Stormwater Management Report Feb 2026 resubmissionrcd 2 26 2026

2026-02 Proposed Conditions - AJ NOAA 24-hr D 100-Year-Current Rainfall=9.18", P2=3.47" Prepared by Dynamic Engineering Printed 2/16/2026 HydroCAD® 10.20-7a s/n 08640 © 2025 HydroCAD Software Solutions LLC Page 46 Summary for Subcatchment 7S: PDA #1 - Pervious to Bio Runoff = 0.39 cfs @ 12.13 hrs, Volume= 0.028 af, Depth= 6.74" 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 NOAA 24-hr D 100-Year-Current Rainfall=9.18", P2=3.47" Area (sf) CN Description 2,178 80 >75% Grass cover, Good, HSG D 2,178 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.2 45 0.0450 0.14 Sheet Flow, A-B Grass: Dense n= 0.240 P2= 3.47" 0.2 29 0.0148 2.47 Shallow Concentrated Flow, B-C Paved Kv= 20.3 fps 0.1 18 0.1180 5.53 Shallow Concentrated Flow, C-D (RIP-RAP) Unpaved Kv= 16.1 fps 5.5 92 Total Subcatchment 7S: PDA #1 - Pervious to Bio Hydrograph Runoff 0.42 0.39 cfs 0.4 0.38 NOAA 24-hr D 0.36 100-Year-Current Rainfall=9.18" 0.34 0.32 P2=3.47" 0.3 Runoff Area=2,178 sf 0.28

P2=3.47" 0.3 Runoff Area=2,178 sf 0.28 Runoff Volume=0.028 af 0.26 Runoff Depth=6.74" Flow (cfs) 0.24 0.22 Flow Length=92' 0.2 0.18 Tc=5.5 min 0.16 CN=80 0.14 0.12 0.1 0.08 0.06 0.04 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)

2026-02 Proposed Conditions - AJ NOAA 24-hr D 100-Year-Current Rainfall=9.18", P2=3.47" Prepared by Dynamic Engineering Printed 2/16/2026 HydroCAD® 10.20-7a s/n 08640 © 2025 HydroCAD Software Solutions LLC Page 47 Summary for Pond 1P: UG BASIN Inflow Area = 0.142 ac,100.00% Impervious, Inflow Depth = 8.94" for 100-Year-Current event Inflow = 1.37 cfs @ 12.10 hrs, Volume= 0.106 af Outflow = 0.95 cfs @ 12.11 hrs, Volume= 0.106 af, Atten= 31%, Lag= 0.8 min Primary = 0.95 cfs @ 12.11 hrs, Volume= 0.106 af Routed to Link 2L : POI #1 Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.001 hrs Peak Elev= 620.83' @ 12.11 hrs Surf.Area= 0.005 ac Storage= 0.017 af Plug-Flow detention time= 11.1 min calculated for 0.106 af (100% of inflow) Center-of-Mass det. time= 11.1 min ( 746.7 - 735.7 ) Volume Invert Avail.Storage Storage Description #1 617.75' 0.020 af 48.0" Round Pipe Storage L= 70.0' Device Routing Invert Outlet Devices #1 Primary 617.75' 15.0" Round RCP_Round 15" L= 15.0' RCP, rounded edge headwall, Ke= 0.100 Inlet / Outlet Invert= 617.75' / 617.55' S= 0.0133 '/' Cc= 0.900 n= 0.012 Concrete pipe, finished, Flow Area= 1.23 sf #2 Device 1 617.75' 3.0" Vert. Orifice C= 0.600 Limited to weir flow at low heads #3 Device 1 620.25' 6.0" Vert. Orifice C= 0.600 Limited to weir flow at low heads #4 Device 1 621.45' 4.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) Primary OutFlow Max=0.95 cfs @ 12.11 hrs HW=620.83' (Free Discharge) 1=RCP_Round 15" (Passes 0.95 cfs of 11.87 cfs potential flow) 2=Orifice (Orifice Controls 0.41 cfs @ 8.28 fps) 3=Orifice (Orifice Controls 0.54 cfs @ 2.77 fps) 4=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs)

2026-02 Proposed Conditions - AJ NOAA 24-hr D 100-Year-Current Rainfall=9.18", P2=3.47" Prepared by Dynamic Engineering Printed 2/16/2026 HydroCAD® 10.20-7a s/n 08640 © 2025 HydroCAD Software Solutions LLC Page 48 Pond 1P: UG BASIN Hydrograph Inflow 1.37 cfs Primary Inflow Area=0.142 ac Peak Elev=620.83' 0.95 cfs Storage=0.017 af 1 Flow (cfs) 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)

2026-02 Proposed Conditions - AJ NOAA 24-hr D 100-Year-Current Rainfall=9.18", P2=3.47" Prepared by Dynamic Engineering Printed 2/16/2026 HydroCAD® 10.20-7a s/n 08640 © 2025 HydroCAD Software Solutions LLC Page 49 Summary for Pond 2P: BIO BASIN Inflow Area = 0.140 ac, 64.29% Impervious, Inflow Depth = 8.15" for 100-Year-Current event Inflow = 1.24 cfs @ 12.10 hrs, Volume= 0.095 af Outflow = 0.85 cfs @ 12.11 hrs, Volume= 0.087 af, Atten= 31%, Lag= 0.6 min Primary = 0.85 cfs @ 12.11 hrs, Volume= 0.087 af Routed to Link 2L : POI #1 Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.001 hrs Peak Elev= 623.54' @ 12.11 hrs Surf.Area= 784 sf Storage= 818 cf Plug-Flow detention time= 105.1 min calculated for 0.087 af (91% of inflow) Center-of-Mass det. time= 55.7 min ( 811.2 - 755.5 ) Volume Invert Avail.Storage Storage Description #1 622.00' 1,219 cf Custom Stage Data (Prismatic)Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 622.00 323 0 0 623.00 577 450 450 624.00 960 769 1,219 Device Routing Invert Outlet Devices #1 Primary 619.11' 15.0" Round Culvert L= 35.0' RCP, rounded edge headwall, Ke= 0.100 Inlet / Outlet Invert= 619.11' / 618.93' S= 0.0051 '/' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 1.23 sf #2 Device 1 622.86' 0.6' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #3 Device 1 623.70' 48.0" x 48.0" Horiz. Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.85 cfs @ 12.11 hrs HW=623.54' (Free Discharge) 1=Culvert (Passes 0.85 cfs of 13.04 cfs potential flow) 2=Sharp-Crested Rectangular Weir (Weir Controls 0.85 cfs @ 2.70 fps) 3=Grate ( Controls 0.00 cfs)

2026-02 Proposed Conditions - AJ NOAA 24-hr D 100-Year-Current Rainfall=9.18", P2=3.47" Prepared by Dynamic Engineering Printed 2/16/2026 HydroCAD® 10.20-7a s/n 08640 © 2025 HydroCAD Software Solutions LLC Page 50 Pond 2P: BIO BASIN Hydrograph Inflow 1.24 cfs Primary Inflow Area=0.140 ac Peak Elev=623.54' 1 0.85 cfs Storage=818 cf Flow (cfs) 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)

2026-02 Proposed Conditions - AJ NOAA 24-hr D 100-Year-Current Rainfall=9.18", P2=3.47" Prepared by Dynamic Engineering Printed 2/16/2026 HydroCAD® 10.20-7a s/n 08640 © 2025 HydroCAD Software Solutions LLC Page 51 Summary for Link 2L: POI #1 Inflow Area = 0.637 ac, 68.48% Impervious, Inflow Depth = 8.09" for 100-Year-Current event Inflow = 4.89 cfs @ 12.11 hrs, Volume= 0.429 af Primary = 4.89 cfs @ 12.11 hrs, Volume= 0.429 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-72.00 hrs, dt= 0.001 hrs Link 2L: POI #1 Hydrograph Inflow 4.89 cfs Primary 4.89 cfs 5 Inflow Area=0.637 ac 4 Flow (cfs) 3 2 1 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)

2026-02 Proposed Conditions - NOAA 24-hr D 100-Year-Projected Rainfall=11.52", P2=4.09" Prepared by Dynamic Engineering Printed 2/16/2026 HydroCAD® 10.20-7a s/n 08640 © 2025 HydroCAD Software Solutions LLC Page 52 Summary for Subcatchment 3S: Proposed Roof Runoff = 1.73 cfs @ 12.10 hrs, Volume= 0.134 af, Depth=11.28" Routed to Pond 1P : UG BASIN 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 100-Year-Projected Rainfall=11.52", P2=4.09" Area (sf) CN Description 6,205 98 Roofs, HSG B 6,205 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 1.0 Direct Entry, Subcatchment 3S: Proposed Roof Hydrograph Runoff 1.73 cfs NOAA 24-hr D 100-Year-Projected Rainfall=11.52" P2=4.09" Runoff Area=6,205 sf Runoff Volume=0.134 af Runoff Depth=11.28" Flow (cfs) 1 Tc=1.0 min

Tc=1.0 min 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)

2026-02 Proposed Conditions - NOAA 24-hr D 100-Year-Projected Rainfall=11.52", P2=4.09" Prepared by Dynamic Engineering Printed 2/16/2026 HydroCAD® 10.20-7a s/n 08640 © 2025 HydroCAD Software Solutions LLC Page 53 Summary for Subcatchment 4S: PDA #1 - Undetained Impervious Runoff = 2.47 cfs @ 12.10 hrs, Volume= 0.191 af, Depth=11.28" Routed to Link 2L : POI #1 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 100-Year-Projected Rainfall=11.52", P2=4.09" Area (sf) CN Description 8,866 98 Paved parking, HSG D 8,866 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 1.0 93 0.0188 1.50 Sheet Flow, A-B Smooth surfaces n= 0.011 P2= 4.09" 1.0 326 0.0115 5.64 6.93 Pipe Channel, B-C 15.0" Round Area= 1.2 sf Perim= 3.9' r= 0.31' n= 0.013 Corrugated PE, smooth interior 2.0 419 Total Subcatchment 4S: PDA #1 - Undetained Impervious Hydrograph Runoff 2.47 cfs NOAA 24-hr D 100-Year-Projected Rainfall=11.52" P2=4.09" 2 Runoff Area=8,866 sf Runoff Volume=0.191 af