Stormwater Management Report 03302026

24-223 DRAINAGE DESIGN-EXISTING-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 82 Summary for Link E-DP 2: EXIST DP 2 Inflow Area = 16,868 sf, 78.47% Impervious, Inflow Depth = 5.56" for 10-Year-2050 event Inflow = 1.21 cfs @ 12.01 hrs, Volume= 7,822 cf Primary = 1.21 cfs @ 12.01 hrs, Volume= 7,822 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 1.21 cfs Primary 1.21 cfs Inflow Area=16,868 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)

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 83 Summary for Subcatchment E1A: E1A DISTURBED/IMPERVIOUS Runoff = 9.88 cfs @ 12.01 hrs, Volume= 65,692 cf, Depth=11.28" Routed to Link 8L : EXISTING 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-2050 Rainfall=11.52", P2=4.09" Area (sf) CN Description 69,893 98 Paved parking, HSG C 69,893 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 0.7 100 0.0650 2.49 Sheet Flow, Parking lot Smooth surfaces n= 0.011 P2= 4.09" 1.4 339 0.0420 4.16 Shallow Concentrated Flow, Parking lot Paved Kv= 20.3 fps 2.1 439 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 84 Subcatchment E1A: E1A DISTURBED/IMPERVIOUS Hydrograph 11 Runoff 9.88 cfs 10 NOAA 24-hr D 9 100-Year-2050 Rainfall=11.52" 8 P2=4.09" Runoff Area=69,893 sf 7 Runoff Volume=65,692 cf Flow (cfs) 6 Runoff Depth=11.28" 5 Flow Length=439' 4 Tc=2.1 min CN=98 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 85 Summary for Subcatchment E1C: E1C Pervious-w-offsite-Undisturbed Runoff = 4.10 cfs @ 12.15 hrs, Volume= 30,458 cf, Depth= 7.89" Routed to Link E-DP 1 : EXIST 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 100-Year-2050 Rainfall=11.52", P2=4.09" Area (sf) CN Description * 708 98 Roof-offsite * 1,220 98 Impervious-offsite 2,721 71 Meadow, non-grazed, HSG C * 32,525 70 wooded 1,240 74 >75% Grass cover, Good, HSG C * 7,928 72 Woods/grass comb., Good, HSG C 46,342 72 Weighted Average 44,414 95.84% Pervious Area 1,928 4.16% 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

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 86 Subcatchment E1C: E1C Pervious-w-offsite-Undisturbed Hydrograph Runoff 4.10 cfs 4 NOAA 24-hr D 100-Year-2050 Rainfall=11.52" P2=4.09" 3 Runoff Area=46,342 sf Runoff Volume=30,458 cf Flow (cfs) Runoff Depth=7.89" Flow Length=668' 2 Tc=12.7 min CN=72 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 87 Summary for Subcatchment E2-IMP: E2A IMPERVIOUS Runoff = 1.70 cfs @ 12.01 hrs, Volume= 11,312 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 4,643 98 Roofs, HSG C 7,392 98 Paved parking, HSG C 12,035 98 Weighted Average 12,035 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 0.7 100 0.0550 2.33 Sheet Flow, Pavement Smooth surfaces n= 0.011 P2= 4.09" 1.2 335 0.0550 4.76 Shallow Concentrated Flow, shadow concentrate Paved Kv= 20.3 fps 1.9 435 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 88 Subcatchment E2-IMP: E2A IMPERVIOUS Hydrograph Runoff 1.70 cfs NOAA 24-hr D 100-Year-2050 Rainfall=11.52" P2=4.09" Runoff Area=12,035 sf Runoff Volume=11,312 cf Flow (cfs) 1 Runoff Depth=11.28" Flow Length=435' Slope=0.0550 '/' Tc=1.9 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-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 89 Summary for Subcatchment E2-P: E2A PERVIOUS Runoff = 0.23 cfs @ 12.03 hrs, Volume= 1,428 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 2,099 74 >75% Grass cover, Good, HSG C 2,099 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.6 100 0.0600 0.30 Sheet Flow, sheet flow Grass: Short n= 0.150 P2= 4.09" 0.1 29 0.0600 3.94 Shallow Concentrated Flow, Lawn Unpaved Kv= 16.1 fps 5.7 129 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 90 Subcatchment E2-P: E2A PERVIOUS Hydrograph 0.26 Runoff 0.25 0.23 cfs 0.24 0.23 NOAA 24-hr D 0.22 0.21 100-Year-2050 Rainfall=11.52" 0.2 0.19 P2=4.09" 0.18 Runoff Area=2,099 sf 0.17 0.16 Runoff Volume=1,428 cf 0.15 Flow (cfs) 0.14 Runoff Depth=8.17" 0.13 0.12 Flow Length=129' 0.11 Slope=0.0600 '/' 0.1 0.09 Tc=5.7 min 0.08 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

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)