2026 05 Storm Water Management Report rcd 5 6 2026

Link 1L: POI #1 Link 2L: POI #2 Hydrograph Hydrograph Inflow Inflow 4.45 cfs Primary 0.30 cfs Primary 4.45 cfs 0.32 0.30 cfs Inflow Area=0.534 ac 0.3 Inflow Area=0.044 ac 0.28 4 0.26 0.24 0.22 3 0.2 Flow (cfs)

0.2 Flow (cfs) Flow (cfs) 0.18 0.16 0.14 2 0.12 0.1 0.08 1 0.06 0.04 0.02 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)

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 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 47 HydroCAD® 10.20-7a s/n 08640 © 2025 HydroCAD Software Solutions LLC Page 48 Summary for Link 3L: POI #3 Summary for Subcatchment 1S: EDA #1 - Impervious Inflow Area = 0.103 ac, 18.45% Impervious, Inflow Depth = 5.21" for 100-Year-Current event Runoff = 4.57 cfs @ 12.10 hrs, Volume= 0.354 af, Depth=11.28" Inflow = 0.53 cfs @ 12.16 hrs, Volume= 0.045 af Routed to Link 1L : POI #1 Primary = 0.53 cfs @ 12.16 hrs, Volume= 0.045 af, Atten= 0%, Lag= 0.0 min Routed to nonexistent node 15L 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-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 Link 3L: POI #3

Area (ac) CN Description Link 3L: POI #3 0.377 98 Paved parking, HSG B Hydrograph 0.377 100.00% Impervious Area Inflow Tc Length Slope Velocity Capacity Description 0.53 cfs Primary 0.53 cfs (min) (feet) (ft/ft) (ft/sec) (cfs) 0.55 Inflow Area=0.103 ac 1.4 100 0.0100 1.18 Sheet Flow, A-B 0.5 Smooth surfaces n= 0.011 P2= 4.09" 0.2 119 0.0400 10.53 12.92 Pipe Channel, B-C 0.45 15.0" Round Area= 1.2 sf Perim= 3.9' r= 0.31' 0.4 n= 0.013 Corrugated PE, smooth interior 1.6 219 Total 0.35 Flow (cfs) 0.3

1.6 219 Total 0.35 Flow (cfs) 0.3 Subcatchment 1S: EDA #1 - Impervious 0.25 Hydrograph 0.2 5 Runoff 4.57 cfs 0.15 NOAA 24-hr D 0.1 100-Year-Projected Rainfall=11.52" 4 P2=4.09" 0.05 Runoff Area=0.377 ac 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

Runoff Area=0.377 ac 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 Runoff Volume=0.354 af Time (hours) Runoff Depth=11.28" 3 Flow (cfs) Flow Length=219' Tc=1.6 min CN=98 2 1 0 0 2 4 6 8 10 12 14 16 18 20

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 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 49 HydroCAD® 10.20-7a s/n 08640 © 2025 HydroCAD Software Solutions LLC Page 50 Summary for Subcatchment 2S: EDA #1 - Pervious Summary for Subcatchment 3S: EDA #2 - Impervious Runoff = 1.23 cfs @ 12.12 hrs, Volume= 0.082 af, Depth= 6.31" Runoff = 0.18 cfs @ 12.10 hrs, Volume= 0.014 af, Depth=11.28" Routed to Link 1L : POI #1 Routed to Link 2L : POI #2 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-Projected Rainfall=11.52", P2=4.09" NOAA 24-hr D 100-Year-Projected Rainfall=11.52", P2=4.09" Area (ac) CN Description Area (ac) CN Description 0.157 61 >75% Grass cover, Good, HSG B 0.015 98 Paved parking, HSG B 0.157 100.00% Pervious Area

0.015 98 Paved parking, HSG B 0.157 100.00% Pervious Area 0.015 100.00% Impervious 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) 3.7 34 0.0500 0.15 Sheet Flow, A-B 0.5 42 0.0260 1.45 Sheet Flow, A-B Grass: Dense n= 0.240 P2= 4.09" Smooth surfaces n= 0.011 P2= 4.09" 0.5 124 0.0410 4.11 Shallow Concentrated Flow, B-C 0.3 58 0.0300 3.52 Shallow Concentrated Flow, B-C Paved Kv= 20.3 fps Paved Kv= 20.3 fps 0.1 13 0.0030 2.69 2.11 Pipe Channel, C-D 0.8 100 Total 12.0" Round Area= 0.8 sf Perim= 3.1' r= 0.25' n= 0.012 Concrete pipe, finished Subcatchment 3S: EDA #2 - 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