2026 05 Storm Water Management Report rcd 5 6 2026

2026-04 Proposed & Existing Conditi NOAA 24-hr D 2-Year-Current Rainfall=3.47", P2=3.47" 2026-04 Proposed & Existing Conditi NOAA 24-hr D 2-Year-Current Rainfall=3.47", 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 3 HydroCAD® 10.20-7a s/n 08640 © 2025 HydroCAD Software Solutions LLC Page 4 Summary for Subcatchment 1S: EDA #1 - Impervious Summary for Subcatchment 2S: EDA #1 - Pervious Runoff = 1.36 cfs @ 12.10 hrs, Volume= 0.102 af, Depth= 3.24" Runoff = 0.09 cfs @ 12.13 hrs, Volume= 0.007 af, Depth= 0.56" Routed to Link 1L : POI #1 Routed to Link 1L : POI #1 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-Current Rainfall=3.47", P2=3.47" NOAA 24-hr D 2-Year-Current Rainfall=3.47", P2=3.47" Area (ac) CN Description Area (ac) CN Description 0.377 98 Paved parking, HSG B 0.157 61 >75% Grass cover, Good, HSG B 0.377 100.00% Impervious Area

0.157 61 >75% Grass cover, Good, HSG B 0.377 100.00% Impervious Area 0.157 100.00% 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) 1.5 100 0.0100 1.09 Sheet Flow, A-B 4.0 34 0.0500 0.14 Sheet Flow, A-B Smooth surfaces n= 0.011 P2= 3.47" Grass: Dense n= 0.240 P2= 3.47" 0.2 119 0.0400 10.53 12.92 Pipe Channel, B-C 0.5 124 0.0410 4.11 Shallow Concentrated Flow, B-C 15.0" Round Area= 1.2 sf Perim= 3.9' r= 0.31' Paved Kv= 20.3 fps n= 0.013 Corrugated PE, smooth interior 0.1 13 0.0030 2.69 2.11 Pipe Channel, C-D 1.7 219 Total 12.0" Round Area= 0.8 sf Perim= 3.1' r= 0.25' n= 0.012 Concrete pipe, finished Subcatchment 1S: EDA #1 - Impervious 0.2 96 0.0144 6.84 8.40 Pipe Channel, D-E

chment 1S: EDA #1 - Impervious 0.2 96 0.0144 6.84 8.40 Pipe Channel, D-E 15.0" Round Area= 1.2 sf Perim= 3.9' r= 0.31' Hydrograph n= 0.012 Concrete pipe, finished 4.8 267 Total Runoff 1.36 cfs NOAA 24-hr D Subcatchment 2S: EDA #1 - Pervious 2-Year-Current Rainfall=3.47" Hydrograph P2=3.47" 0.095 Runoff Runoff Area=0.377 ac 0.09 0.09 cfs 1 Runoff Volume=0.102 af 0.085 NOAA 24-hr D Flow (cfs)

085 NOAA 24-hr D Flow (cfs) Runoff Depth=3.24" 0.08 2-Year-Current Rainfall=3.47" 0.075 Flow Length=219' 0.07 P2=3.47" Tc=1.7 min 0.065 Runoff Area=0.157 ac 0.06 Runoff Volume=0.007 af CN=98 Flow (cfs) 0.055 Runoff Depth=0.56"

Runoff Depth=0.56" 0.05 0.045 Flow Length=267' 0.04 Tc=4.8 min 0.035 CN=61 0.03 0 0.025 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) 0.02 0.015 0.01 0.005

0.005 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)