Stormwater Management Report 03302026

24-223 DRAINAGE DESIGN-EXISTING-2026-03-30 NOAA 24-hr D 2-Year-2020 Rainfall=3.47", 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 18 Summary for Link E-DP 2: EXIST DP 2 Inflow Area = 16,868 sf, 78.47% Impervious, Inflow Depth = 2.80" for 2-Year-2020 event Inflow = 0.61 cfs @ 12.01 hrs, Volume= 3,939 cf Primary = 0.61 cfs @ 12.01 hrs, Volume= 3,939 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 0.61 cfs Primary 0.65 0.6 0.61 cfs Inflow Area=16,868 sf 0.55 0.5 0.45 0.4 Flow (cfs) 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-2020 Rainfall=5.38", 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 19 Summary for Subcatchment E1A: E1A DISTURBED/IMPERVIOUS Runoff = 4.59 cfs @ 12.01 hrs, Volume= 29,953 cf, Depth= 5.14" 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-2020 Rainfall=5.38", P2=3.47" 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 2.30 Sheet Flow, Parking lot Smooth surfaces n= 0.011 P2= 3.47" 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-2020 Rainfall=5.38", 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 20 Subcatchment E1A: E1A DISTURBED/IMPERVIOUS Hydrograph 5 Runoff 4.59 cfs NOAA 24-hr D 4 10-Year-2020 Rainfall=5.38" P2=3.47" Runoff Area=69,893 sf 3 Runoff Volume=29,953 cf Flow (cfs) Runoff Depth=5.14" 2 Flow Length=439' 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-2020 Rainfall=5.38", 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 21 Summary for Subcatchment E1C: E1C Pervious-w-offsite-Undisturbed Runoff = 1.22 cfs @ 12.27 hrs, Volume= 9,633 cf, Depth= 2.49" 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-2020 Rainfall=5.38", P2=3.47" 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) 11.3 100 0.0900 0.15 Sheet Flow, sheet flow Woods: Light underbrush n= 0.400 P2= 3.47" 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 13.6 668 Total

24-223 DRAINAGE DESIGN-EXISTING-2026-03-30 NOAA 24-hr D 10-Year-2020 Rainfall=5.38", 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 22 Subcatchment E1C: E1C Pervious-w-offsite-Undisturbed Hydrograph Runoff 1.22 cfs NOAA 24-hr D 10-Year-2020 Rainfall=5.38" 1 P2=3.47" Runoff Area=46,342 sf Runoff Volume=9,633 cf Flow (cfs) Runoff Depth=2.49" Flow Length=668' Tc=13.6 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-2020 Rainfall=5.38", 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 23 Summary for Subcatchment E2-IMP: E2A IMPERVIOUS Runoff = 0.79 cfs @ 12.01 hrs, Volume= 5,158 cf, Depth= 5.14" 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-2020 Rainfall=5.38", P2=3.47" 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) 0.8 100 0.0550 2.15 Sheet Flow, Pavement Smooth surfaces n= 0.011 P2= 3.47" 1.2 335 0.0550 4.76 Shallow Concentrated Flow, shadow concentrate Paved Kv= 20.3 fps 2.0 435 Total

24-223 DRAINAGE DESIGN-EXISTING-2026-03-30 NOAA 24-hr D 10-Year-2020 Rainfall=5.38", 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 24 Subcatchment E2-IMP: E2A IMPERVIOUS Hydrograph Runoff 0.85 0.79 cfs 0.8 0.75 NOAA 24-hr D 0.7 10-Year-2020 Rainfall=5.38" 0.65 P2=3.47" 0.6 0.55 Runoff Area=12,035 sf Runoff Volume=5,158 cf Flow (cfs) 0.5 0.45 Runoff Depth=5.14" 0.4 0.35 Flow Length=435' 0.3 Slope=0.0550 '/' 0.25 Tc=2.0 min 0.2 0.15 CN=98 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

.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-2020 Rainfall=5.38", 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 25 Summary for Subcatchment E2-P: E2A PERVIOUS Runoff = 0.08 cfs @ 12.06 hrs, Volume= 467 cf, Depth= 2.67" 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-2020 Rainfall=5.38", P2=3.47" 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) 6.1 100 0.0600 0.27 Sheet Flow, sheet flow Grass: Short n= 0.150 P2= 3.47" 0.1 29 0.0600 3.94 Shallow Concentrated Flow, Lawn Unpaved Kv= 16.1 fps 6.2 129 Total

24-223 DRAINAGE DESIGN-EXISTING-2026-03-30 NOAA 24-hr D 10-Year-2020 Rainfall=5.38", 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 26 Subcatchment E2-P: E2A PERVIOUS Hydrograph Runoff 0.08 0.08 cfs 0.075 NOAA 24-hr D 0.07 10-Year-2020 Rainfall=5.38" 0.065 0.06 P2=3.47" 0.055 Runoff Area=2,099 sf 0.05 Runoff Volume=467 cf Flow (cfs) 0.045 0.04 Runoff Depth=2.67" 0.035 Flow Length=129' 0.03 Slope=0.0600 '/' 0.025 0.02 Tc=6.2 min 0.015 CN=74 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)