Supporting Documentation · May 28, 2026
2026 05 Storm Water Management Report rcd 5 6 2026
ca1b6a05d93acd17db8ba3736caf854fbeada41956eb0ec8f599e95e0e23a985Indexed text
6 Runoff Runoff 0.14 cfs 0.17 0.16 cfs 0.15 NOAA 24-hr D 0.16 NOAA 24-hr D 0.14 0.15 0.13 100-Year-Current Rainfall=9.18" 100-Year-Current Rainfall=9.18" 0.14 0.12 P2=3.47" 0.13 P2=3.47" 0.11 Runoff Area=0.015 ac 0.12 Runoff Area=0.029 ac 0.1 Runoff Volume=0.011 af 0.11 Runoff Volume=0.011 af
0.11 Runoff Volume=0.011 af Runoff Depth=8.94" Runoff Depth=4.37" Flow (cfs) Flow (cfs) 0.09 0.1 0.08 Flow Length=100' 0.09 Flow Length=153' 0.08 0.07 Tc=0.8 min Tc=4.4 min 0.07 0.06 CN=98 CN=61 0.06 0.05 0.05 0.04 0.04 0.03
0.04 0.04 0.03 0.03 0.02 0.02 0.01 0.01 0 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 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) Time (hours)
2026-04 Proposed & Existing CondiNOAA 24-hr D 100-Year-Current Rainfall=9.18", P2=3.47" 2026-04 Proposed & Existing CondiNOAA 24-hr D 100-Year-Current Rainfall=9.18", P2=3.47" Prepared by Dynamic Engineering Printed 5/5/2026 Prepared by Dynamic Engineering Printed 5/5/2026 HydroCAD® 10.20-7a s/n 08640 © 2025 HydroCAD Software Solutions LLC Page 43 HydroCAD® 10.20-7a s/n 08640 © 2025 HydroCAD Software Solutions LLC Page 44 Summary for Subcatchment 5S: EDA #3 - Impervious Summary for Subcatchment 6S: EDA #2 - Pervious Runoff = 0.15 cfs @ 12.15 hrs, Volume= 0.014 af, Depth= 8.94" Runoff = 0.38 cfs @ 12.16 hrs, Volume= 0.031 af, Depth= 4.37" Routed to Link 3L : POI #3 Routed to Link 3L : POI #3 Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.001 hrs Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.001 hrs NOAA 24-hr D 100-Year-Current Rainfall=9.18", P2=3.47" NOAA 24-hr D 100-Year-Current Rainfall=9.18", P2=3.47" Area (ac) CN Description Area (ac) CN Description 0.019 98 Unconnected pavement, HSG B 0.084 61 >75% Grass cover, Good, HSG B 0.019 100.00% Impervious Area
0.084 61 >75% Grass cover, Good, HSG B 0.019 100.00% Impervious Area 0.084 100.00% Pervious Area 0.019 100.00% Unconnected Tc Length Slope Velocity Capacity Description Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) (min) (feet) (ft/ft) (ft/sec) (cfs) 9.2 100 0.0540 0.18 Sheet Flow, A-B 0.2 9 0.0200 0.88 Sheet Flow, A-B Grass: Dense n= 0.240 P2= 3.47" Smooth surfaces n= 0.011 P2= 3.47" 0.1 16 0.0540 3.49 Shallow Concentrated Flow, B-C 8.5 91 0.0540 0.18 Sheet Flow, B-C Grassed Waterway Kv= 15.0 fps Grass: Dense n= 0.240 P2= 3.47" 9.3 116 Total 0.0 7 0.0540 3.49 Shallow Concentrated Flow, C-D Grassed Waterway Kv= 15.0 fps Subcatchment 6S: EDA #2 - Pervious 8.7 107 Total Hydrograph
Hydrograph Subcatchment 5S: EDA #3 - Impervious 0.42 Runoff 0.4 0.38 cfs Hydrograph 0.38 NOAA 24-hr D 0.17 0.36 Runoff 100-Year-Current Rainfall=9.18" 0.16 0.15 cfs 0.34 0.32 P2=3.47" 0.15 NOAA 24-hr D 0.3 Runoff Area=0.084 ac 0.14 100-Year-Current Rainfall=9.18"
Runoff Area=0.084 ac 0.14 100-Year-Current Rainfall=9.18" 0.28 0.26 Runoff Volume=0.031 af 0.13 P2=3.47" Runoff Depth=4.37" Flow (cfs) 0.24 0.12 Runoff Area=0.019 ac 0.22 0.11 Flow Length=116' Runoff Volume=0.014 af 0.2 0.1 0.18 Slope=0.0540 '/' Runoff Depth=8.94" Flow (cfs) 0.09 0.16
0.16 Tc=9.3 min Flow Length=107' 0.14 0.08 CN=61 0.07 Tc=8.7 min 0.12 0.1 0.06 CN=98 0.08 0.05 0.06 0.04 0.04 0.02 0.03 0 0.02 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) 0.01 0
Time (hours) 0.01 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)
2026-04 Proposed & Existing CondiNOAA 24-hr D 100-Year-Current Rainfall=9.18", P2=3.47" 2026-04 Proposed & Existing CondiNOAA 24-hr D 100-Year-Current Rainfall=9.18", P2=3.47" Prepared by Dynamic Engineering Printed 5/5/2026 Prepared by Dynamic Engineering Printed 5/5/2026 HydroCAD® 10.20-7a s/n 08640 © 2025 HydroCAD Software Solutions LLC Page 45 HydroCAD® 10.20-7a s/n 08640 © 2025 HydroCAD Software Solutions LLC Page 46 Summary for Link 1L: POI #1 Summary for Link 2L: POI #2 Inflow Area = 0.534 ac, 70.60% Impervious, Inflow Depth = 7.60" for 100-Year-Current event Inflow Area = 0.044 ac, 34.09% Impervious, Inflow Depth = 5.93" for 100-Year-Current event Inflow = 4.45 cfs @ 12.10 hrs, Volume= 0.338 af Inflow = 0.30 cfs @ 12.10 hrs, Volume= 0.022 af Primary = 4.45 cfs @ 12.10 hrs, Volume= 0.338 af, Atten= 0%, Lag= 0.0 min Primary = 0.30 cfs @ 12.10 hrs, Volume= 0.022 af, Atten= 0%, Lag= 0.0 min Routed to nonexistent node 15L Routed to nonexistent node 15L Primary outflow = Inflow, Time Span= 0.00-72.00 hrs, dt= 0.001 hrs Primary outflow = Inflow, Time Span= 0.00-72.00 hrs, dt= 0.001 hrs Link 1L: POI #1 Link 2L: POI #2
File revisions (1)
- Sep 29, 2026
ca1b6a05d93a18,504,890 bytes