Stormwater Management Report 03302026

24-223 DRAINAGE DESIGN-PROPOSED-2026-03-30 NOAA 24-hr D 10-Year-2020 Rainfall=5.38", 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 39 Summary for Subcatchment P3B-P: P3B PERVIOUS Runoff = 0.07 cfs @ 12.05 hrs, Volume= 419 cf, Depth= 2.67" 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 10-Year-2020 Rainfall=5.38", 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 10-Year-2020 Rainfall=5.38", 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 40 Subcatchment P3B-P: P3B PERVIOUS Hydrograph 0.075 Runoff 0.07 cfs 0.07 0.065 NOAA 24-hr D 0.06 10-Year-2020 Rainfall=5.38" 0.055 P2=3.47" 0.05 Runoff Area=1,881 sf 0.045 Runoff Volume=419 cf Flow (cfs) 0.04 Runoff Depth=2.67" 0.035 0.03 Flow Length=188' 0.025 Tc=5.8 min 0.02 CN=74 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 10-Year-2020 Rainfall=5.38", 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 41 Summary for Subcatchment P3C: P3C- Roof Area Runoff = 0.30 cfs @ 12.00 hrs, Volume= 1,928 cf, Depth= 5.14" 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 10-Year-2020 Rainfall=5.38", P2=3.47" Area (sf) CN Description * 4,500 98 Roof and Amenity Area 4,500 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 0.9 52 0.0100 0.95 Sheet Flow, ROOF Smooth surfaces n= 0.011 P2= 3.47" 0.2 54 0.0216 5.51 1.92 Pipe Channel, 8 ROOF DRAIN 8.0" Round Area= 0.3 sf Perim= 2.1' r= 0.17' n= 0.012 1.1 106 Total

24-223 DRAINAGE DESIGN-PROPOSED-2026-03-30 NOAA 24-hr D 10-Year-2020 Rainfall=5.38", 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 42 Subcatchment P3C: P3C- Roof Area Hydrograph 0.32 Runoff 0.30 cfs 0.3 NOAA 24-hr D 0.28 0.26 10-Year-2020 Rainfall=5.38" 0.24 P2=3.47" 0.22 Runoff Area=4,500 sf 0.2 Runoff Volume=1,928 cf Flow (cfs) 0.18 0.16 Runoff Depth=5.14" 0.14 Flow Length=106' 0.12 Tc=1.1 min 0.1 0.08 CN=98 0.06 0.04 0.02 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 10-Year-2020 Rainfall=5.38", 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 43 Summary for Link 11L: Proposed Disturbed Inflow Area = 69,715 sf, 92.28% Impervious, Inflow Depth = 4.95" for 10-Year-2020 event Inflow = 4.41 cfs @ 12.01 hrs, Volume= 28,768 cf Primary = 4.41 cfs @ 12.01 hrs, Volume= 28,768 cf, Atten= 0%, Lag= 0.0 min Routed to Link P-DP 1 : PROP DP 1 Primary outflow = Inflow, Time Span= 0.00-30.00 hrs, dt= 0.50 hrs Link 11L: Proposed Disturbed Hydrograph Inflow 4.41 cfs Primary 4.41 cfs Inflow Area=69,715 sf 4 3 Flow (cfs) 2 1 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 10-Year-2020 Rainfall=5.38", 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 44 Summary for Link 15L: TOTAL PROPOSED Inflow Area = 133,103 sf, 56.94% Impervious, Inflow Depth = 3.98" for 10-Year-2020 event Inflow = 6.45 cfs @ 12.04 hrs, Volume= 44,160 cf Primary = 6.45 cfs @ 12.04 hrs, Volume= 44,160 cf, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-30.00 hrs, dt= 0.50 hrs Link 15L: TOTAL PROPOSED Hydrograph Inflow 7 6.45 cfs Primary 6.45 cfs Inflow Area=133,103 sf 6 5 Flow (cfs) 4 3 2 1 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 10-Year-2020 Rainfall=5.38", 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 45 Summary for Link P-DP 1: PROP DP 1 Inflow Area = 115,774 sf, 57.23% Impervious, Inflow Depth = 3.97" for 10-Year-2020 event Inflow = 5.54 cfs @ 12.04 hrs, Volume= 38,343 cf Primary = 5.54 cfs @ 12.04 hrs, Volume= 38,343 cf, Atten= 0%, Lag= 0.0 min Routed to Link 15L : TOTAL PROPOSED Primary outflow = Inflow, Time Span= 0.00-30.00 hrs, dt= 0.50 hrs Link P-DP 1: PROP DP 1 Hydrograph Inflow 5.54 cfs Primary 6 5.54 cfs Inflow Area=115,774 sf 5 4 Flow (cfs) 3 2 1 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 10-Year-2020 Rainfall=5.38", 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 46 Summary for Link P-DP 2: PROP DP 2 Inflow Area = 17,329 sf, 54.94% Impervious, Inflow Depth = 4.03" for 10-Year-2020 event Inflow = 0.91 cfs @ 12.02 hrs, Volume= 5,818 cf Primary = 0.91 cfs @ 12.02 hrs, Volume= 5,818 cf, Atten= 0%, Lag= 0.0 min Routed to Link 15L : TOTAL PROPOSED Primary outflow = Inflow, Time Span= 0.00-30.00 hrs, dt= 0.50 hrs Link P-DP 2: PROP DP 2 Hydrograph Inflow 1 0.91 cfs Primary 0.91 cfs Inflow Area=17,329 sf Flow (cfs) 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 100-Year-2020 Rainfall=9.18", 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 47 Summary for Subcatchment 1S: Roof Runoff = 4.51 cfs @ 12.00 hrs, Volume= 29,828 cf, Depth= 8.94" Routed to Link 11L : Proposed Disturbed 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 100-Year-2020 Rainfall=9.18", P2=3.47" Area (sf) CN Description * 40,040 98 Roof and Amenity Area 40,040 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 0.7 53 0.0200 1.26 Sheet Flow, ROOF Smooth surfaces n= 0.011 P2= 3.47" 0.5 196 0.0200 6.95 5.46 Pipe Channel, 12 ROOF DRAIN 12.0" Round Area= 0.8 sf Perim= 3.1' r= 0.25' n= 0.012 0.3 217 0.0424 11.74 14.41 Pipe Channel, 15 15.0" Round Area= 1.2 sf Perim= 3.9' r= 0.31' n= 0.012 1.5 466 Total

24-223 DRAINAGE DESIGN-PROPOSED-2026-03-30 NOAA 24-hr D 100-Year-2020 Rainfall=9.18", 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 48 Subcatchment 1S: Roof Hydrograph 5 Runoff 4.51 cfs NOAA 24-hr D 4 100-Year-2020 Rainfall=9.18" P2=3.47" Runoff Area=40,040 sf 3 Runoff Volume=29,828 cf Flow (cfs) Runoff Depth=8.94" Flow Length=466' 2 Tc=1.5 min CN=98 1 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)