Stormwater Management Report Revised as of 01282026 4936 0314 8685 v2

24-223 DRAINAGE DESIGN-PROPOSED-UPDATE Prepared by Jarmel Kizel Architects & Engnrs Printed 1/28/2026 HydroCAD® 10.20-6a s/n 12607 © 2024 HydroCAD Software Solutions LLC Page 2 Area Listing (all nodes) Area CN Description (sq-ft) (subcatchment-numbers) 16,526 74 >75% Grass cover, Good, HSG C (P1-P, P3A-P, P3B-P) 1,240 74 >75% Grass offsite (P2) 4,040 98 DRIVE/SIDEWALK (P3A-IMP) 1,220 98 Impervious (P2) 1,506 71 Meadow, non-grazed, HSG C (P2) 53,037 98 Roof and Amenity Area (1S, P3C) 2,744 98 Roof-offsite (P2) 980 98 SIDEWALK AREA (P3B-IMP) 19,976 98 Uncovered Paved parking, HSG C (P1-I) 32,065 70 wooded (P2)

24-223 DRAINAGE DESIGN-PROPOSED-UPDATE Prepared by Jarmel Kizel Architects & Engnrs Printed 1/28/2026 HydroCAD® 10.20-6a s/n 12607 © 2024 HydroCAD Software Solutions LLC Page 3 Soil Listing (all nodes) Area Soil Subcatchment (sq-ft) Group Numbers 0 HSG A 0 HSG B 38,008 HSG C P1-I, P1-P, P2, P3A-P, P3B-P 0 HSG D 95,326 Other 1S, P2, P3A-IMP, P3B-IMP, P3C

24-223 DRAINAGE DESIGN-PROPOSED-UPDATE Prepared by Jarmel Kizel Architects & Engnrs Printed 1/28/2026 HydroCAD® 10.20-6a s/n 12607 © 2024 HydroCAD Software Solutions LLC Page 4 Ground Covers (all nodes) HSG-A HSG-B HSG-C HSG-D Other Total Ground Subcatchment (sq-ft) (sq-ft) (sq-ft) (sq-ft) (sq-ft) (sq-ft) Cover Numbers 0 0 16,526 0 0 16,526 >75% Grass cover, Good P1-P, P3A-P, P3B-P 0 0 0 0 1,240 1,240 >75% Grass offsite P2 0 0 0 0 4,040 4,040 DRIVE/SIDEWALK P3A-IMP 0 0 0 0 1,220 1,220 Impervious P2 0 0 1,506 0 0 1,506 Meadow, non-grazed P2 0 0 0 0 53,037 53,037 Roof and Amenity Area 1S, P3C 0 0 0 0 2,744 2,744 Roof-offsite P2 0 0 0 0 980 980 SIDEWALK AREA P3B-IMP 0 0 19,976 0 0 19,976 Uncovered Paved parking P1-I 0 0 0 0 32,065 32,065 wooded P2

24-223 DRAINAGE DESIGN-PROPOSED-UPDATE NOAA 24-hr D 2-Year-2020 Rainfall=3.47", P2=3.47" Prepared by Jarmel Kizel Architects & Engnrs Printed 1/28/2026 HydroCAD® 10.20-6a s/n 12607 © 2024 HydroCAD Software Solutions LLC Page 5 Summary for Subcatchment 1S: Roof Runoff = 2.04 cfs @ 12.01 hrs, Volume= 13,091 cf, Depth= 3.24" Routed to Link 11L : Proposed Disturbed Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-36.00 hrs, dt= 0.50 hrs NOAA 24-hr D 2-Year-2020 Rainfall=3.47", P2=3.47" Area (sf) CN Description * 48,537 98 Roof and Amenity Area 48,537 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 0.7 53 0.0200 1.26 Sheet Flow, ROOF Smooth surfaces n= 0.011 P2= 3.47" 0.5 196 0.0200 6.95 5.46 Pipe Channel, 12 ROOF DRAIN 12.0" Round Area= 0.8 sf Perim= 3.1' r= 0.25' n= 0.012 0.3 217 0.0424 11.74 14.41 Pipe Channel, 15 15.0" Round Area= 1.2 sf Perim= 3.9' r= 0.31' n= 0.012 1.5 466 Total

24-223 DRAINAGE DESIGN-PROPOSED-UPDATE NOAA 24-hr D 2-Year-2020 Rainfall=3.47", P2=3.47" Prepared by Jarmel Kizel Architects & Engnrs Printed 1/28/2026 HydroCAD® 10.20-6a s/n 12607 © 2024 HydroCAD Software Solutions LLC Page 6 Subcatchment 1S: Roof Hydrograph Runoff 2.04 cfs 2 NOAA 24-hr D 2-Year-2020 Rainfall=3.47" P2=3.47" Runoff Area=48,537 sf Runoff Volume=13,091 cf Flow (cfs) Runoff Depth=3.24" 1 Flow Length=466' Tc=1.5 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 31 32 33 34 35 36 Time (hours)

24-223 DRAINAGE DESIGN-PROPOSED-UPDATE NOAA 24-hr D 2-Year-2020 Rainfall=3.47", P2=3.47" Prepared by Jarmel Kizel Architects & Engnrs Printed 1/28/2026 HydroCAD® 10.20-6a s/n 12607 © 2024 HydroCAD Software Solutions LLC Page 7 Summary for Subcatchment P1-I: P1 IMPERVIOUS PARKING Runoff = 0.84 cfs @ 12.01 hrs, Volume= 5,388 cf, Depth= 3.24" Routed to Link 11L : Proposed Disturbed Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-36.00 hrs, dt= 0.50 hrs NOAA 24-hr D 2-Year-2020 Rainfall=3.47", P2=3.47" Area (sf) CN Description * 19,976 98 Uncovered Paved parking, HSG C 19,976 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 1.5 100 0.0150 1.12 Sheet Flow, sheet flow Parking area n= 0.013 P2= 3.47" 0.9 127 0.0150 2.49 Shallow Concentrated Flow, parking area Paved Kv= 20.3 fps 0.3 198 0.0449 12.08 14.83 Pipe Channel, Pipe flow 15.0" Round Area= 1.2 sf Perim= 3.9' r= 0.31' n= 0.012 2.7 425 Total

24-223 DRAINAGE DESIGN-PROPOSED-UPDATE NOAA 24-hr D 2-Year-2020 Rainfall=3.47", P2=3.47" Prepared by Jarmel Kizel Architects & Engnrs Printed 1/28/2026 HydroCAD® 10.20-6a s/n 12607 © 2024 HydroCAD Software Solutions LLC Page 8 Subcatchment P1-I: P1 IMPERVIOUS PARKING Hydrograph Runoff 0.9 0.84 cfs 0.85 0.8 NOAA 24-hr D 0.75 2-Year-2020 Rainfall=3.47" 0.7 0.65 P2=3.47" 0.6 Runoff Area=19,976 sf 0.55 Runoff Volume=5,388 cf Flow (cfs) 0.5 0.45 Runoff Depth=3.24" 0.4 0.35 Flow Length=425' 0.3 Tc=2.7 min 0.25 0.2 CN=98 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 31 32 33 34 35 36 Time (hours)

24-223 DRAINAGE DESIGN-PROPOSED-UPDATE NOAA 24-hr D 2-Year-2020 Rainfall=3.47", P2=3.47" Prepared by Jarmel Kizel Architects & Engnrs Printed 1/28/2026 HydroCAD® 10.20-6a s/n 12607 © 2024 HydroCAD Software Solutions LLC Page 9 Summary for Subcatchment P1-P: P1 PERVIOUS Runoff = 0.12 cfs @ 12.17 hrs, Volume= 886 cf, Depth= 1.22" Routed to Link 11L : Proposed Disturbed Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-36.00 hrs, dt= 0.50 hrs NOAA 24-hr D 2-Year-2020 Rainfall=3.47", P2=3.47" Area (sf) CN Description 8,717 74 >75% Grass cover, Good, HSG C 8,717 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 10.1 100 0.0430 0.17 Sheet Flow, Grass: Dense n= 0.240 P2= 3.47" 0.1 44 0.0470 12.36 15.17 Pipe Channel, Yard Inlet 15.0" Round Area= 1.2 sf Perim= 3.9' r= 0.31' n= 0.012 0.2 325 0.0450 31.77 898.40 Pipe Channel, 72" Culvert 72.0" Round Area= 28.3 sf Perim= 18.8' r= 1.50' n= 0.013 10.4 469 Total

24-223 DRAINAGE DESIGN-PROPOSED-UPDATE NOAA 24-hr D 2-Year-2020 Rainfall=3.47", P2=3.47" Prepared by Jarmel Kizel Architects & Engnrs Printed 1/28/2026 HydroCAD® 10.20-6a s/n 12607 © 2024 HydroCAD Software Solutions LLC Page 10 Subcatchment P1-P: P1 PERVIOUS Hydrograph 0.13 Runoff 0.125 0.12 cfs 0.12 0.115 NOAA 24-hr D 0.11 0.105 2-Year-2020 Rainfall=3.47" 0.1 0.095 0.09 P2=3.47" 0.085 0.08 Runoff Area=8,717 sf 0.075 Runoff Volume=886 cf Flow (cfs) 0.07 0.065 0.06 Runoff Depth=1.22" 0.055 0.05 Flow Length=469' 0.045 0.04 Tc=10.4 min 0.035 0.03 CN=74 0.025 0.02 0.015 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 31 32 33 34 35 36

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 31 32 33 34 35 36 Time (hours)