Stormwater Management Report 03302026

24-223 DRAINAGE DESIGN-PROPOSED-2026-03-30 NOAA 24-hr D 10-Year-2050 Rainfall=6.37", P2=4.09" Prepared by Jarmel Kizel Architects & Engnrs Printed 3/30/2026 HydroCAD® 10.20-6a s/n 12607 © 2024 HydroCAD Software Solutions LLC Page 103 Summary for Subcatchment P3B-IMP: P3B IMPERVIOUS Runoff = 0.08 cfs @ 12.00 hrs, Volume= 501 cf, Depth= 6.13" 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-2050 Rainfall=6.37", P2=4.09" 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 2.84 Sheet Flow, sidewalk Smooth surfaces n= 0.011 P2= 4.09" 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 10-Year-2050 Rainfall=6.37", P2=4.09" Prepared by Jarmel Kizel Architects & Engnrs Printed 3/30/2026 HydroCAD® 10.20-6a s/n 12607 © 2024 HydroCAD Software Solutions LLC Page 104 Subcatchment P3B-IMP: P3B IMPERVIOUS Hydrograph 0.085 Runoff 0.08 0.08 cfs 0.075 NOAA 24-hr D 0.07 10-Year-2050 Rainfall=6.37" 0.065 0.06 P2=4.09" 0.055 Runoff Area=980 sf 0.05 Runoff Volume=501 cf Flow (cfs) 0.045 0.04 Runoff Depth=6.13" 0.035 Flow Length=188' 0.03 Tc=1.1 min 0.025 CN=98 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 10-Year-2050 Rainfall=6.37", P2=4.09" Prepared by Jarmel Kizel Architects & Engnrs Printed 3/30/2026 HydroCAD® 10.20-6a s/n 12607 © 2024 HydroCAD Software Solutions LLC Page 105 Summary for Subcatchment P3B-P: P3B PERVIOUS Runoff = 0.09 cfs @ 12.05 hrs, Volume= 548 cf, Depth= 3.50" 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-2050 Rainfall=6.37", P2=4.09" 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) 4.7 100 0.0900 0.35 Sheet Flow, sheet flow Grass: Short n= 0.150 P2= 4.09" 0.6 88 0.0230 2.44 Shallow Concentrated Flow, Lawn Unpaved Kv= 16.1 fps 5.3 188 Total

24-223 DRAINAGE DESIGN-PROPOSED-2026-03-30 NOAA 24-hr D 10-Year-2050 Rainfall=6.37", P2=4.09" Prepared by Jarmel Kizel Architects & Engnrs Printed 3/30/2026 HydroCAD® 10.20-6a s/n 12607 © 2024 HydroCAD Software Solutions LLC Page 106 Subcatchment P3B-P: P3B PERVIOUS Hydrograph 0.1 Runoff 0.095 0.09 cfs 0.09 NOAA 24-hr D 0.085 0.08 10-Year-2050 Rainfall=6.37" 0.075 P2=4.09" 0.07 0.065 Runoff Area=1,881 sf 0.06 Runoff Volume=548 cf Flow (cfs) 0.055 0.05 Runoff Depth=3.50" 0.045 0.04 Flow Length=188' 0.035 Tc=5.3 min 0.03 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 10-Year-2050 Rainfall=6.37", P2=4.09" Prepared by Jarmel Kizel Architects & Engnrs Printed 3/30/2026 HydroCAD® 10.20-6a s/n 12607 © 2024 HydroCAD Software Solutions LLC Page 107 Summary for Subcatchment P3C: P3C- Roof Area Runoff = 0.35 cfs @ 12.00 hrs, Volume= 2,299 cf, Depth= 6.13" 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-2050 Rainfall=6.37", P2=4.09" 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) 0.8 52 0.0100 1.03 Sheet Flow, ROOF Smooth surfaces n= 0.011 P2= 4.09" 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 1.0 106 Total

24-223 DRAINAGE DESIGN-PROPOSED-2026-03-30 NOAA 24-hr D 10-Year-2050 Rainfall=6.37", P2=4.09" Prepared by Jarmel Kizel Architects & Engnrs Printed 3/30/2026 HydroCAD® 10.20-6a s/n 12607 © 2024 HydroCAD Software Solutions LLC Page 108 Subcatchment P3C: P3C- Roof Area Hydrograph 0.38 Runoff 0.35 cfs 0.36 0.34 NOAA 24-hr D 0.32 10-Year-2050 Rainfall=6.37" 0.3 0.28 P2=4.09" 0.26 Runoff Area=4,500 sf 0.24 Runoff Volume=2,299 cf Flow (cfs) 0.22 0.2 Runoff Depth=6.13" 0.18 0.16 Flow Length=106' 0.14 Tc=1.0 min 0.12 0.1 CN=98 0.08 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-2050 Rainfall=6.37", P2=4.09" Prepared by Jarmel Kizel Architects & Engnrs Printed 3/30/2026 HydroCAD® 10.20-6a s/n 12607 © 2024 HydroCAD Software Solutions LLC Page 109 Summary for Link 11L: Proposed Disturbed Inflow Area = 69,715 sf, 92.28% Impervious, Inflow Depth = 5.93" for 10-Year-2050 event Inflow = 5.26 cfs @ 12.01 hrs, Volume= 34,441 cf Primary = 5.26 cfs @ 12.01 hrs, Volume= 34,441 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 5.26 cfs Primary 5.26 cfs Inflow Area=69,715 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-2050 Rainfall=6.37", P2=4.09" Prepared by Jarmel Kizel Architects & Engnrs Printed 3/30/2026 HydroCAD® 10.20-6a s/n 12607 © 2024 HydroCAD Software Solutions LLC Page 110 Summary for Link 15L: TOTAL PROPOSED Inflow Area = 133,103 sf, 56.94% Impervious, Inflow Depth = 4.89" for 10-Year-2050 event Inflow = 7.98 cfs @ 12.04 hrs, Volume= 54,242 cf Primary = 7.98 cfs @ 12.04 hrs, Volume= 54,242 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 7.98 cfs Primary 8 7.98 cfs Inflow Area=133,103 sf 7 6 Flow (cfs) 5 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-2050 Rainfall=6.37", P2=4.09" Prepared by Jarmel Kizel Architects & Engnrs Printed 3/30/2026 HydroCAD® 10.20-6a s/n 12607 © 2024 HydroCAD Software Solutions LLC Page 111 Summary for Link P-DP 1: PROP DP 1 Inflow Area = 115,774 sf, 57.23% Impervious, Inflow Depth = 4.88" for 10-Year-2050 event Inflow = 6.87 cfs @ 12.04 hrs, Volume= 47,101 cf Primary = 6.87 cfs @ 12.04 hrs, Volume= 47,101 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 6.87 cfs Primary 7 6.87 cfs Inflow Area=115,774 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-2050 Rainfall=6.37", P2=4.09" Prepared by Jarmel Kizel Architects & Engnrs Printed 3/30/2026 HydroCAD® 10.20-6a s/n 12607 © 2024 HydroCAD Software Solutions LLC Page 112 Summary for Link P-DP 2: PROP DP 2 Inflow Area = 17,329 sf, 54.94% Impervious, Inflow Depth = 4.94" for 10-Year-2050 event Inflow = 1.12 cfs @ 12.02 hrs, Volume= 7,141 cf Primary = 1.12 cfs @ 12.02 hrs, Volume= 7,141 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 1.12 cfs Primary 1.12 cfs Inflow Area=17,329 sf 1 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)