complete drainage report rev 9

POA-2 2024-05-12 HydroCad - Proposed POA 2B-1 NOAA 24-hr D 100-Year Rainfall=8.66" Prepared by Anderson Consulting Services HydroCAD® 10.20-5c s/n 06666 © 2023 HydroCAD Software Solutions LLC Printed 10/25/2024 Page 262 Subcatchment 53S: Basin 9 - Imp Hydrograph Runoff 3.12 cfs Flow (cfs) 3 2 1 NOAA 24-hr D 100-Year Rainfall=8.66" Runoff Area=17,461 sf Runoff Volume=12,252 cf Runoff Depth=8.42" Flow Length=140' Tc=7.4 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 74 76 78 80 Time (hours)

POA-2 2024-05-12 HydroCad - Proposed POA 2B-1 NOAA 24-hr D 100-Year Rainfall=8.66" Prepared by Anderson Consulting Services HydroCAD® 10.20-5c s/n 06666 © 2023 HydroCAD Software Solutions LLC Hydrograph for Subcatchment 53S: Basin 9 - Imp Time Precip. Excess (hours) (inches) (inches) 0.00 0.00 0.00 0.80 0.08 0.01 1.60 0.16 0.05 2.40 0.25 0.11 3.20 0.35 0.19 4.00 0.45 0.28 4.80 0.56 0.38 5.60 0.68 0.48 6.40 0.80 0.60 7.20 0.95 0.74 8.00 1.12 0.91 8.80 1.32 1.10 9.60 1.56 1.34 10.40 1.89 1.67 11.20 2.42 2.19 12.00 4.15 3.91 12.80 6.24 6.00 13.60 6.77 6.53 14.40 7.10 6.86 15.20 7.34 7.10 16.00 7.54 7.30 16.80 7.71 7.47 17.60 7.86 7.62 18.40 7.98 7.74 19.20 8.10 7.86 20.00 8.21 7.97 20.80 8.31 8.07 21.60 8.41 8.17 22.40 8.50 8.26 23.20 8.58 8.34 24.00 8.66 8.42 24.80 8.66 8.42 25.60 8.66 8.42 26.40 8.66 8.42 27.20 8.66 8.42 28.00 8.66 8.42 28.80 8.66 8.42 29.60 8.66 8.42 30.40 8.66 8.42 31.20 8.66 8.42 32.00 8.66 8.42 32.80 8.66 8.42 33.60 8.66 8.42 34.40 8.66 8.42 35.20 8.66 8.42 36.00 8.66 8.42 36.80 8.66 8.42 37.60 8.66 8.42 38.40 8.66 8.42 39.20 8.66 8.42 40.00 8.66 8.42 Runoff (cfs) 0.00 0.01 0.03 0.04 0.04 0.05 0.05 0.06 0.06 0.08 0.09 0.10 0.14 0.18 0.34 1.66 0.42 0.20 0.15 0.11 0.09 0.08 0.07 0.06 0.06 0.05 0.05 0.05 0.04 0.04 0.04 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Time Precip. Excess (hours) (inches)

15 0.11 0.09 0.08 0.07 0.06 0.06 0.05 0.05 0.05 0.04 0.04 0.04 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Time Precip. Excess (hours) (inches) (inches) 40.80 8.66 8.42 41.60 8.66 8.42 42.40 8.66 8.42 43.20 8.66 8.42 44.00 8.66 8.42 44.80 8.66 8.42 45.60 8.66 8.42 46.40 8.66 8.42 47.20 8.66 8.42 48.00 8.66 8.42 48.80 8.66 8.42 49.60 8.66 8.42 50.40 8.66 8.42 51.20 8.66 8.42 52.00 8.66 8.42 52.80 8.66 8.42 53.60 8.66 8.42 54.40 8.66 8.42 55.20 8.66 8.42 56.00 8.66 8.42 56.80 8.66 8.42 57.60 8.66 8.42 58.40 8.66 8.42 59.20 8.66 8.42 60.00 8.66 8.42 60.80 8.66 8.42 61.60 8.66 8.42 62.40 8.66 8.42 63.20 8.66 8.42 64.00 8.66 8.42 64.80 8.66 8.42 65.60 8.66 8.42 66.40 8.66 8.42 67.20 8.66 8.42 68.00 8.66 8.42 68.80 8.66 8.42 69.60 8.66 8.42 70.40 8.66 8.42 71.20 8.66 8.42 72.00 8.66 8.42 72.80 8.66 8.42 73.60 8.66 8.42 74.40 8.66 8.42 75.20 8.66 8.42 76.00 8.66 8.42 76.80 8.66 8.42 77.60 8.66 8.42 78.40 8.66 8.42 79.20 8.66 8.42 80.00 8.66 8.42 Runoff (cfs) 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Printed 10/25/2024 Page 263

POA-2 2024-05-12 HydroCad - Proposed POA 2B-1 NOAA 24-hr D 100-Year Rainfall=8.66" Prepared by Anderson Consulting Services HydroCAD® 10.20-5c s/n 06666 © 2023 HydroCAD Software Solutions LLC Printed 10/25/2024 Page 264 Summary for Subcatchment 54S: Basin 9 - Perv Runoff = 1.31 cfs @ 12.14 hrs, Volume= Routed to Pond 42P : Basin 9 4,461 cf, Depth= 6.00" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-80.00 hrs, dt= 0.04 hrs NOAA 24-hr D 100-Year Rainfall=8.66" Area (sf) 2,537 6,379 8,916 8,916 CN 74 80 78 Description >75% Grass cover, Good, HSG C >75% Grass cover, Good, HSG D Weighted Average 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 7.2 100 0.1000 0.23 Sheet Flow, Sheet Flow (A-B) Grass: Dense n= 0.240 P2= 3.47" 0.2 40 0.0750 4.41 Shallow Concentrated Flow, SCF (B-C) Unpaved Kv= 16.1 fps 7.4 140 Total Sheet Flow (A-B) Subcatchment 54S: Basin 9 - Perv SCF (B-C)

POA-2 2024-05-12 HydroCad - Proposed POA 2B-1 NOAA 24-hr D 100-Year Rainfall=8.66" Prepared by Anderson Consulting Services HydroCAD® 10.20-5c s/n 06666 © 2023 HydroCAD Software Solutions LLC Printed 10/25/2024 Page 265 Subcatchment 54S: Basin 9 - Perv Hydrograph Runoff 1.31 cfs Flow (cfs) 1 NOAA 24-hr D 100-Year Rainfall=8.66" Runoff Area=8,916 sf Runoff Volume=4,461 cf Runoff Depth=6.00" Flow Length=140' Tc=7.4 min CN=78 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 74 76 78 80 Time (hours)

POA-2 2024-05-12 HydroCad - Proposed POA 2B-1 NOAA 24-hr D 100-Year Rainfall=8.66" Prepared by Anderson Consulting Services HydroCAD® 10.20-5c s/n 06666 © 2023 HydroCAD Software Solutions LLC Hydrograph for Subcatchment 54S: Basin 9 - Perv Time Precip. Excess (hours) (inches) (inches) 0.00 0.00 0.00 0.80 0.08 0.00 1.60 0.16 0.00 2.40 0.25 0.00 3.20 0.35 0.00 4.00 0.45 0.00 4.80 0.56 0.00 5.60 0.68 0.00 6.40 0.80 0.02 7.20 0.95 0.05 8.00 1.12 0.09 8.80 1.32 0.16 9.60 1.56 0.26 10.40 1.89 0.43 11.20 2.42 0.74 12.00 4.15 2.01 12.80 6.24 3.79 13.60 6.77 4.26 14.40 7.10 4.56 15.20 7.34 4.78 16.00 7.54 4.96 16.80 7.71 5.12 17.60 7.86 5.26 18.40 7.98 5.37 19.20 8.10 5.48 20.00 8.21 5.58 20.80 8.31 5.68 21.60 8.41 5.77 22.40 8.50 5.85 23.20 8.58 5.93 24.00 8.66 6.00 24.80 8.66 6.00 25.60 8.66 6.00 26.40 8.66 6.00 27.20 8.66 6.00 28.00 8.66 6.00 28.80 8.66 6.00 29.60 8.66 6.00 30.40 8.66 6.00 31.20 8.66 6.00 32.00 8.66 6.00 32.80 8.66 6.00 33.60 8.66 6.00 34.40 8.66 6.00 35.20 8.66 6.00 36.00 8.66 6.00 36.80 8.66 6.00 37.60 8.66 6.00 38.40 8.66 6.00 39.20 8.66 6.00 40.00 8.66 6.00 Runoff (cfs) 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.01 0.01 0.02 0.03 0.05 0.11 0.65 0.19 0.09 0.07 0.05 0.04 0.04 0.03 0.03 0.03 0.03 0.02 0.02 0.02 0.02 0.02 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Time Precip. Excess (hours) (inches)

07 0.05 0.04 0.04 0.03 0.03 0.03 0.03 0.02 0.02 0.02 0.02 0.02 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Time Precip. Excess (hours) (inches) (inches) 40.80 8.66 6.00 41.60 8.66 6.00 42.40 8.66 6.00 43.20 8.66 6.00 44.00 8.66 6.00 44.80 8.66 6.00 45.60 8.66 6.00 46.40 8.66 6.00 47.20 8.66 6.00 48.00 8.66 6.00 48.80 8.66 6.00 49.60 8.66 6.00 50.40 8.66 6.00 51.20 8.66 6.00 52.00 8.66 6.00 52.80 8.66 6.00 53.60 8.66 6.00 54.40 8.66 6.00 55.20 8.66 6.00 56.00 8.66 6.00 56.80 8.66 6.00 57.60 8.66 6.00 58.40 8.66 6.00 59.20 8.66 6.00 60.00 8.66 6.00 60.80 8.66 6.00 61.60 8.66 6.00 62.40 8.66 6.00 63.20 8.66 6.00 64.00 8.66 6.00 64.80 8.66 6.00 65.60 8.66 6.00 66.40 8.66 6.00 67.20 8.66 6.00 68.00 8.66 6.00 68.80 8.66 6.00 69.60 8.66 6.00 70.40 8.66 6.00 71.20 8.66 6.00 72.00 8.66 6.00 72.80 8.66 6.00 73.60 8.66 6.00 74.40 8.66 6.00 75.20 8.66 6.00 76.00 8.66 6.00 76.80 8.66 6.00 77.60 8.66 6.00 78.40 8.66 6.00 79.20 8.66 6.00 80.00 8.66 6.00 Runoff (cfs) 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Printed 10/25/2024 Page 266

POA-2 2024-05-12 HydroCad - Proposed POA 2B-1 NOAA 24-hr D 100-Year Rainfall=8.66" Prepared by Anderson Consulting Services HydroCAD® 10.20-5c s/n 06666 © 2023 HydroCAD Software Solutions LLC Printed 10/25/2024 Page 267 Summary for Pond 21P: Basin 3 Inflow Area = 21,910 sf, 31.15% Impervious, Inflow Depth = 6.42" for 100-Year event Inflow = 3.21 cfs @ 12.15 hrs, Volume= 11,728 cf Outflow = 2.36 cfs @ 12.23 hrs, Volume= 11,728 cf, Atten= 26%, Lag= 4.6 min Discarded = 1.21 cfs @ 12.00 hrs, Volume= 10,971 cf Primary = 1.15 cfs @ 12.23 hrs, Volume= 756 cf Routed to Pond 27P : Basin 2 Routing by Stor-Ind method, Time Span= 0.00-80.00 hrs, dt= 0.04 hrs Peak Elev= 559.42' @ 12.23 hrs Surf.Area= 5,227 sf Storage= 876 cf Plug-Flow detention time= 2.2 min calculated for 11,722 cf (100% of inflow) Center-of-Mass det. time= 2.2 min ( 792.7 - 790.5 ) Volume #1 Invert 559.00' Elevation (feet) 559.00 560.00 561.00 561.17 Device #1 #2 Avail.Storage 4,537 cf Surf.Area (sq-ft) 5,227 5,227 5,227 5,227 Routing Primary Discarded Invert 559.22' 559.00' Storage Description Custom Stage Data (Prismatic) Listed below 11,343 cf Overall x 40.0% Voids Inc.Store (cubic-feet) 0 5,227 5,227 889 Cum.Store (cubic-feet) 0 5,227 10,454 11,343 Outlet Devices 4.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) 10.000 in/hr Exfiltration over Surface area Discarded OutFlow Max=1.21 cfs @ 12.00 hrs HW=559.03' (Free Discharge) 2=Exfiltration (Exfiltration Controls 1.21 cfs) Primary OutFlow Max=1.13 cfs @ 12.23 hrs HW=559.42' (Free Discharge) 1=Sharp-Crested Rectangular Weir (Weir Controls 1.13 cfs @ 1.45 fps) Pond 21P: Basin 3 Sharp-Crested Rectangular Weir Exfiltration

POA-2 NOAA 24-hr D 100-Year Rainfall=8.66" 2024-05-12 HydroCad - Proposed POA 2B-1 Printed 10/25/2024 Page 268 Prepared by Anderson Consulting Services HydroCAD® 10.20-5c s/n 06666 © 2023 HydroCAD Software Solutions LLC Pond 21P: Basin 3 Hydrograph 3.21 cfs Inflow Area=21,910 sf Peak Elev=559.42' Storage=876 cf 3 Flow (cfs) 2.36 cfs Inflow Outflow Discarded Primary 2 1.21 cfs 1.15 cfs 1 0 0 5 10 15 20 25 30 35 40 45 Time (hours) 50 55 60 65 70 75 80 Pond 21P: Basin 3 Stage-Discharge Total Discarded Primary Elevation (feet) 561 560 Sharp-Crested Rectangular Weir Exfiltration 559 0 5 10 15 20 Discharge (cfs) 25 30

POA-2 NOAA 24-hr D 100-Year Rainfall=8.66" 2024-05-12 HydroCad - Proposed POA 2B-1 Printed 10/25/2024 Page 269 Prepared by Anderson Consulting Services HydroCAD® 10.20-5c s/n 06666 © 2023 HydroCAD Software Solutions LLC Pond 21P: Basin 3 Stage-Area-Storage 0 500 1,000 1,500 Surface/Horizontal/Wetted Area (sq-ft) 2,000 2,500 3,000 3,500 4,000 4,500 5,000 Elevation (feet) 561 560 Custom Stage Data 559 0 500 1,000 1,500 2,000 2,500 Storage (cubic-feet) 3,000 3,500 4,000 4,500 Surface Storage