Stormwater Management Report 03302026

24-223 DRAINAGE DESIGN-EXISTING-2026-03-30 NOAA 24-hr D 100-Year-2020 Rainfall=9.18", 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 37 Summary for Subcatchment E1C: E1C Pervious-w-offsite-Undisturbed Runoff = 2.91 cfs @ 12.20 hrs, Volume= 22,181 cf, Depth= 5.74" 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-2020 Rainfall=9.18", 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 100-Year-2020 Rainfall=9.18", 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 38 Subcatchment E1C: E1C Pervious-w-offsite-Undisturbed Hydrograph Runoff 2.91 cfs 3 NOAA 24-hr D 100-Year-2020 Rainfall=9.18" P2=3.47" Runoff Area=46,342 sf 2 Runoff Volume=22,181 cf Flow (cfs) Runoff Depth=5.74" Flow Length=668' Tc=13.6 min 1 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 100-Year-2020 Rainfall=9.18", 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 39 Summary for Subcatchment E2-IMP: E2A IMPERVIOUS Runoff = 1.35 cfs @ 12.01 hrs, Volume= 8,966 cf, Depth= 8.94" 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-2020 Rainfall=9.18", 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 100-Year-2020 Rainfall=9.18", 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 40 Subcatchment E2-IMP: E2A IMPERVIOUS Hydrograph Runoff 1.35 cfs NOAA 24-hr D 100-Year-2020 Rainfall=9.18" P2=3.47" 1 Runoff Area=12,035 sf Runoff Volume=8,966 cf Flow (cfs) Runoff Depth=8.94" Flow Length=435' Slope=0.0550 '/' Tc=2.0 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-2020 Rainfall=9.18", 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 41 Summary for Subcatchment E2-P: E2A PERVIOUS Runoff = 0.17 cfs @ 12.04 hrs, Volume= 1,048 cf, Depth= 5.99" 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-2020 Rainfall=9.18", 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 100-Year-2020 Rainfall=9.18", 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 42 Subcatchment E2-P: E2A PERVIOUS Hydrograph 0.19 Runoff 0.18 0.17 cfs 0.17 NOAA 24-hr D 0.16 0.15 100-Year-2020 Rainfall=9.18" 0.14 P2=3.47" 0.13 Runoff Area=2,099 sf 0.12 0.11 Runoff Volume=1,048 cf Flow (cfs) 0.1 Runoff Depth=5.99" 0.09 Flow Length=129' 0.08 0.07 Slope=0.0600 '/' 0.06 Tc=6.2 min 0.05 CN=74 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

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-2020 Rainfall=9.18", 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 43 Summary for Subcatchment E2B-IMP: E2B IMPERVIOUS Runoff = 0.14 cfs @ 12.00 hrs, Volume= 895 cf, Depth= 8.94" 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-2020 Rainfall=9.18", P2=3.47" 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 2.61 Sheet Flow, sidewalk Smooth surfaces n= 0.011 P2= 3.47" 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-2020 Rainfall=9.18", 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 44 Subcatchment E2B-IMP: E2B IMPERVIOUS Hydrograph 0.15 Runoff 0.14 0.14 cfs 0.13 NOAA 24-hr D 0.12 100-Year-2020 Rainfall=9.18" 0.11 P2=3.47" 0.1 Runoff Area=1,202 sf 0.09 Runoff Volume=895 cf Flow (cfs) 0.08 Runoff Depth=8.94" 0.07 Flow Length=188' 0.06 Tc=1.1 min 0.05 CN=98 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-2020 Rainfall=9.18", 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 45 Summary for Subcatchment E2B-P: E2B PERVIOUS Runoff = 0.13 cfs @ 12.04 hrs, Volume= 765 cf, Depth= 5.99" 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-2020 Rainfall=9.18", P2=3.47" 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) 5.2 100 0.0900 0.32 Sheet Flow, sheet flow Grass: Short n= 0.150 P2= 3.47" 0.6 88 0.0250 2.55 Shallow Concentrated Flow, Lawn Unpaved Kv= 16.1 fps 5.8 188 Total