Stormwater Management Report 03302026

eak runoff rates and volumes for stormwater leaving the site for the 2, 10, and 100-year storm events at each design point respectively. It is our opinion that the calculations provided and summarized above demonstrate compliance with the Township ordinance 25-29 Stormwater Control. 8

APPENDIX A EXISTING DRAINAGE CALCULATIONS

E1A E1A DISTURBED/IMPERVIOUS E2-P 8L E2A PERVIOUS EXISTING DISTURBED E1C E2-IMP E1C Pervious-w-offsite-Undisturbed E2A IMPERVIOUS E-DP 1 E-DP 2 E2B-IMP EXIST DP 1 EXIST DP 2 E2B IMPERVIOUS E2B-P 9L E2B PERVIOUS TOTAL EXISTING Routing Diagram for 24-223 DRAINAGE DESIGN-EXISTING-2026-03-30 Subcat Reach Pond Link Prepared by Jarmel Kizel Architects & Engnrs, Printed 3/30/2026 HydroCAD® 10.20-6a s/n 12607 © 2024 HydroCAD Software Solutions LLC

24-223 DRAINAGE DESIGN-EXISTING-2026-03-30 Prepared by Jarmel Kizel Architects & Engnrs Printed 3/30/2026 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) 4,871 74 >75% Grass cover, Good, HSG C (E1C, E2-P, E2B-P) 1,220 98 Impervious-offsite (E1C) 2,721 71 Meadow, non-grazed, HSG C (E1C) 78,487 98 Paved parking, HSG C (E1A, E2-IMP, E2B-IMP) 708 98 Roof-offsite (E1C) 4,643 98 Roofs, HSG C (E2-IMP) 7,928 72 Woods/grass comb., Good, HSG C (E1C) 32,525 70 wooded (E1C)

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 3 Summary for Subcatchment E1A: E1A DISTURBED/IMPERVIOUS Runoff = 2.94 cfs @ 12.01 hrs, Volume= 18,851 cf, Depth= 3.24" 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 2-Year-2020 Rainfall=3.47", 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 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 4 Subcatchment E1A: E1A DISTURBED/IMPERVIOUS Hydrograph Runoff 2.94 cfs 3 NOAA 24-hr D 2-Year-2020 Rainfall=3.47" P2=3.47" 2 Runoff Area=69,893 sf Runoff Volume=18,851 cf Flow (cfs) Runoff Depth=3.24" Flow Length=439' 1 Tc=2.1 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 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 5 Summary for Subcatchment E1C: E1C Pervious-w-offsite-Undisturbed Runoff = 0.53 cfs @ 12.36 hrs, Volume= 4,253 cf, Depth= 1.10" 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 2-Year-2020 Rainfall=3.47", 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 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 6 Subcatchment E1C: E1C Pervious-w-offsite-Undisturbed Hydrograph Runoff 0.55 0.53 cfs 0.5 NOAA 24-hr D 2-Year-2020 Rainfall=3.47" 0.45 P2=3.47" 0.4 Runoff Area=46,342 sf 0.35 Runoff Volume=4,253 cf Flow (cfs) 0.3 Runoff Depth=1.10" 0.25 Flow Length=668' 0.2 Tc=13.6 min 0.15 CN=72 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 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 7 Summary for Subcatchment E2-IMP: E2A IMPERVIOUS Runoff = 0.51 cfs @ 12.01 hrs, Volume= 3,246 cf, Depth= 3.24" 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-2020 Rainfall=3.47", 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 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 8 Subcatchment E2-IMP: E2A IMPERVIOUS Hydrograph 0.55 Runoff 0.51 cfs 0.5 NOAA 24-hr D 0.45 2-Year-2020 Rainfall=3.47" 0.4 P2=3.47" Runoff Area=12,035 sf 0.35 Runoff Volume=3,246 cf Flow (cfs) 0.3 Runoff Depth=3.24" 0.25 Flow Length=435' 0.2 Slope=0.0550 '/' 0.15 Tc=2.0 min 0.1 CN=98 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)