Drainage Report

Basin 2-5 without exfiltration Proposed Basin 2-5 R5 NOAA 24-hr D 100-Year Rainfall=8.66" Prepared by Anderson Consulting Services Printed 10/29/2023 HydroCAD® 10.20-3f s/n 06666 © 2023 HydroCAD Software Solutions LLC Page 29 Summary for Subcatchment 38S: Basin 2-5 [47] Hint: Peak is 987% of capacity of segment #2 Runoff = 11.68 cfs @ 12.17 hrs, Volume= 1.158 af, Depth= 8.42" Routed to Pond 39P : pond 2-5 Runoff by SCS TR-20 method, UH=SCS, Split Pervious/Imperv., Time Span= 0.00-72.00 hrs, dt= 0.05 hrs NOAA 24-hr D 100-Year Rainfall=8.66" Area (sf) CN Description 60,317 98 Roofs, HSG C 11,558 98 Water Surface, 0% imp, HSG C 71,875 98 Weighted Average Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 1.5 100 0.0100 1.08 Sheet Flow, Smooth surfaces n= 0.011 P2= 3.44" 3.0 920 0.0410 5.17 1.18 Pipe Channel, 12.0" Round w/ 8.0" inside fill Area= 0.2 sf Perim= 2.2' r= 0.11' n= 0.013 4.5 1,020 Total, Increased to minimum Tc = 10.0 min Subcatchment 38S: Basin 2-5 Hydrograph 13 Runoff 11.68 cfs 12 11 NOAA 24-hr D 10

cfs 12 11 NOAA 24-hr D 10 100-Year Rainfall=8.66" 9 Runoff Area=71,875 sf 8 Runoff Volume=1.158 af Flow (cfs) 7 Runoff Depth=8.42" 6 Flow Length=1,020' 5 Tc=10.0 min 4 CN=98/98 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)

Basin 2-5 without exfiltration Proposed Basin 2-5 R5 NOAA 24-hr D 100-Year Rainfall=8.66" Prepared by Anderson Consulting Services Printed 10/29/2023 HydroCAD® 10.20-3f s/n 06666 © 2023 HydroCAD Software Solutions LLC Page 30 Hydrograph for Subcatchment 38S: Basin 2-5 Time Precip. Perv.Excess Imp.Excess Runoff (hours) (inches) (inches) (inches) (cfs) 0.00 0.00 0.00 0.00 0.00 2.50 0.27 0.12 0.12 0.15 5.00 0.59 0.40 0.40 0.22 7.50 1.01 0.80 0.80 0.33 10.00 1.72 1.49 1.49 0.64 12.50 5.91 5.68 5.68 3.10 15.00 7.29 7.05 7.05 0.49 17.50 7.84 7.60 7.60 0.30 20.00 8.21 7.97 7.97 0.22 22.50 8.51 8.27 8.27 0.18 25.00 8.66 8.42 8.42 0.00 27.50 8.66 8.42 8.42 0.00 30.00 8.66 8.42 8.42 0.00 32.50 8.66 8.42 8.42 0.00 35.00 8.66 8.42 8.42 0.00 37.50 8.66 8.42 8.42 0.00 40.00 8.66 8.42 8.42 0.00 42.50 8.66 8.42 8.42 0.00 45.00 8.66 8.42 8.42 0.00 47.50 8.66 8.42 8.42 0.00 50.00 8.66 8.42 8.42 0.00 52.50 8.66 8.42 8.42 0.00 55.00 8.66 8.42 8.42 0.00 57.50 8.66 8.42 8.42 0.00 60.00 8.66 8.42 8.42 0.00 62.50 8.66 8.42 8.42 0.00 65.00 8.66 8.42 8.42 0.00 67.50 8.66 8.42 8.42 0.00 70.00 8.66 8.42 8.42 0.00

Basin 2-5 without exfiltration Proposed Basin 2-5 R5 NOAA 24-hr D 100-Year Rainfall=8.66" Prepared by Anderson Consulting Services Printed 10/29/2023 HydroCAD® 10.20-3f s/n 06666 © 2023 HydroCAD Software Solutions LLC Page 31 Summary for Subcatchment 42S: Basin 2-5 predevelopment Runoff = 7.48 cfs @ 12.21 hrs, Volume= 0.693 af, Depth= 5.04" Runoff by SCS TR-20 method, UH=SCS, Split Pervious/Imperv., Time Span= 0.00-72.00 hrs, dt= 0.05 hrs NOAA 24-hr D 100-Year Rainfall=8.66" Area (sf) CN Description 71,875 70 Woods, Good, HSG C Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 11.9 100 0.0800 0.14 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 3.44" 1.3 120 0.1000 1.58 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 13.2 220 Total Subcatchment 42S: Basin 2-5 predevelopment Hydrograph Runoff 8 7.48 cfs 7 NOAA 24-hr D 100-Year Rainfall=8.66" 6 Runoff Area=71,875 sf 5 Runoff Volume=0.693 af Flow (cfs) Runoff Depth=5.04"

Runoff Volume=0.693 af Flow (cfs) Runoff Depth=5.04" 4 Flow Length=220' 3 Tc=13.2 min CN=70/0 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)

Basin 2-5 without exfiltration Proposed Basin 2-5 R5 NOAA 24-hr D 100-Year Rainfall=8.66" Prepared by Anderson Consulting Services Printed 10/29/2023 HydroCAD® 10.20-3f s/n 06666 © 2023 HydroCAD Software Solutions LLC Page 32 Hydrograph for Subcatchment 42S: Basin 2-5 predevelopment Time Precip. Perv.Excess Imp.Excess Runoff (hours) (inches) (inches) (inches) (cfs) 0.00 0.00 0.00 0.00 0.00 2.50 0.27 0.00 0.00 0.00 5.00 0.59 0.00 0.00 0.00 7.50 1.01 0.01 0.00 0.02 10.00 1.72 0.14 0.00 0.18 12.50 5.91 2.74 0.00 2.84 15.00 7.29 3.86 0.00 0.42 17.50 7.84 4.33 0.00 0.26 20.00 8.21 4.64 0.00 0.19 22.50 8.51 4.90 0.00 0.16 25.00 8.66 5.04 0.00 0.00 27.50 8.66 5.04 0.00 0.00 30.00 8.66 5.04 0.00 0.00 32.50 8.66 5.04 0.00 0.00 35.00 8.66 5.04 0.00 0.00 37.50 8.66 5.04 0.00 0.00 40.00 8.66 5.04 0.00 0.00 42.50 8.66 5.04 0.00 0.00 45.00 8.66 5.04 0.00 0.00 47.50 8.66 5.04 0.00 0.00 50.00 8.66 5.04 0.00 0.00 52.50 8.66 5.04 0.00 0.00 55.00 8.66 5.04 0.00 0.00 57.50 8.66 5.04 0.00 0.00 60.00 8.66 5.04 0.00 0.00 62.50 8.66 5.04 0.00 0.00 65.00 8.66 5.04 0.00 0.00 67.50 8.66 5.04 0.00 0.00 70.00 8.66 5.04 0.00 0.00

Basin 2-5 without exfiltration Proposed Basin 2-5 R5 NOAA 24-hr D 100-Year Rainfall=8.66" Prepared by Anderson Consulting Services Printed 10/29/2023 HydroCAD® 10.20-3f s/n 06666 © 2023 HydroCAD Software Solutions LLC Page 33 Summary for Pond 39P: pond 2-5 Inflow Area = 1.650 ac, Inflow Depth = 8.42" for 100-Year event Inflow = 11.68 cfs @ 12.17 hrs, Volume= 1.158 af Outflow = 1.16 cfs @ 13.26 hrs, Volume= 0.888 af, Atten= 90%, Lag= 65.6 min Primary = 1.16 cfs @ 13.26 hrs, Volume= 0.888 af Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Peak Elev= 543.27' @ 13.26 hrs Surf.Area= 11,558 sf Storage= 31,977 cf Plug-Flow detention time= 438.9 min calculated for 0.888 af (77% of inflow) Center-of-Mass det. time= 346.1 min ( 1,090.8 - 744.7 ) Volume Invert Avail.Storage Storage Description #1 540.50' 40,453 cf 540 (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 540.50 11,558 0 0 544.00 11,558 40,453 40,453 Device Routing Invert Outlet Devices #1 Primary 541.50' 6.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=1.16 cfs @ 13.26 hrs HW=543.27' (Free Discharge) 1=Orifice/Grate (Orifice Controls 1.16 cfs @ 5.93 fps)

Basin 2-5 without exfiltration Proposed Basin 2-5 R5 NOAA 24-hr D 100-Year Rainfall=8.66" Prepared by Anderson Consulting Services Printed 10/29/2023 HydroCAD® 10.20-3f s/n 06666 © 2023 HydroCAD Software Solutions LLC Page 34 Pond 39P: pond 2-5 Hydrograph Inflow 13 11.68 cfs Primary 12 Inflow Area=1.650 ac Peak Elev=543.27' 11 10 9 Storage=31,977 cf 8 Flow (cfs) 7 6 5 4 3 2 1.16 cfs 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)

Basin 2-5 without exfiltration Proposed Basin 2-5 R5 NOAA 24-hr D 100-Year Rainfall=8.66" Prepared by Anderson Consulting Services Printed 10/29/2023 HydroCAD® 10.20-3f s/n 06666 © 2023 HydroCAD Software Solutions LLC Page 35 Hydrograph for Pond 39P: pond 2-5 Time Inflow Storage Elevation Primary (hours) (cfs) (cubic-feet) (feet) (cfs) 0.00 0.00 0 540.50 0.00 2.50 0.15 624 540.55 0.00 5.00 0.22 2,288 540.70 0.00 7.50 0.33 4,628 540.90 0.00 10.00 0.64 8,585 541.24 0.00 12.50 3.10 30,146 543.11 1.10 15.00 0.49 29,442 543.05 1.08 17.50 0.30 24,098 542.58 0.86 20.00 0.22 19,608 542.20 0.63 22.50 0.18 16,724 541.95 0.42 25.00 0.00 14,856 541.79 0.21 27.50 0.00 13,607 541.68 0.09 30.00 0.00 13,017 541.63 0.05 32.50 0.00 12,682 541.60 0.03 35.00 0.00 12,469 541.58 0.02 37.50 0.00 12,319 541.57 0.01 40.00 0.00 12,209 541.56 0.01 42.50 0.00 12,129 541.55 0.01 45.00 0.00 12,066 541.54 0.01 47.50 0.00 12,011 541.54 0.01 50.00 0.00 11,964 541.54 0.00 52.50 0.00 11,925 541.53 0.00 55.00 0.00 11,890 541.53 0.00 57.50 0.00 11,861 541.53 0.00 60.00 0.00 11,836 541.52 0.00 62.50 0.00 11,815 541.52 0.00 65.00 0.00 11,797 541.52 0.00 67.50 0.00 11,782 541.52 0.00 70.00 0.00 11,768 541.52 0.00

Basin 2-5 without exfiltration Proposed Basin 2-5 R5 NOAA 24-hr D 100-Year Rainfall=8.66" Prepared by Anderson Consulting Services Printed 10/29/2023 HydroCAD® 10.20-3f s/n 06666 © 2023 HydroCAD Software Solutions LLC Page 36 Stage-Discharge for Pond 39P: pond 2-5 Elevation Primary Elevation Primary Elevation Primary Elevation Primary (feet) (cfs) (feet) (cfs) (feet) (cfs) (feet) (cfs) 540.50 0.00 541.52 0.00 542.54 0.84 543.56 1.27 540.52 0.00 541.54 0.01 542.56 0.85 543.58 1.28 540.54 0.00 541.56 0.01 542.58 0.86 543.60 1.29 540.56 0.00 541.58 0.02 542.60 0.87 543.62 1.29 540.58 0.00 541.60 0.03 542.62 0.88 543.64 1.30 540.60 0.00 541.62 0.04 542.64 0.89 543.66 1.31 540.62 0.00 541.64 0.06 542.66 0.90 543.68 1.31 540.64 0.00 541.66 0.07 542.68 0.91 543.70 1.32 540.66 0.00 541.68 0.09 542.70 0.92 543.72 1.33 540.68 0.00 541.70 0.11 542.72 0.93 543.74 1.33 540.70 0.00 541.72 0.13 542.74 0.94 543.76 1.34 540.72 0.00 541.74 0.16 542.76 0.95 543.78 1.35 540.74 0.00 541.76 0.18 542.78 0.96 543.80 1.35 540.76 0.00 541.78 0.20 542.80 0.97 543.82 1.36 540.78 0.00 541.80 0.23 542.82 0.98 543.84 1.37 540.80 0.00 541.82 0.26 542.84 0.99 543.86 1.37 540.82 0.00 541.84 0.28 542.86 1.00 543.88 1.38 540.84 0.00 541.86 0.31 542.88 1.00 543.90 1.39 540.86 0.00 541.88 0.34 542.90 1.01