2026 05 Storm Water Management Report rcd 5 6 2026

2026-04 Proposed & Existing CoNOAA 24-hr D 100-Year-Projected Rainfall=11.52", P2=4.09" 2026-04 Proposed & Existing CoNOAA 24-hr D 100-Year-Projected Rainfall=11.52", 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 53 HydroCAD® 10.20-7a s/n 08640 © 2025 HydroCAD Software Solutions LLC Page 54 Summary for Subcatchment 6S: EDA #2 - Pervious Summary for Link 1L: POI #1 Runoff = 0.57 cfs @ 12.16 hrs, Volume= 0.044 af, Depth= 6.31" Inflow Area = 0.534 ac, 70.60% Impervious, Inflow Depth = 9.82" for 100-Year-Projected event Routed to Link 3L : POI #3 Inflow = 5.76 cfs @ 12.10 hrs, Volume= 0.437 af Primary = 5.76 cfs @ 12.10 hrs, Volume= 0.437 af, Atten= 0%, Lag= 0.0 min Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.001 hrs Routed to nonexistent node 15L NOAA 24-hr D 100-Year-Projected Rainfall=11.52", P2=4.09" Primary outflow = Inflow, Time Span= 0.00-72.00 hrs, dt= 0.001 hrs Area (ac) CN Description 0.084 61 >75% Grass cover, Good, HSG B

a (ac) CN Description 0.084 61 >75% Grass cover, Good, HSG B Link 1L: POI #1 0.084 100.00% Pervious Area Hydrograph Tc Length Slope Velocity Capacity Description Inflow 5.76 cfs Primary (min) (feet) (ft/ft) (ft/sec) (cfs) 5.76 cfs 8.5 100 0.0540 0.20 Sheet Flow, A-B 6 Inflow Area=0.534 ac Grass: Dense n= 0.240 P2= 4.09" 0.1 16 0.0540 3.49 Shallow Concentrated Flow, B-C 5 Grassed Waterway Kv= 15.0 fps 8.6 116 Total 4 Flow (cfs) Subcatchment 6S: EDA #2 - Pervious

Flow (cfs) Subcatchment 6S: EDA #2 - Pervious Hydrograph 3 Runoff 0.6 0.57 cfs 2 0.55 NOAA 24-hr D 100-Year-Projected Rainfall=11.52" 0.5 P2=4.09" 1 0.45 Runoff Area=0.084 ac 0.4 Runoff Volume=0.044 af 0 Runoff Depth=6.31" 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 Flow (cfs) 0.35 Time (hours) Flow Length=116' 0.3 Slope=0.0540 '/' 0.25

0.3 Slope=0.0540 '/' 0.25 Tc=8.6 min CN=61 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)