Stormwater Management Report 03302026

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 67 Summary for Link P-DP 1: PROP DP 1 Inflow Area = 115,774 sf, 57.23% Impervious, Inflow Depth = 7.53" for 100-Year-2020 event Inflow = 10.42 cfs @ 12.04 hrs, Volume= 72,660 cf Primary = 10.42 cfs @ 12.04 hrs, Volume= 72,660 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 10.42 cfs Primary 11 10.42 cfs Inflow Area=115,774 sf 10 9 8 7 Flow (cfs) 6 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 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 68 Summary for Link P-DP 2: PROP DP 2 Inflow Area = 17,329 sf, 54.94% Impervious, Inflow Depth = 7.61" for 100-Year-2020 event Inflow = 1.71 cfs @ 12.02 hrs, Volume= 10,992 cf Primary = 1.71 cfs @ 12.02 hrs, Volume= 10,992 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 1.71 cfs Primary 1.71 cfs Inflow Area=17,329 sf Flow (cfs) 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 2-Year-2050 Rainfall=4.09", 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 69 Summary for Subcatchment 1S: Roof Runoff = 1.99 cfs @ 12.01 hrs, Volume= 12,862 cf, Depth= 3.85" 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 2-Year-2050 Rainfall=4.09", P2=4.09" 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) 0.6 53 0.0200 1.37 Sheet Flow, ROOF Smooth surfaces n= 0.011 P2= 4.09" 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 1.4 466 Total

24-223 DRAINAGE DESIGN-PROPOSED-2026-03-30 NOAA 24-hr D 2-Year-2050 Rainfall=4.09", 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 70 Subcatchment 1S: Roof Hydrograph Runoff 1.99 cfs 2 NOAA 24-hr D 2-Year-2050 Rainfall=4.09" P2=4.09" Runoff Area=40,040 sf Runoff Volume=12,862 cf Flow (cfs) 1 Runoff Depth=3.85" Flow Length=466' Tc=1.4 min CN=98 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-2050 Rainfall=4.09", 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 71 Summary for Subcatchment P1-I: P1 IMPERVIOUS PARKING Runoff = 1.21 cfs @ 12.01 hrs, Volume= 7,805 cf, Depth= 3.85" 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 2-Year-2050 Rainfall=4.09", P2=4.09" Area (sf) CN Description * 24,295 98 Uncovered Paved parking, HSG C 24,295 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 1.4 100 0.0150 1.21 Sheet Flow, sheet flow Parking area n= 0.013 P2= 4.09" 0.9 127 0.0150 2.49 Shallow Concentrated Flow, parking area Paved Kv= 20.3 fps 0.3 198 0.0449 12.08 14.83 Pipe Channel, Pipe flow 15.0" Round Area= 1.2 sf Perim= 3.9' r= 0.31' n= 0.012 2.6 425 Total

24-223 DRAINAGE DESIGN-PROPOSED-2026-03-30 NOAA 24-hr D 2-Year-2050 Rainfall=4.09", 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 72 Subcatchment P1-I: P1 IMPERVIOUS PARKING Hydrograph Runoff 1.21 cfs NOAA 24-hr D 2-Year-2050 Rainfall=4.09" 1 P2=4.09" Runoff Area=24,295 sf Runoff Volume=7,805 cf Flow (cfs) Runoff Depth=3.85" Flow Length=425' Tc=2.6 min CN=98 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-2050 Rainfall=4.09", 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 73 Summary for Subcatchment P1-P: P1 PERVIOUS Runoff = 0.11 cfs @ 12.08 hrs, Volume= 745 cf, Depth= 1.66" 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 2-Year-2050 Rainfall=4.09", P2=4.09" Area (sf) CN Description 5,380 74 >75% Grass cover, Good, HSG C 5,380 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.7 83 0.0660 0.21 Sheet Flow, Grass: Dense n= 0.240 P2= 4.09" 0.1 36 0.0280 9.54 11.71 Pipe Channel, Yard Inlet 15.0" Round Area= 1.2 sf Perim= 3.9' r= 0.31' n= 0.012 0.2 325 0.0450 31.77 898.40 Pipe Channel, 72" Culvert 72.0" Round Area= 28.3 sf Perim= 18.8' r= 1.50' n= 0.013 7.0 444 Total

24-223 DRAINAGE DESIGN-PROPOSED-2026-03-30 NOAA 24-hr D 2-Year-2050 Rainfall=4.09", 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 74 Subcatchment P1-P: P1 PERVIOUS Hydrograph 0.125 Runoff 0.12 0.11 cfs 0.115 0.11 NOAA 24-hr D 0.105 0.1 2-Year-2050 Rainfall=4.09" 0.095 0.09 P2=4.09" 0.085 0.08 Runoff Area=5,380 sf 0.075 Runoff Volume=745 cf Flow (cfs) 0.07 0.065 0.06 Runoff Depth=1.66" 0.055 0.05 Flow Length=444' 0.045 0.04 Tc=7.0 min 0.035 0.03 CN=74 0.025 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

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-2050 Rainfall=4.09", 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 75 Summary for Subcatchment P2: P2 Pervious-w-offsite-Undisturbed Runoff = 0.72 cfs @ 12.27 hrs, Volume= 5,848 cf, Depth= 1.52" Routed to Link P-DP 1 : PROP DP 1 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-2050 Rainfall=4.09", P2=4.09" Area (sf) CN Description * 708 98 Roof-offsite * 1,220 98 Impervious-offsite 2,721 71 Meadow, non-grazed, HSG C * 32,255 70 wooded 1,240 74 >75% Grass cover, Good, HSG C * 7,915 72 Woods/grass comb., Good, HSG C 46,059 72 Weighted Average 44,131 95.81% Pervious Area 1,928 4.19% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 10.4 100 0.0900 0.16 Sheet Flow, sheet flow Woods: Light underbrush n= 0.400 P2= 4.09" 0.6 123 0.5000 3.54 Shallow Concentrated Flow, SC Woodland Kv= 5.0 fps 1.7 445 0.0470 4.40 Shallow Concentrated Flow, Parking lot Paved Kv= 20.3 fps 12.7 668 Total