170,320 0 0 0 0 170,320 HSG A HSG B HSG C HSG D Other E1i, E1p, P1i, P1i(pp), P1p TOTAL AREA Printed 12/11/2025 Page 4
NJA230139 - REV 2 Printed 12/11/2025 Page 5 Prepared by Bohler Engineering, PC HydroCAD® 10.20-7a s/n 03478 © 2025 HydroCAD Software Solutions LLC Ground Covers (all nodes) HSG-A (sq-ft) HSG-B (sq-ft) HSG-C (sq-ft) HSG-D (sq-ft) Other (sq-ft) Total (sq-ft) Ground Cover 4,792 0 0 0 0 4,792 165,528 170,320 0 0 0 0 0 0 0 0 165,528 170,320 >75% Grass cover, Good Paved parking TOTAL AREA Su Nu
NJ DEP 2-hr WQ Rainfall=1.25", P2=4.09" NJA230139 - REV 2 Prepared by Bohler Engineering, PC HydroCAD® 10.20-7a s/n 03478 © 2025 HydroCAD Software Solutions LLC Printed 12/11/2025 Page 6 Time span=0.00-72.00 hrs, dt=0.10 hrs, 721 points x 9 Runoff by SCS TR-20 method, UH=SCS, Split Pervious/Imperv. Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Subcatchment E1i: Existing Impervious Subcatchment E1p: Existing Pervious Runoff Area=1.930 ac 100.00% Impervious Runoff Depth=1.03" Flow Length=441' Tc=3.1 min CN=0/98 Runoff=5.44 cfs 7,248 cf Runoff Area=0.020 ac 0.00% Impervious Runoff Depth=0.00" Flow Length=526' Tc=8.2 min CN=39/0 Runoff=0.00 cfs 0 cf Subcatchment P1i: Proposed Impervious Runoff Area=1.600 ac 100.00% Impervious Runoff Depth=1.03" Flow Length=443' Tc=3.0 min CN=0/98 Runoff=4.50 cfs 6,009 cf Runoff Area=0.270 ac 100.00% Impervious Runoff Depth=1.03" Flow Length=30' Slope=0.0150 '/' Tc=0.5 min CN=0/98 Runoff=0.81 cfs 1,014 cf Subcatchment P1i(pp): Proposed Subcatchment P1p: Proposed Pervious Runoff Area=0.090 ac 0.00% Impervious Runoff Depth=0.00" Flow Length=528' Tc=8.1 min CN=39/0 Runoff=0.00 cfs 0 cf Pond PP1: Pervious Pavement Peak Elev=366.95' Storage=1,014 cf Inflow=0.81 cfs 1,014 cf Outflow=0.00 cfs 0 cf Link E1: EDA 1A Inflow=5.44 cfs 7,248 cf Primary=5.44 cfs 7,248 cf Link P1: PDA 1A Inflow=4.50 cfs 6,009 cf Primary=4.50 cfs 6,009 cf Total Runoff Area = 170,320 sf Runoff Volume = 14,271 cf Average Runoff Depth = 1.01" 2.81% Pervious = 4,792 sf 97.19% Impervious = 165,528 sf
NJ DEP 2-hr WQ Rainfall=1.25", P2=4.09" NJA230139 - REV 2 Prepared by Bohler Engineering, PC HydroCAD® 10.20-7a s/n 03478 © 2025 HydroCAD Software Solutions LLC Printed 12/11/2025 Page 7 Summary for Subcatchment E1i: Existing Impervious Runoff = 5.44 cfs @ Routed to Link E1 : EDA 1A 1.05 hrs, Volume= 7,248 cf, Depth= 1.03" Runoff by SCS TR-20 method, UH=SCS, Split Pervious/Imperv., Time Span= 0.00-72.00 hrs, dt= 0.10 hrs NJ DEP 2-hr WQ Rainfall=1.25", P2=4.09" Area (ac) 1.930 1.930 CN 98 98 Description Paved parking, HSG A 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 0.8 100 0.0400 2.05 Sheet Flow, Smooth surfaces n= 0.011 P2= 4.09" 0.1 36 0.0400 4.06 Shallow Concentrated Flow, Paved Kv= 20.3 fps 2.1 285 0.0120 2.22 Shallow Concentrated Flow, Paved Kv= 20.3 fps 0.1 20 0.6600 4.06 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 3.1 441 Total Subcatchment E1i: Existing Impervious Hydrograph 6 Runoff 5.44 cfs NJ DEP 2-hr WQ Rainfall=1.25" P2=4.09" Runoff Area=1.930 ac Runoff Volume=7,248 cf Runoff Depth=1.03" Flow Length=441' Tc=3.1 min CN=0/98 5 Flow (cfs) 4 3 2 1 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)
NJ DEP 2-hr WQ Rainfall=1.25", P2=4.09" NJA230139 - REV 2 Prepared by Bohler Engineering, PC HydroCAD® 10.20-7a s/n 03478 © 2025 HydroCAD Software Solutions LLC Printed 12/11/2025 Page 8 Summary for Subcatchment E1p: Existing Pervious Runoff = 0.00 cfs @ Routed to Link E1 : EDA 1A 0.00 hrs, Volume= 0 cf, Depth= 0.00" Runoff by SCS TR-20 method, UH=SCS, Split Pervious/Imperv., Time Span= 0.00-72.00 hrs, dt= 0.10 hrs NJ DEP 2-hr WQ Rainfall=1.25", P2=4.09" Area (ac) 0.020 0.020 CN 39 39 Description >75% Grass cover, Good, HSG A 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.3 85 0.0500 0.27 Sheet Flow, Grass: Short n= 0.150 P2= 4.09" 0.2 15 0.0400 1.40 Sheet Flow, Smooth surfaces n= 0.011 P2= 4.09" 0.5 121 0.0400 4.06 Shallow Concentrated Flow, Paved Kv= 20.3 fps 2.1 285 0.0120 2.22 Shallow Concentrated Flow, Paved Kv= 20.3 fps 0.1 20 0.6600 4.06 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 8.2 526 Total Subcatchment E1p: Existing Pervious Hydrograph 1 Runoff Flow (cfs) NJ DEP 2-hr WQ Rainfall=1.25" P2=4.09" Runoff Area=0.020 ac Runoff Volume=0 cf Runoff Depth=0.00" Flow Length=526' Tc=8.2 min CN=39/0 0.00 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)
NJ DEP 2-hr WQ Rainfall=1.25", P2=4.09" NJA230139 - REV 2 Prepared by Bohler Engineering, PC HydroCAD® 10.20-7a s/n 03478 © 2025 HydroCAD Software Solutions LLC Printed 12/11/2025 Page 9 Summary for Subcatchment P1i: Proposed Impervious Runoff = 4.50 cfs @ Routed to Link P1 : PDA 1A 1.05 hrs, Volume= 6,009 cf, Depth= 1.03" Runoff by SCS TR-20 method, UH=SCS, Split Pervious/Imperv., Time Span= 0.00-72.00 hrs, dt= 0.10 hrs NJ DEP 2-hr WQ Rainfall=1.25", P2=4.09" Area (ac) 1.600 1.600 CN 98 98 Description Paved parking, HSG A 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 0.8 100 0.0400 2.05 Sheet Flow, Smooth surfaces n= 0.011 P2= 4.09" 0.1 36 0.0400 4.06 Shallow Concentrated Flow, Paved Kv= 20.3 fps 2.0 287 0.0140 2.40 Shallow Concentrated Flow, Paved Kv= 20.3 fps 0.1 20 0.6600 4.06 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 3.0 443 Total Subcatchment P1i: Proposed Impervious Hydrograph 5 Runoff 4.50 cfs NJ DEP 2-hr WQ Rainfall=1.25" P2=4.09" Runoff Area=1.600 ac Runoff Volume=6,009 cf Runoff Depth=1.03" Flow Length=443' Tc=3.0 min CN=0/98 Flow (cfs) 4 3 2 1 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)
NJ DEP 2-hr WQ Rainfall=1.25", P2=4.09" NJA230139 - REV 2 Prepared by Bohler Engineering, PC HydroCAD® 10.20-7a s/n 03478 © 2025 HydroCAD Software Solutions LLC Printed 12/11/2025 Page 10 Summary for Subcatchment P1i(pp): Proposed Impervious Runoff = 0.81 cfs @ 1.01 hrs, Volume= Routed to Pond PP1 : Pervious Pavement 1,014 cf, Depth= 1.03" Runoff by SCS TR-20 method, UH=SCS, Split Pervious/Imperv., Time Span= 0.00-72.00 hrs, dt= 0.10 hrs NJ DEP 2-hr WQ Rainfall=1.25", P2=4.09" Area (ac) 0.270 0.270 CN 98 98 Description Paved parking, HSG A 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 0.5 30 0.0150 1.09 Sheet Flow, Smooth surfaces n= 0.011 P2= 4.09" Subcatchment P1i(pp): Proposed Impervious Hydrograph 0.9 Runoff 0.81 cfs 0.85 NJ DEP 2-hr WQ Rainfall=1.25" P2=4.09" Runoff Area=0.270 ac Runoff Volume=1,014 cf Runoff Depth=1.03" Flow Length=30' Slope=0.0150 '/' Tc=0.5 min CN=0/98 0.8 0.75 0.7 0.65 0.6 Flow (cfs) 0.55 0.5 0.45 0.4 0.35 0.3 0.25 0.2 0.15 0.1 0.05 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)
NJ DEP 2-hr WQ Rainfall=1.25", P2=4.09" NJA230139 - REV 2 Prepared by Bohler Engineering, PC HydroCAD® 10.20-7a s/n 03478 © 2025 HydroCAD Software Solutions LLC Printed 12/11/2025 Page 11 Summary for Subcatchment P1p: Proposed Pervious Runoff = 0.00 cfs @ Routed to Link P1 : PDA 1A 0.00 hrs, Volume= 0 cf, Depth= 0.00" Runoff by SCS TR-20 method, UH=SCS, Split Pervious/Imperv., Time Span= 0.00-72.00 hrs, dt= 0.10 hrs NJ DEP 2-hr WQ Rainfall=1.25", P2=4.09" Area (ac) 0.090 0.090 CN 39 39 Description >75% Grass cover, Good, HSG A 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.3 85 0.0500 0.27 Sheet Flow, Grass: Short n= 0.150 P2= 4.09" 0.2 15 0.0400 1.40 Sheet Flow, Smooth surfaces n= 0.011 P2= 4.09" 0.5 121 0.0400 4.06 Shallow Concentrated Flow, Paved Kv= 20.3 fps 2.0 287 0.0140 2.40 Shallow Concentrated Flow, Paved Kv= 20.3 fps 0.1 20 0.6600 4.06 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 8.1 528 Total Subcatchment P1p: Proposed Pervious Hydrograph 1 Runoff Flow (cfs) NJ DEP 2-hr WQ Rainfall=1.25" P2=4.09" Runoff Area=0.090 ac Runoff Volume=0 cf Runoff Depth=0.00" Flow Length=528' Tc=8.1 min CN=39/0 0.00 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)
NJ DEP 2-hr WQ Rainfall=1.25", P2=4.09" NJA230139 - REV 2 Prepared by Bohler Engineering, PC HydroCAD® 10.20-7a s/n 03478 © 2025 HydroCAD Software Solutions LLC Printed 12/11/2025 Page 12 Summary for Pond PP1: Pervious Pavement Inflow Area = 11,761 sf,100.00% Impervious, Inflow Depth = 1.03" for WQ event Inflow = 0.81 cfs @ 1.01 hrs, Volume= 1,014 cf Outflow = 0.00 cfs @ 0.00 hrs, Volume= 0 cf, Atten= 100%, Lag= 0.0 min Primary = 0.00 cfs @ 0.00 hrs, Volume= 0 cf Routed to Link P1 : PDA 1A Routing by Dyn-Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.10 hrs / 9 Peak Elev= 366.95' @ 2.10 hrs Surf.Area= 8,538 sf Storage= 1,014 cf Plug-Flow detention time= (not calculated: initial storage exceeds outflow) Center-of-Mass det. time= (not calculated: no outflow) Volume #1 Invert 366.65' Elevation (feet) 366.65 367.65 Avail.Storage 3,415 cf Surf.Area (sq-ft) 8,538 8,538 Device #1 Routing Primary Invert 365.50' #2 Device 1 366.95' Storage Description Custom Stage Data (Prismatic)Listed below (Recalc) 8,538 cf Overall x 40.0% Voids Inc.Store (cubic-feet) 0 8,538 Cum.Store (cubic-feet) 0 8,538 Outlet Devices 15.0" Round RCP_Round 15" L= 273.0' RCP, groove end projecting, Ke= 0.200 Inlet / Outlet Invert= 365.50' / 364.15' S= 0.0049 '/' Cc= 0.900 n= 0.011 Concrete pipe, straight & clean, Flow Area= 1.23 sf 4.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=366.65' TW=0.00' (Dynamic Tailwater) 1=RCP_Round 15" (Passes 0.00 cfs of 4.21 cfs potential flow) 2=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs)
File revisions (1)
- Sep 29, 2026
671005d8c0ae8,670,806 bytes