Supporting Documentation · May 28, 2026
2026 05 Storm Water Management Report rcd 5 6 2026
ca1b6a05d93acd17db8ba3736caf854fbeada41956eb0ec8f599e95e0e23a985Indexed text · page 66
Show all pages2026-04 Proposed & Existing CondiNOAA 24-hr D 2-Year-Projected Rainfall=4.09", P2=4.09" 2026-04 Proposed & Existing CondiNOAA 24-hr D 2-Year-Projected Rainfall=4.09", P2=4.09" 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 19 HydroCAD® 10.20-7a s/n 08640 © 2025 HydroCAD Software Solutions LLC Page 20 Summary for Subcatchment 8S: PDA #1 - Impervious to Bio Summary for Subcatchment 9S: PDA #1 - Pervious to Bio Runoff = 0.33 cfs @ 12.10 hrs, Volume= 0.025 af, Depth= 3.85" Runoff = 0.18 cfs @ 12.12 hrs, Volume= 0.012 af, Depth= 2.12" Routed to Pond 2P : BIO BASIN Routed to Pond 2P : BIO BASIN 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 2-Year-Projected Rainfall=4.09", P2=4.09" NOAA 24-hr D 2-Year-Projected Rainfall=4.09", P2=4.09" Area (ac) CN Description Area (ac) CN Description 0.078 98 Paved parking, HSG D 0.068 80 >75% Grass cover, Good, HSG D 0.078 100.00% Impervious Area
0.068 80 >75% Grass cover, Good, HSG D 0.078 100.00% Impervious Area 0.068 100.00% Pervious Area 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) 0.4 42 0.0326 1.59 Sheet Flow, A-B 4.8 45 0.0450 0.16 Sheet Flow, A-B Smooth surfaces n= 0.011 P2= 4.09" Grass: Dense n= 0.240 P2= 4.09" 0.1 18 0.1180 5.53 Shallow Concentrated Flow, B-C (RIP-RAP) 0.2 29 0.0148 2.47 Shallow Concentrated Flow, B-C Unpaved Kv= 16.1 fps Paved Kv= 20.3 fps 0.5 60 Total 0.1 18 0.1180 5.53 Shallow Concentrated Flow, C-D (RIP-RAP) Unpaved Kv= 16.1 fps Subcatchment 8S: PDA #1 - Impervious to Bio 5.1 92 Total Hydrograph
Hydrograph Subcatchment 9S: PDA #1 - Pervious to Bio Runoff Hydrograph 0.36 0.33 cfs 0.34 NOAA 24-hr D Runoff 0.32 0.19 0.18 cfs 0.3 2-Year-Projected Rainfall=4.09" 0.18 NOAA 24-hr D 0.28 P2=4.09" 0.17 0.26 0.16 2-Year-Projected Rainfall=4.09" Runoff Area=0.078 ac 0.15 0.24 P2=4.09" 0.22
P2=4.09" 0.22 Runoff Volume=0.025 af 0.14 Runoff Area=0.068 ac Flow (cfs) 0.2 Runoff Depth=3.85" 0.13 0.18 Flow Length=60' 0.12 Runoff Volume=0.012 af Flow (cfs) 0.11 0.16 Tc=0.5 min Runoff Depth=2.12" 0.1 0.14 CN=98 0.09 Flow Length=92' 0.12
Flow Length=92' 0.12 0.08 Tc=5.1 min 0.1 0.08 0.07 CN=80 0.06 0.06 0.05 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 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)
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- Sep 29, 2026
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