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 56 Subcatchment E2-IMP: E2A IMPERVIOUS Hydrograph 0.65 Runoff 0.60 cfs 0.6 NOAA 24-hr D 0.55 2-Year-2050 Rainfall=4.09" 0.5 P2=4.09" 0.45 Runoff Area=12,035 sf 0.4 Runoff Volume=3,866 cf Flow (cfs) 0.35 Runoff Depth=3.85" 0.3 Flow Length=435' 0.25 Slope=0.0550 '/' 0.2 Tc=1.9 min 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

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 57 Summary for Subcatchment E2-P: E2A PERVIOUS Runoff = 0.05 cfs @ 12.07 hrs, Volume= 291 cf, Depth= 1.66" 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 2-Year-2050 Rainfall=4.09", 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 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 58 Subcatchment E2-P: E2A PERVIOUS Hydrograph 0.05 Runoff 0.048 0.05 cfs 0.046 0.044 NOAA 24-hr D 0.042 0.04 2-Year-2050 Rainfall=4.09" 0.038 0.036 P2=4.09" 0.034 0.032 Runoff Area=2,099 sf 0.03 Runoff Volume=291 cf Flow (cfs) 0.028 0.026 Runoff Depth=1.66" 0.024 0.022 Flow Length=129' 0.02 0.018 Slope=0.0600 '/' 0.016 0.014 Tc=5.7 min 0.012 0.01 CN=74 0.008 0.006 0.004 0.002 0 0 1 2 3 4 5 6

CN=74 0.008 0.006 0.004 0.002 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 59 Summary for Subcatchment E2B-IMP: E2B IMPERVIOUS Runoff = 0.06 cfs @ 12.00 hrs, Volume= 386 cf, Depth= 3.85" 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 2-Year-2050 Rainfall=4.09", 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 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 60 Subcatchment E2B-IMP: E2B IMPERVIOUS Hydrograph 0.065 Runoff 0.06 cfs 0.06 NOAA 24-hr D 0.055 2-Year-2050 Rainfall=4.09" 0.05 P2=4.09" 0.045 Runoff Area=1,202 sf 0.04 Runoff Volume=386 cf Flow (cfs) 0.035 0.03 Runoff Depth=3.85" 0.025 Flow Length=188' 0.02 Tc=1.1 min 0.015 CN=98 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)

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 61 Summary for Subcatchment E2B-P: E2B PERVIOUS Runoff = 0.03 cfs @ 12.06 hrs, Volume= 212 cf, Depth= 1.66" 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 2-Year-2050 Rainfall=4.09", 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 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 62 Subcatchment E2B-P: E2B PERVIOUS Hydrograph 0.038 Runoff 0.036 0.03 cfs 0.034 NOAA 24-hr D 0.032 0.03 2-Year-2050 Rainfall=4.09" 0.028 0.026 P2=4.09" 0.024 Runoff Area=1,532 sf 0.022 Runoff Volume=212 cf Flow (cfs) 0.02 0.018 Runoff Depth=1.66" 0.016 0.014 Flow Length=188' 0.012 Tc=5.3 min 0.01 0.008 CN=74 0.006 0.004 0.002 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 63 Summary for Link 8L: EXISTING DISTURBED Inflow Area = 69,893 sf,100.00% Impervious, Inflow Depth = 3.85" for 2-Year-2050 event Inflow = 3.48 cfs @ 12.01 hrs, Volume= 22,453 cf Primary = 3.48 cfs @ 12.01 hrs, Volume= 22,453 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 3.48 cfs Primary 3.48 cfs Inflow Area=69,893 sf 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)