Stormwater Management Report 03302026

24-223 DRAINAGE DESIGN-PROPOSED-2026-03-30 NOAA 24-hr D 2-Year-2020 Rainfall=3.47", P2=3.47" Prepared by Jarmel Kizel Architects & Engnrs Printed 3/30/2026 HydroCAD® 10.20-6a s/n 12607 © 2024 HydroCAD Software Solutions LLC Page 11 Summary for Subcatchment P3A-IMP: P3A IMPERVIOUS Runoff = 0.17 cfs @ 12.01 hrs, Volume= 1,090 cf, Depth= 3.24" Routed to Link P-DP 2 : PROP DP 2 Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.50 hrs NOAA 24-hr D 2-Year-2020 Rainfall=3.47", P2=3.47" Area (sf) CN Description * 4,040 98 DRIVE/SIDEWALK 4,040 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 0.8 100 0.0500 2.07 Sheet Flow, Pavement Smooth surfaces n= 0.011 P2= 3.47" 1.2 335 0.0500 4.54 Shallow Concentrated Flow, shadow concentrate Paved Kv= 20.3 fps 2.0 435 Total

24-223 DRAINAGE DESIGN-PROPOSED-2026-03-30 NOAA 24-hr D 2-Year-2020 Rainfall=3.47", P2=3.47" Prepared by Jarmel Kizel Architects & Engnrs Printed 3/30/2026 HydroCAD® 10.20-6a s/n 12607 © 2024 HydroCAD Software Solutions LLC Page 12 Subcatchment P3A-IMP: P3A IMPERVIOUS Hydrograph 0.19 Runoff 0.18 0.17 cfs 0.17 NOAA 24-hr D 0.16 0.15 2-Year-2020 Rainfall=3.47" 0.14 P2=3.47" 0.13 0.12 Runoff Area=4,040 sf 0.11 Runoff Volume=1,090 cf Flow (cfs) 0.1 0.09 Runoff Depth=3.24" 0.08 Flow Length=435' 0.07 0.06 Slope=0.0500 '/' 0.05 Tc=2.0 min 0.04 CN=98 0.03 0.02 0.01 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Time (hours)

24-223 DRAINAGE DESIGN-PROPOSED-2026-03-30 NOAA 24-hr D 2-Year-2020 Rainfall=3.47", P2=3.47" Prepared by Jarmel Kizel Architects & Engnrs Printed 3/30/2026 HydroCAD® 10.20-6a s/n 12607 © 2024 HydroCAD Software Solutions LLC Page 13 Summary for Subcatchment P3A-P: P3A PERVIOUS Runoff = 0.09 cfs @ 12.08 hrs, Volume= 602 cf, Depth= 1.22" Routed to Link P-DP 2 : PROP DP 2 Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.50 hrs NOAA 24-hr D 2-Year-2020 Rainfall=3.47", P2=3.47" Area (sf) CN Description 5,928 74 >75% Grass cover, Good, HSG C 5,928 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.1 100 0.0600 0.27 Sheet Flow, sheet flow Grass: Short n= 0.150 P2= 3.47" 0.1 29 0.0550 3.78 Shallow Concentrated Flow, Lawn Unpaved Kv= 16.1 fps 6.2 129 Total

24-223 DRAINAGE DESIGN-PROPOSED-2026-03-30 NOAA 24-hr D 2-Year-2020 Rainfall=3.47", P2=3.47" Prepared by Jarmel Kizel Architects & Engnrs Printed 3/30/2026 HydroCAD® 10.20-6a s/n 12607 © 2024 HydroCAD Software Solutions LLC Page 14 Subcatchment P3A-P: P3A PERVIOUS Hydrograph 0.1 Runoff 0.095 0.09 cfs 0.09 NOAA 24-hr D 0.085 0.08 2-Year-2020 Rainfall=3.47" 0.075 0.07 P2=3.47" 0.065 Runoff Area=5,928 sf 0.06 Runoff Volume=602 cf Flow (cfs) 0.055 0.05 Runoff Depth=1.22" 0.045 0.04 Flow Length=129' 0.035 0.03 Tc=6.2 min 0.025 CN=74 0.02 0.015 0.01 0.005 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Time (hours)

24-223 DRAINAGE DESIGN-PROPOSED-2026-03-30 NOAA 24-hr D 2-Year-2020 Rainfall=3.47", P2=3.47" Prepared by Jarmel Kizel Architects & Engnrs Printed 3/30/2026 HydroCAD® 10.20-6a s/n 12607 © 2024 HydroCAD Software Solutions LLC Page 15 Summary for Subcatchment P3B-IMP: P3B IMPERVIOUS Runoff = 0.04 cfs @ 12.00 hrs, Volume= 264 cf, Depth= 3.24" Routed to Link P-DP 2 : PROP DP 2 Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.50 hrs NOAA 24-hr D 2-Year-2020 Rainfall=3.47", P2=3.47" Area (sf) CN Description * 980 98 SIDEWALK AREA 980 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 0.6 100 0.0900 2.61 Sheet Flow, sidewalk Smooth surfaces n= 0.011 P2= 3.47" 0.5 88 0.0220 3.01 Shallow Concentrated Flow, shadow concentrate Paved Kv= 20.3 fps 1.1 188 Total

24-223 DRAINAGE DESIGN-PROPOSED-2026-03-30 NOAA 24-hr D 2-Year-2020 Rainfall=3.47", P2=3.47" Prepared by Jarmel Kizel Architects & Engnrs Printed 3/30/2026 HydroCAD® 10.20-6a s/n 12607 © 2024 HydroCAD Software Solutions LLC Page 16 Subcatchment P3B-IMP: P3B IMPERVIOUS Hydrograph 0.046 Runoff 0.044 0.04 cfs 0.042 0.04 NOAA 24-hr D 0.038 0.036 2-Year-2020 Rainfall=3.47" 0.034 0.032 P2=3.47" 0.03 0.028 Runoff Area=980 sf Runoff Volume=264 cf Flow (cfs) 0.026 0.024 0.022 Runoff Depth=3.24" 0.02 0.018 Flow Length=188' 0.016 0.014 Tc=1.1 min 0.012 0.01 CN=98 0.008 0.006 0.004 0.002 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

0.002 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Time (hours)

24-223 DRAINAGE DESIGN-PROPOSED-2026-03-30 NOAA 24-hr D 2-Year-2020 Rainfall=3.47", P2=3.47" Prepared by Jarmel Kizel Architects & Engnrs Printed 3/30/2026 HydroCAD® 10.20-6a s/n 12607 © 2024 HydroCAD Software Solutions LLC Page 17 Summary for Subcatchment P3B-P: P3B PERVIOUS Runoff = 0.03 cfs @ 12.08 hrs, Volume= 191 cf, Depth= 1.22" Routed to Link P-DP 2 : PROP DP 2 Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.50 hrs NOAA 24-hr D 2-Year-2020 Rainfall=3.47", P2=3.47" Area (sf) CN Description 1,881 74 >75% Grass cover, Good, HSG C 1,881 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.2 100 0.0900 0.32 Sheet Flow, sheet flow Grass: Short n= 0.150 P2= 3.47" 0.6 88 0.0230 2.44 Shallow Concentrated Flow, Lawn Unpaved Kv= 16.1 fps 5.8 188 Total

24-223 DRAINAGE DESIGN-PROPOSED-2026-03-30 NOAA 24-hr D 2-Year-2020 Rainfall=3.47", P2=3.47" Prepared by Jarmel Kizel Architects & Engnrs Printed 3/30/2026 HydroCAD® 10.20-6a s/n 12607 © 2024 HydroCAD Software Solutions LLC Page 18 Subcatchment P3B-P: P3B PERVIOUS Hydrograph 0.032 Runoff 0.03 cfs 0.03 0.028 NOAA 24-hr D 0.026 2-Year-2020 Rainfall=3.47" 0.024 P2=3.47" 0.022 0.02 Runoff Area=1,881 sf Runoff Volume=191 cf Flow (cfs) 0.018 0.016 Runoff Depth=1.22" 0.014 Flow Length=188' 0.012 0.01 Tc=5.8 min 0.008 CN=74 0.006 0.004 0.002 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Time (hours)