complete drainage report rev 9

POA-2 2024-05-12 HydroCad - Proposed POA 2B-1 NOAA 24-hr D 2-Year Rainfall=3.44" Prepared by Anderson Consulting Services HydroCAD® 10.20-5c s/n 06666 © 2023 HydroCAD Software Solutions LLC Printed 10/25/2024 Page 54 Subcatchment 53S: Basin 9 - Imp Hydrograph Runoff 1.23 cfs Flow (cfs) 1 NOAA 24-hr D 2-Year Rainfall=3.44" Runoff Area=17,461 sf Runoff Volume=4,666 cf Runoff Depth=3.21" 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 2-Year Rainfall=3.44" 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 0.03 0.00 1.60 0.06 0.00 2.40 0.10 0.01 3.20 0.14 0.03 4.00 0.18 0.06 4.80 0.22 0.09 5.60 0.27 0.12 6.40 0.32 0.16 7.20 0.38 0.21 8.00 0.45 0.27 8.80 0.52 0.34 9.60 0.62 0.43 10.40 0.75 0.55 11.20 0.96 0.75 12.00 1.65 1.43 12.80 2.48 2.25 13.60 2.69 2.46 14.40 2.82 2.59 15.20 2.92 2.68 16.00 2.99 2.76 16.80 3.06 2.83 17.60 3.12 2.89 18.40 3.17 2.94 19.20 3.22 2.98 20.00 3.26 3.03 20.80 3.30 3.07 21.60 3.34 3.11 22.40 3.38 3.14 23.20 3.41 3.18 24.00 3.44 3.21 24.80 3.44 3.21 25.60 3.44 3.21 26.40 3.44 3.21 27.20 3.44 3.21 28.00 3.44 3.21 28.80 3.44 3.21 29.60 3.44 3.21 30.40 3.44 3.21 31.20 3.44 3.21 32.00 3.44 3.21 32.80 3.44 3.21 33.60 3.44 3.21 34.40 3.44 3.21 35.20 3.44 3.21 36.00 3.44 3.21 36.80 3.44 3.21 37.60 3.44 3.21 38.40 3.44 3.21 39.20 3.44 3.21 40.00 3.44 3.21 Runoff (cfs) 0.00 0.00 0.00 0.01 0.01 0.01 0.02 0.02 0.02 0.03 0.03 0.04 0.05 0.07 0.13 0.65 0.17 0.08 0.06 0.04 0.04 0.03 0.03 0.02 0.02 0.02 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)

06 0.04 0.04 0.03 0.03 0.02 0.02 0.02 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 3.44 3.21 41.60 3.44 3.21 42.40 3.44 3.21 43.20 3.44 3.21 44.00 3.44 3.21 44.80 3.44 3.21 45.60 3.44 3.21 46.40 3.44 3.21 47.20 3.44 3.21 48.00 3.44 3.21 48.80 3.44 3.21 49.60 3.44 3.21 50.40 3.44 3.21 51.20 3.44 3.21 52.00 3.44 3.21 52.80 3.44 3.21 53.60 3.44 3.21 54.40 3.44 3.21 55.20 3.44 3.21 56.00 3.44 3.21 56.80 3.44 3.21 57.60 3.44 3.21 58.40 3.44 3.21 59.20 3.44 3.21 60.00 3.44 3.21 60.80 3.44 3.21 61.60 3.44 3.21 62.40 3.44 3.21 63.20 3.44 3.21 64.00 3.44 3.21 64.80 3.44 3.21 65.60 3.44 3.21 66.40 3.44 3.21 67.20 3.44 3.21 68.00 3.44 3.21 68.80 3.44 3.21 69.60 3.44 3.21 70.40 3.44 3.21 71.20 3.44 3.21 72.00 3.44 3.21 72.80 3.44 3.21 73.60 3.44 3.21 74.40 3.44 3.21 75.20 3.44 3.21 76.00 3.44 3.21 76.80 3.44 3.21 77.60 3.44 3.21 78.40 3.44 3.21 79.20 3.44 3.21 80.00 3.44 3.21 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 55

POA-2 2024-05-12 HydroCad - Proposed POA 2B-1 NOAA 24-hr D 2-Year Rainfall=3.44" Prepared by Anderson Consulting Services HydroCAD® 10.20-5c s/n 06666 © 2023 HydroCAD Software Solutions LLC Printed 10/25/2024 Page 56 Summary for Subcatchment 54S: Basin 9 - Perv Runoff = 0.33 cfs @ 12.15 hrs, Volume= Routed to Pond 42P : Basin 9 1,079 cf, Depth= 1.45" 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 2-Year Rainfall=3.44" 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 2-Year Rainfall=3.44" Prepared by Anderson Consulting Services HydroCAD® 10.20-5c s/n 06666 © 2023 HydroCAD Software Solutions LLC Printed 10/25/2024 Page 57 Subcatchment 54S: Basin 9 - Perv Hydrograph 0.36 0.34 0.32 0.3 0.28 0.26 0.24 Flow (cfs) 0.22 0.2 0.18 0.16 0.14 0.12 0.1 Runoff 0.33 cfs NOAA 24-hr D 2-Year Rainfall=3.44" Runoff Area=8,916 sf Runoff Volume=1,079 cf Runoff Depth=1.45" Flow Length=140' Tc=7.4 min CN=78 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 74 76 78 80 Time (hours)

POA-2 2024-05-12 HydroCad - Proposed POA 2B-1 NOAA 24-hr D 2-Year Rainfall=3.44" 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 0.03 0.00 1.60 0.06 0.00 2.40 0.10 0.00 3.20 0.14 0.00 4.00 0.18 0.00 4.80 0.22 0.00 5.60 0.27 0.00 6.40 0.32 0.00 7.20 0.38 0.00 8.00 0.45 0.00 8.80 0.52 0.00 9.60 0.62 0.00 10.40 0.75 0.01 11.20 0.96 0.05 12.00 1.65 0.30 12.80 2.48 0.77 13.60 2.69 0.91 14.40 2.82 1.00 15.20 2.92 1.07 16.00 2.99 1.12 16.80 3.06 1.17 17.60 3.12 1.22 18.40 3.17 1.25 19.20 3.22 1.29 20.00 3.26 1.32 20.80 3.30 1.35 21.60 3.34 1.38 22.40 3.38 1.40 23.20 3.41 1.43 24.00 3.44 1.45 24.80 3.44 1.45 25.60 3.44 1.45 26.40 3.44 1.45 27.20 3.44 1.45 28.00 3.44 1.45 28.80 3.44 1.45 29.60 3.44 1.45 30.40 3.44 1.45 31.20 3.44 1.45 32.00 3.44 1.45 32.80 3.44 1.45 33.60 3.44 1.45 34.40 3.44 1.45 35.20 3.44 1.45 36.00 3.44 1.45 36.80 3.44 1.45 37.60 3.44 1.45 38.40 3.44 1.45 39.20 3.44 1.45 40.00 3.44 1.45 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 0.01 0.14 0.05 0.03 0.02 0.02 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 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)

02 0.02 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 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 3.44 1.45 41.60 3.44 1.45 42.40 3.44 1.45 43.20 3.44 1.45 44.00 3.44 1.45 44.80 3.44 1.45 45.60 3.44 1.45 46.40 3.44 1.45 47.20 3.44 1.45 48.00 3.44 1.45 48.80 3.44 1.45 49.60 3.44 1.45 50.40 3.44 1.45 51.20 3.44 1.45 52.00 3.44 1.45 52.80 3.44 1.45 53.60 3.44 1.45 54.40 3.44 1.45 55.20 3.44 1.45 56.00 3.44 1.45 56.80 3.44 1.45 57.60 3.44 1.45 58.40 3.44 1.45 59.20 3.44 1.45 60.00 3.44 1.45 60.80 3.44 1.45 61.60 3.44 1.45 62.40 3.44 1.45 63.20 3.44 1.45 64.00 3.44 1.45 64.80 3.44 1.45 65.60 3.44 1.45 66.40 3.44 1.45 67.20 3.44 1.45 68.00 3.44 1.45 68.80 3.44 1.45 69.60 3.44 1.45 70.40 3.44 1.45 71.20 3.44 1.45 72.00 3.44 1.45 72.80 3.44 1.45 73.60 3.44 1.45 74.40 3.44 1.45 75.20 3.44 1.45 76.00 3.44 1.45 76.80 3.44 1.45 77.60 3.44 1.45 78.40 3.44 1.45 79.20 3.44 1.45 80.00 3.44 1.45 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 58

POA-2 2024-05-12 HydroCad - Proposed POA 2B-1 NOAA 24-hr D 2-Year Rainfall=3.44" Prepared by Anderson Consulting Services HydroCAD® 10.20-5c s/n 06666 © 2023 HydroCAD Software Solutions LLC Printed 10/25/2024 Page 59 Summary for Pond 21P: Basin 3 Inflow Area = 21,910 sf, 31.15% Impervious, Inflow Depth = 1.82" for 2-Year event Inflow = 0.90 cfs @ 12.16 hrs, Volume= 3,330 cf Outflow = 0.89 cfs @ 12.17 hrs, Volume= 3,330 cf, Atten= 1%, Lag= 0.6 min Discarded = 0.89 cfs @ 12.17 hrs, Volume= 3,330 cf Primary = 0.00 cfs @ 0.00 hrs, Volume= 0 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= 559.02' @ 12.17 hrs Surf.Area= 5,227 sf Storage= 33 cf Plug-Flow detention time= 0.6 min calculated for 3,329 cf (100% of inflow) Center-of-Mass det. time= 0.6 min ( 810.9 - 810.2 ) 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 @ 12.17 hrs HW=559.02' (Free Discharge) 2=Exfiltration (Exfiltration Controls 1.21 cfs) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=559.00' (Free Discharge) 1=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs) Pond 21P: Basin 3 Sharp-Crested Rectangular Weir Exfiltration

POA-2 NOAA 24-hr D 2-Year Rainfall=3.44" 2024-05-12 HydroCad - Proposed POA 2B-1 Printed 10/25/2024 Page 60 Prepared by Anderson Consulting Services HydroCAD® 10.20-5c s/n 06666 © 2023 HydroCAD Software Solutions LLC Pond 21P: Basin 3 Hydrograph 0.90 cfs Inflow Area=21,910 sf Peak Elev=559.02' Storage=33 cf 0.89 cfs 1 Flow (cfs) 0.89 cfs Inflow Outflow Discarded Primary 0.00 cfs 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 2-Year Rainfall=3.44" 2024-05-12 HydroCad - Proposed POA 2B-1 Printed 10/25/2024 Page 61 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