2026 05 Storm Water Management Report rcd 5 6 2026

2026-04 Proposed & Existing Conditi NOAA 24-hr D 2-Year-Current Rainfall=3.47", P2=3.47" 2026-04 Proposed & Existing CondiNOAA 24-hr D 2-Year-Projected Rainfall=4.09", P2=4.09" Prepared by Dynamic Engineering Printed 5/5/2026 Prepared by Dynamic Engineering Printed 5/5/2026 HydroCAD® 10.20-7a s/n 08640 © 2025 HydroCAD Software Solutions LLC Page 17 HydroCAD® 10.20-7a s/n 08640 © 2025 HydroCAD Software Solutions LLC Page 18 Summary for Link 6L: POI #3 Summary for Subcatchment 7S: Proposed Roof Inflow Area = 0.076 ac, 0.00% Impervious, Inflow Depth = 1.61" for 2-Year-Current event Runoff = 0.61 cfs @ 12.10 hrs, Volume= 0.046 af, Depth= 3.85" Inflow = 0.13 cfs @ 12.17 hrs, Volume= 0.010 af Routed to Pond 1P : UG BASIN Primary = 0.13 cfs @ 12.17 hrs, Volume= 0.010 af, Atten= 0%, Lag= 0.0 min Routed to nonexistent node 18L Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.001 hrs NOAA 24-hr D 2-Year-Projected Rainfall=4.09", P2=4.09" Primary outflow = Inflow, Time Span= 0.00-72.00 hrs, dt= 0.001 hrs Area (ac) CN Description Link 6L: POI #3

Area (ac) CN Description Link 6L: POI #3 0.142 98 Roofs, HSG D Hydrograph 0.142 100.00% Impervious Area Inflow Tc Length Slope Velocity Capacity Description 0.13 cfs Primary 0.14 0.13 cfs (min) (feet) (ft/ft) (ft/sec) (cfs) 0.13 Inflow Area=0.076 ac 1.0 Direct Entry, 0.12 0.11 Subcatchment 7S: Proposed Roof 0.1 Hydrograph 0.09 Runoff 0.65 0.61 cfs Flow (cfs) 0.08 0.07

0.65 0.61 cfs Flow (cfs) 0.08 0.07 0.6 NOAA 24-hr D 0.06 0.55 2-Year-Projected Rainfall=4.09" 0.05 0.5 P2=4.09" 0.04 0.45 Runoff Area=0.142 ac 0.03 0.4 Runoff Volume=0.046 af Flow (cfs) 0.02 Runoff Depth=3.85" 0.35 0.01

0.35 0.01 Tc=1.0 min 0.3 0 CN=98 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 0.25 Time (hours) 0.2 0.15 0.1 0.05 0 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours)

2026-04 Proposed & Existing CondiNOAA 24-hr D 2-Year-Projected Rainfall=4.09", P2=4.09" 2026-04 Proposed & Existing CondiNOAA 24-hr D 2-Year-Projected Rainfall=4.09", P2=4.09" Prepared by Dynamic Engineering Printed 5/5/2026 Prepared by Dynamic Engineering Printed 5/5/2026 HydroCAD® 10.20-7a s/n 08640 © 2025 HydroCAD Software Solutions LLC Page 19 HydroCAD® 10.20-7a s/n 08640 © 2025 HydroCAD Software Solutions LLC Page 20 Summary for Subcatchment 8S: PDA #1 - Impervious to Bio Summary for Subcatchment 9S: PDA #1 - Pervious to Bio Runoff = 0.33 cfs @ 12.10 hrs, Volume= 0.025 af, Depth= 3.85" Runoff = 0.18 cfs @ 12.12 hrs, Volume= 0.012 af, Depth= 2.12" Routed to Pond 2P : BIO BASIN Routed to Pond 2P : BIO BASIN Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.001 hrs Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.001 hrs NOAA 24-hr D 2-Year-Projected Rainfall=4.09", P2=4.09" NOAA 24-hr D 2-Year-Projected Rainfall=4.09", P2=4.09" Area (ac) CN Description Area (ac) CN Description 0.078 98 Paved parking, HSG D 0.068 80 >75% Grass cover, Good, HSG D 0.078 100.00% Impervious Area

0.068 80 >75% Grass cover, Good, HSG D 0.078 100.00% Impervious Area 0.068 100.00% Pervious Area Tc Length Slope Velocity Capacity Description Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) (min) (feet) (ft/ft) (ft/sec) (cfs) 0.4 42 0.0326 1.59 Sheet Flow, A-B 4.8 45 0.0450 0.16 Sheet Flow, A-B Smooth surfaces n= 0.011 P2= 4.09" Grass: Dense n= 0.240 P2= 4.09" 0.1 18 0.1180 5.53 Shallow Concentrated Flow, B-C (RIP-RAP) 0.2 29 0.0148 2.47 Shallow Concentrated Flow, B-C Unpaved Kv= 16.1 fps Paved Kv= 20.3 fps 0.5 60 Total 0.1 18 0.1180 5.53 Shallow Concentrated Flow, C-D (RIP-RAP) Unpaved Kv= 16.1 fps Subcatchment 8S: PDA #1 - Impervious to Bio 5.1 92 Total Hydrograph

Hydrograph Subcatchment 9S: PDA #1 - Pervious to Bio Runoff Hydrograph 0.36 0.33 cfs 0.34 NOAA 24-hr D Runoff 0.32 0.19 0.18 cfs 0.3 2-Year-Projected Rainfall=4.09" 0.18 NOAA 24-hr D 0.28 P2=4.09" 0.17 0.26 0.16 2-Year-Projected Rainfall=4.09" Runoff Area=0.078 ac 0.15 0.24 P2=4.09" 0.22

P2=4.09" 0.22 Runoff Volume=0.025 af 0.14 Runoff Area=0.068 ac Flow (cfs) 0.2 Runoff Depth=3.85" 0.13 0.18 Flow Length=60' 0.12 Runoff Volume=0.012 af Flow (cfs) 0.11 0.16 Tc=0.5 min Runoff Depth=2.12" 0.1 0.14 CN=98 0.09 Flow Length=92' 0.12

Flow Length=92' 0.12 0.08 Tc=5.1 min 0.1 0.08 0.07 CN=80 0.06 0.06 0.05 0.04 0.04 0.02 0.03 0 0.02 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) 0.01 0 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours)

2026-04 Proposed & Existing CondiNOAA 24-hr D 2-Year-Projected Rainfall=4.09", P2=4.09" 2026-04 Proposed & Existing CondiNOAA 24-hr D 2-Year-Projected Rainfall=4.09", P2=4.09" Prepared by Dynamic Engineering Printed 5/5/2026 Prepared by Dynamic Engineering Printed 5/5/2026 HydroCAD® 10.20-7a s/n 08640 © 2025 HydroCAD Software Solutions LLC Page 21 HydroCAD® 10.20-7a s/n 08640 © 2025 HydroCAD Software Solutions LLC Page 22 Summary for Subcatchment 10S: PDA #1 - Impervious (On-Site Conveyance) Summary for Subcatchment 11S: PDA #1 - Pervious (On-Site Conveyance) Runoff = 0.87 cfs @ 12.10 hrs, Volume= 0.066 af, Depth= 3.85" Runoff = 0.18 cfs @ 12.13 hrs, Volume= 0.013 af, Depth= 2.12" Routed to Link 4L : POI #1 Routed to Link 4L : POI #1 Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.001 hrs Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.001 hrs NOAA 24-hr D 2-Year-Projected Rainfall=4.09", P2=4.09" NOAA 24-hr D 2-Year-Projected Rainfall=4.09", P2=4.09" Area (ac) CN Description Area (ac) CN Description 0.204 98 Paved parking, HSG D 0.071 80 >75% Grass cover, Good, HSG D 0.204 100.00% Impervious Area