Stormwater Management Report 03302026

24-223 DRAINAGE DESIGN-EXISTING-2026-03-30 NOAA 24-hr D 100-Year-2050 Rainfall=11.52", 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 91 Summary for Subcatchment E2B-IMP: E2B IMPERVIOUS Runoff = 0.17 cfs @ 12.00 hrs, Volume= 1,130 cf, Depth=11.28" Routed to Link E-DP 2 : EXIST 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 100-Year-2050 Rainfall=11.52", P2=4.09" Area (sf) CN Description 1,202 98 Paved parking, HSG C 1,202 100.00% 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 0.0250 3.21 Shallow Concentrated Flow, shadow concentrate Paved Kv= 20.3 fps 1.1 188 Total

24-223 DRAINAGE DESIGN-EXISTING-2026-03-30 NOAA 24-hr D 100-Year-2050 Rainfall=11.52", 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 92 Subcatchment E2B-IMP: E2B IMPERVIOUS Hydrograph 0.19 Runoff 0.18 0.17 cfs 0.17 NOAA 24-hr D 0.16 0.15 100-Year-2050 Rainfall=11.52" 0.14 P2=4.09" 0.13 Runoff Area=1,202 sf 0.12 Runoff Volume=1,130 cf 0.11 Flow (cfs) 0.1 Runoff Depth=11.28" 0.09 Flow Length=188' 0.08 Tc=1.1 min 0.07 CN=98 0.06 0.05 0.04 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 Time (hours)

24-223 DRAINAGE DESIGN-EXISTING-2026-03-30 NOAA 24-hr D 100-Year-2050 Rainfall=11.52", 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 93 Summary for Subcatchment E2B-P: E2B PERVIOUS Runoff = 0.17 cfs @ 12.03 hrs, Volume= 1,042 cf, Depth= 8.17" Routed to Link E-DP 2 : EXIST 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 100-Year-2050 Rainfall=11.52", P2=4.09" Area (sf) CN Description 1,532 74 >75% Grass cover, Good, HSG C 1,532 100.00% 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 0.0250 2.55 Shallow Concentrated Flow, Lawn Unpaved Kv= 16.1 fps 5.3 188 Total

24-223 DRAINAGE DESIGN-EXISTING-2026-03-30 NOAA 24-hr D 100-Year-2050 Rainfall=11.52", 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 94 Subcatchment E2B-P: E2B PERVIOUS Hydrograph 0.19 Runoff 0.18 0.17 cfs 0.17 NOAA 24-hr D 0.16 100-Year-2050 Rainfall=11.52" 0.15 0.14 P2=4.09" 0.13 Runoff Area=1,532 sf 0.12 Runoff Volume=1,042 cf 0.11 Flow (cfs) Runoff Depth=8.17" 0.1 0.09 Flow Length=188' 0.08 Tc=5.3 min 0.07 CN=74 0.06 0.05 0.04 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 Time (hours)

24-223 DRAINAGE DESIGN-EXISTING-2026-03-30 NOAA 24-hr D 100-Year-2050 Rainfall=11.52", 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 95 Summary for Link 8L: EXISTING DISTURBED Inflow Area = 69,893 sf,100.00% Impervious, Inflow Depth = 11.28" for 100-Year-2050 event Inflow = 9.88 cfs @ 12.01 hrs, Volume= 65,692 cf Primary = 9.88 cfs @ 12.01 hrs, Volume= 65,692 cf, Atten= 0%, Lag= 0.0 min Routed to Link E-DP 1 : EXIST DP 1 Primary outflow = Inflow, Time Span= 0.00-30.00 hrs, dt= 0.50 hrs Link 8L: EXISTING DISTURBED Hydrograph Inflow 11 9.88 cfs Primary 10 9.88 cfs Inflow Area=69,893 sf 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-EXISTING-2026-03-30 NOAA 24-hr D 100-Year-2050 Rainfall=11.52", 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 96 Summary for Link 9L: TOTAL EXISTING Inflow Area = 133,103 sf, 63.90% Impervious, Inflow Depth = 10.01" for 100-Year-2050 event Inflow = 16.13 cfs @ 12.03 hrs, Volume= 111,062 cf Primary = 16.13 cfs @ 12.03 hrs, Volume= 111,062 cf, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-30.00 hrs, dt= 0.50 hrs Link 9L: TOTAL EXISTING Hydrograph Inflow 18 Primary 16.13 cfs 17 16 16.13 cfs Inflow Area=133,103 sf 15 14 13 12 11 Flow (cfs) 10 9 8 7 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

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-EXISTING-2026-03-30 NOAA 24-hr D 100-Year-2050 Rainfall=11.52", 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 97 Summary for Link E-DP 1: EXIST DP 1 Inflow Area = 116,235 sf, 61.79% Impervious, Inflow Depth = 9.93" for 100-Year-2050 event Inflow = 13.86 cfs @ 12.04 hrs, Volume= 96,150 cf Primary = 13.86 cfs @ 12.04 hrs, Volume= 96,150 cf, Atten= 0%, Lag= 0.0 min Routed to Link 9L : TOTAL EXISTING Primary outflow = Inflow, Time Span= 0.00-30.00 hrs, dt= 0.50 hrs Link E-DP 1: EXIST DP 1 Hydrograph Inflow 13.86 cfs Primary 15 14 13.86 cfs Inflow Area=116,235 sf 13 12 11 10 9 Flow (cfs) 8 7 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-EXISTING-2026-03-30 NOAA 24-hr D 100-Year-2050 Rainfall=11.52", 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 98 Summary for Link E-DP 2: EXIST DP 2 Inflow Area = 16,868 sf, 78.47% Impervious, Inflow Depth = 10.61" for 100-Year-2050 event Inflow = 2.28 cfs @ 12.01 hrs, Volume= 14,912 cf Primary = 2.28 cfs @ 12.01 hrs, Volume= 14,912 cf, Atten= 0%, Lag= 0.0 min Routed to Link 9L : TOTAL EXISTING Primary outflow = Inflow, Time Span= 0.00-30.00 hrs, dt= 0.50 hrs Link E-DP 2: EXIST DP 2 Hydrograph Inflow 2.28 cfs Primary 2.28 cfs Inflow Area=16,868 sf 2 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)

APPENDIX B PROPOSED DRAINAGE CALCULATIONS