2026 05 Storm Water Management Report rcd 5 6 2026

Tc=1.0 min 0.02 CN=98 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) 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 CondNOAA 24-hr D 10-Year-Projected Rainfall=6.37", P2=4.09" 2026-04 Proposed & Existing CondNOAA 24-hr D 10-Year-Projected Rainfall=6.37", 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 49 HydroCAD® 10.20-7a s/n 08640 © 2025 HydroCAD Software Solutions LLC Page 50 Summary for Subcatchment 8S: PDA #1 - Impervious to Bio Summary for Subcatchment 9S: PDA #1 - Pervious to Bio Runoff = 0.52 cfs @ 12.10 hrs, Volume= 0.040 af, Depth= 6.13" Runoff = 0.34 cfs @ 12.12 hrs, Volume= 0.023 af, Depth= 4.12" 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 10-Year-Projected Rainfall=6.37", P2=4.09" NOAA 24-hr D 10-Year-Projected Rainfall=6.37", 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

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 0.55 0.52 cfs NOAA 24-hr D Runoff 0.5 0.36 0.34 cfs 10-Year-Projected Rainfall=6.37" 0.34 0.45 P2=4.09" NOAA 24-hr D 0.32 0.4 Runoff Area=0.078 ac 0.3 10-Year-Projected Rainfall=6.37" Runoff Volume=0.040 af 0.28 P2=4.09" 0.35

0.28 P2=4.09" 0.35 Runoff Depth=6.13" 0.26 Runoff Area=0.068 ac Flow (cfs) 0.24 Runoff Volume=0.023 af 0.3 Flow Length=60' 0.22 Runoff Depth=4.12" Flow (cfs) 0.25 Tc=0.5 min 0.2 CN=98 0.18 Flow Length=92' 0.2 0.16 Tc=5.1 min 0.15 0.14

0.14 CN=80 0.12 0.1 0.1 0.08 0.05 0.06 0 0.04 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) 0.02 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 CondNOAA 24-hr D 10-Year-Projected Rainfall=6.37", P2=4.09" 2026-04 Proposed & Existing CondNOAA 24-hr D 10-Year-Projected Rainfall=6.37", 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 51 HydroCAD® 10.20-7a s/n 08640 © 2025 HydroCAD Software Solutions LLC Page 52 Summary for Subcatchment 10S: PDA #1 - Impervious (On-Site Conveyance) Summary for Subcatchment 11S: PDA #1 - Pervious (On-Site Conveyance) Runoff = 1.36 cfs @ 12.10 hrs, Volume= 0.104 af, Depth= 6.13" Runoff = 0.35 cfs @ 12.12 hrs, Volume= 0.024 af, Depth= 4.12" 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 10-Year-Projected Rainfall=6.37", P2=4.09" NOAA 24-hr D 10-Year-Projected Rainfall=6.37", 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

0.071 80 >75% Grass cover, Good, HSG D 0.204 100.00% Impervious Area 0.071 100.00% 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) 1.0 93 0.0188 1.50 Sheet Flow, A-B 3.5 20 0.0200 0.10 Sheet Flow, A-B Smooth surfaces n= 0.011 P2= 4.09" Grass: Dense n= 0.240 P2= 4.09" 1.0 326 0.0115 5.64 6.93 Pipe Channel, B-C 0.5 35 0.0200 1.26 Sheet Flow, B-C 15.0" Round Area= 1.2 sf Perim= 3.9' r= 0.31' Smooth surfaces n= 0.011 P2= 4.09" n= 0.013 Corrugated PE, smooth interior 1.0 326 0.0115 5.64 6.93 Pipe Channel, C-D 2.0 419 Total 15.0" Round Area= 1.2 sf Perim= 3.9' r= 0.31' n= 0.013 Corrugated PE, smooth interior Subcatchment 10S: PDA #1 - Impervious (On-Site Conveyance) 5.0 381 Total

Subcatchment 10S: PDA #1 - Impervious (On-Site Conveyance) 5.0 381 Total Hydrograph Subcatchment 11S: PDA #1 - Pervious (On-Site Conveyance) Runoff Hydrograph 1.36 cfs NOAA 24-hr D Runoff 0.38 0.35 cfs 10-Year-Projected Rainfall=6.37" 0.36 P2=4.09" 0.34 NOAA 24-hr D Runoff Area=0.204 ac 0.32 10-Year-Projected Rainfall=6.37" 1 Runoff Volume=0.104 af 0.3

0.3 P2=4.09" 0.28 Runoff Depth=6.13" Runoff Area=0.071 ac Flow (cfs) 0.26 Flow Length=419' 0.24 Runoff Volume=0.024 af Runoff Depth=4.12" Flow (cfs) 0.22 Tc=2.0 min CN=98 0.2 Flow Length=381' 0.18