2026 05 Storm Water Management Report rcd 5 6 2026

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

ed PE, smooth interior Subcatchment 10S: PDA #1 - Impervious (On-Site Conveyance) 5.0 381 Total Hydrograph Subcatchment 11S: PDA #1 - Pervious (On-Site Conveyance) 0.95 Runoff Hydrograph 0.87 cfs 0.9 0.85 NOAA 24-hr D 0.2 Runoff 0.18 cfs 0.8 2-Year-Projected Rainfall=4.09" 0.19 0.75 0.18 NOAA 24-hr D P2=4.09" 0.7 0.17 2-Year-Projected Rainfall=4.09" 0.65 Runoff Area=0.204 ac 0.16

0.16 P2=4.09" 0.6 Runoff Volume=0.066 af 0.15 0.14 Runoff Area=0.071 ac Flow (cfs) 0.55 Runoff Depth=3.85" 0.13 0.5 Runoff Volume=0.013 af Flow Length=419' 0.12 Flow (cfs) 0.45 0.11 Runoff Depth=2.12" 0.4 Tc=2.0 min 0.35 0.1 Flow Length=381' CN=98 0.09 0.3

CN=98 0.09 0.3 0.08 Tc=5.0 min 0.25 0.07 CN=80 0.2 0.06 0.15 0.05 0.1 0.04 0.05 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

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 23 HydroCAD® 10.20-7a s/n 08640 © 2025 HydroCAD Software Solutions LLC Page 24 Summary for Subcatchment 12S: PDA #2 - Impervious Summary for Subcatchment 13S: PDA #2 - Pervious Runoff = 0.07 cfs @ 12.10 hrs, Volume= 0.005 af, Depth= 3.85" Runoff = 0.07 cfs @ 12.11 hrs, Volume= 0.004 af, Depth= 2.12" Routed to Link 5L : POI #2 Routed to Link 5L : POI #2 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 0.017 98 Paved parking, HSG D 0.025 80 >75% Grass cover, Good, HSG D 0.017 100.00% Impervious Area

0.025 80 >75% Grass cover, Good, HSG D 0.017 100.00% Impervious Area 0.025 100.00% 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) 0.5 42 0.0260 1.45 Sheet Flow, A-B 1.7 8 0.0200 0.08 Sheet Flow, A-B Smooth surfaces n= 0.011 P2= 4.09" Grass: Dense n= 0.240 P2= 4.09" 0.3 58 0.0300 3.52 Shallow Concentrated Flow, B-C 0.1 6 0.0150 0.79 Sheet Flow, B-C Paved Kv= 20.3 fps Smooth surfaces n= 0.011 P2= 4.09" 0.8 100 Total 1.1 5 0.0200 0.07 Sheet Flow, C-D Grass: Dense n= 0.240 P2= 4.09" Subcatchment 12S: PDA #2 - Impervious 0.6 133 0.0290 3.46 Shallow Concentrated Flow, D-E Paved Kv= 20.3 fps

Paved Kv= 20.3 fps Hydrograph 3.5 152 Total 0.08 Runoff 0.07 cfs Subcatchment 13S: PDA #2 - Pervious 0.075 0.07 NOAA 24-hr D Hydrograph 0.065 2-Year-Projected Rainfall=4.09" 0.06 P2=4.09" 0.075 0.07 cfs Runoff 0.055 Runoff Area=0.017 ac 0.07 NOAA 24-hr D 0.05 Runoff Volume=0.005 af 0.065

0.065 2-Year-Projected Rainfall=4.09" Runoff Depth=3.85" Flow (cfs) 0.06 0.045 P2=4.09" 0.04 Flow Length=100' 0.055 Runoff Area=0.025 ac 0.035 Tc=0.8 min 0.05 Runoff Volume=0.004 af 0.03 CN=98 0.045 Runoff Depth=2.12" Flow (cfs) 0.025

Flow (cfs) 0.025 0.04 Flow Length=152' 0.02 0.035 Tc=3.5 min 0.015 0.03 CN=80 0.01 0.025 0.005 0.02 0 0.015 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 0.005