Stormwater Management Report 03302026

24-223 DRAINAGE DESIGN-EXISTING-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 64 Summary for Link 9L: TOTAL EXISTING Inflow Area = 133,103 sf, 63.90% Impervious, Inflow Depth = 2.98" for 2-Year-2050 event Inflow = 4.90 cfs @ 12.03 hrs, Volume= 33,091 cf Primary = 4.90 cfs @ 12.03 hrs, Volume= 33,091 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 4.90 cfs Primary 5 4.90 cfs Inflow Area=133,103 sf 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-EXISTING-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 65 Summary for Link E-DP 1: EXIST DP 1 Inflow Area = 116,235 sf, 61.79% Impervious, Inflow Depth = 2.93" for 2-Year-2050 event Inflow = 4.16 cfs @ 12.03 hrs, Volume= 28,336 cf Primary = 4.16 cfs @ 12.03 hrs, Volume= 28,336 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 4.16 cfs Primary 4.16 cfs Inflow Area=116,235 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-EXISTING-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 66 Summary for Link E-DP 2: EXIST DP 2 Inflow Area = 16,868 sf, 78.47% Impervious, Inflow Depth = 3.38" for 2-Year-2050 event Inflow = 0.74 cfs @ 12.01 hrs, Volume= 4,755 cf Primary = 0.74 cfs @ 12.01 hrs, Volume= 4,755 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 0.74 cfs Primary 0.8 0.75 0.74 cfs Inflow Area=16,868 sf 0.7 0.65 0.6 0.55 0.5 Flow (cfs) 0.45 0.4 0.35 0.3 0.25 0.2 0.15 0.1 0.05 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 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 67 Summary for Subcatchment E1A: E1A DISTURBED/IMPERVIOUS Runoff = 5.45 cfs @ 12.01 hrs, Volume= 35,712 cf, Depth= 6.13" 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 10-Year-2050 Rainfall=6.37", 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 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 68 Subcatchment E1A: E1A DISTURBED/IMPERVIOUS Hydrograph 6 Runoff 5.45 cfs NOAA 24-hr D 5 10-Year-2050 Rainfall=6.37" P2=4.09" 4 Runoff Area=69,893 sf Runoff Volume=35,712 cf Flow (cfs) 3 Runoff Depth=6.13" Flow Length=439' 2 Tc=2.1 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)

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 69 Summary for Subcatchment E1C: E1C Pervious-w-offsite-Undisturbed Runoff = 1.70 cfs @ 12.19 hrs, Volume= 12,738 cf, Depth= 3.30" 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 10-Year-2050 Rainfall=6.37", 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 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 70 Subcatchment E1C: E1C Pervious-w-offsite-Undisturbed Hydrograph Runoff 1.70 cfs NOAA 24-hr D 10-Year-2050 Rainfall=6.37" P2=4.09" Runoff Area=46,342 sf Runoff Volume=12,738 cf Flow (cfs) 1 Runoff Depth=3.30" Flow Length=668' Tc=12.7 min CN=72 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 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 71 Summary for Subcatchment E2-IMP: E2A IMPERVIOUS Runoff = 0.94 cfs @ 12.01 hrs, Volume= 6,149 cf, Depth= 6.13" 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 10-Year-2050 Rainfall=6.37", 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 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 72 Subcatchment E2-IMP: E2A IMPERVIOUS Hydrograph Runoff 1 0.94 cfs NOAA 24-hr D 10-Year-2050 Rainfall=6.37" P2=4.09" Runoff Area=12,035 sf Runoff Volume=6,149 cf Flow (cfs) Runoff Depth=6.13" 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 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 73 Summary for Subcatchment E2-P: E2A PERVIOUS Runoff = 0.10 cfs @ 12.05 hrs, Volume= 612 cf, Depth= 3.50" 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 10-Year-2050 Rainfall=6.37", 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