Drainage Report

Basin 2-5 without exfiltration Proposed Basin 2-5 R5 NOAA 24-hr D 2-Year Rainfall=3.44" Prepared by Anderson Consulting Services Printed 10/29/2023 HydroCAD® 10.20-3f s/n 06666 © 2023 HydroCAD Software Solutions LLC Page 9 Summary for Subcatchment 38S: Basin 2-5 [47] Hint: Peak is 388% of capacity of segment #2 Runoff = 4.60 cfs @ 12.17 hrs, Volume= 0.441 af, Depth= 3.21" 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 2-Year Rainfall=3.44" 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 5 Runoff 4.60 cfs NOAA 24-hr D 4 2-Year Rainfall=3.44"

NOAA 24-hr D 4 2-Year Rainfall=3.44" Runoff Area=71,875 sf 3 Runoff Volume=0.441 af Flow (cfs) Runoff Depth=3.21" Flow Length=1,020' 2 Tc=10.0 min CN=98/98 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 2-Year Rainfall=3.44" Prepared by Anderson Consulting Services Printed 10/29/2023 HydroCAD® 10.20-3f s/n 06666 © 2023 HydroCAD Software Solutions LLC Page 10 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 0.11 0.02 0.02 0.03 5.00 0.24 0.09 0.09 0.07 7.50 0.40 0.23 0.23 0.12 10.00 0.68 0.49 0.49 0.24 12.50 2.35 2.12 2.12 1.22 15.00 2.89 2.66 2.66 0.19 17.50 3.11 2.88 2.88 0.12 20.00 3.26 3.03 3.03 0.09 22.50 3.38 3.15 3.15 0.07 25.00 3.44 3.21 3.21 0.00 27.50 3.44 3.21 3.21 0.00 30.00 3.44 3.21 3.21 0.00 32.50 3.44 3.21 3.21 0.00 35.00 3.44 3.21 3.21 0.00 37.50 3.44 3.21 3.21 0.00 40.00 3.44 3.21 3.21 0.00 42.50 3.44 3.21 3.21 0.00 45.00 3.44 3.21 3.21 0.00 47.50 3.44 3.21 3.21 0.00 50.00 3.44 3.21 3.21 0.00 52.50 3.44 3.21 3.21 0.00 55.00 3.44 3.21 3.21 0.00 57.50 3.44 3.21 3.21 0.00 60.00 3.44 3.21 3.21 0.00 62.50 3.44 3.21 3.21 0.00 65.00 3.44 3.21 3.21 0.00 67.50 3.44 3.21 3.21 0.00 70.00 3.44 3.21 3.21 0.00

Basin 2-5 without exfiltration Proposed Basin 2-5 R5 NOAA 24-hr D 2-Year Rainfall=3.44" Prepared by Anderson Consulting Services Printed 10/29/2023 HydroCAD® 10.20-3f s/n 06666 © 2023 HydroCAD Software Solutions LLC Page 11 Summary for Subcatchment 42S: Basin 2-5 predevelopment Runoff = 1.34 cfs @ 12.22 hrs, Volume= 0.134 af, Depth= 0.97" 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 2-Year Rainfall=3.44" 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 1.34 cfs NOAA 24-hr D 2-Year Rainfall=3.44" 1 Runoff Area=71,875 sf Runoff Volume=0.134 af Flow (cfs) Runoff Depth=0.97"

0.134 af Flow (cfs) Runoff Depth=0.97" Flow Length=220' Tc=13.2 min CN=70/0 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 2-Year Rainfall=3.44" Prepared by Anderson Consulting Services Printed 10/29/2023 HydroCAD® 10.20-3f s/n 06666 © 2023 HydroCAD Software Solutions LLC Page 12 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 0.11 0.00 0.00 0.00 5.00 0.24 0.00 0.00 0.00 7.50 0.40 0.00 0.00 0.00 10.00 0.68 0.00 0.00 0.00 12.50 2.35 0.39 0.00 0.60 15.00 2.89 0.66 0.00 0.11 17.50 3.11 0.78 0.00 0.07 20.00 3.26 0.86 0.00 0.05 22.50 3.38 0.93 0.00 0.04 25.00 3.44 0.97 0.00 0.00 27.50 3.44 0.97 0.00 0.00 30.00 3.44 0.97 0.00 0.00 32.50 3.44 0.97 0.00 0.00 35.00 3.44 0.97 0.00 0.00 37.50 3.44 0.97 0.00 0.00 40.00 3.44 0.97 0.00 0.00 42.50 3.44 0.97 0.00 0.00 45.00 3.44 0.97 0.00 0.00 47.50 3.44 0.97 0.00 0.00 50.00 3.44 0.97 0.00 0.00 52.50 3.44 0.97 0.00 0.00 55.00 3.44 0.97 0.00 0.00 57.50 3.44 0.97 0.00 0.00 60.00 3.44 0.97 0.00 0.00 62.50 3.44 0.97 0.00 0.00 65.00 3.44 0.97 0.00 0.00 67.50 3.44 0.97 0.00 0.00 70.00 3.44 0.97 0.00 0.00

Basin 2-5 without exfiltration Proposed Basin 2-5 R5 NOAA 24-hr D 2-Year Rainfall=3.44" Prepared by Anderson Consulting Services Printed 10/29/2023 HydroCAD® 10.20-3f s/n 06666 © 2023 HydroCAD Software Solutions LLC Page 13 Summary for Pond 39P: pond 2-5 Inflow Area = 1.650 ac, Inflow Depth = 3.21" for 2-Year event Inflow = 4.60 cfs @ 12.17 hrs, Volume= 0.441 af Outflow = 0.19 cfs @ 15.07 hrs, Volume= 0.171 af, Atten= 96%, Lag= 174.2 min Primary = 0.19 cfs @ 15.07 hrs, Volume= 0.171 af Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Peak Elev= 541.77' @ 15.07 hrs Surf.Area= 11,558 sf Storage= 14,645 cf Plug-Flow detention time= 707.2 min calculated for 0.171 af (39% of inflow) Center-of-Mass det. time= 539.3 min ( 1,299.8 - 760.4 ) 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=0.19 cfs @ 15.07 hrs HW=541.77' (Free Discharge) 1=Orifice/Grate (Orifice Controls 0.19 cfs @ 1.76 fps)

Basin 2-5 without exfiltration Proposed Basin 2-5 R5 NOAA 24-hr D 2-Year Rainfall=3.44" Prepared by Anderson Consulting Services Printed 10/29/2023 HydroCAD® 10.20-3f s/n 06666 © 2023 HydroCAD Software Solutions LLC Page 14 Pond 39P: pond 2-5 Hydrograph Inflow 5 4.60 cfs Primary Inflow Area=1.650 ac 4 Peak Elev=541.77' Storage=14,645 cf 3 Flow (cfs) 2 1 0.19 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)

Basin 2-5 without exfiltration Proposed Basin 2-5 R5 NOAA 24-hr D 2-Year Rainfall=3.44" Prepared by Anderson Consulting Services Printed 10/29/2023 HydroCAD® 10.20-3f s/n 06666 © 2023 HydroCAD Software Solutions LLC Page 15 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 0.03 76 540.51 0.00 5.00 0.07 530 540.55 0.00 7.50 0.12 1,319 540.61 0.00 10.00 0.24 2,776 540.74 0.00 12.50 1.22 12,084 541.55 0.01 15.00 0.19 14,644 541.77 0.19 17.50 0.12 14,394 541.75 0.16 20.00 0.09 14,003 541.71 0.12 22.50 0.07 13,728 541.69 0.10 25.00 0.00 13,337 541.65 0.07 27.50 0.00 12,871 541.61 0.04 30.00 0.00 12,590 541.59 0.02 32.50 0.00 12,406 541.57 0.02 35.00 0.00 12,273 541.56 0.01 37.50 0.00 12,176 541.55 0.01 40.00 0.00 12,104 541.55 0.01 42.50 0.00 12,044 541.54 0.01 45.00 0.00 11,992 541.54 0.01 47.50 0.00 11,948 541.53 0.00 50.00 0.00 11,911 541.53 0.00 52.50 0.00 11,879 541.53 0.00 55.00 0.00 11,851 541.53 0.00 57.50 0.00 11,828 541.52 0.00 60.00 0.00 11,808 541.52 0.00 62.50 0.00 11,791 541.52 0.00 65.00 0.00 11,776 541.52 0.00 67.50 0.00 11,764 541.52 0.00 70.00 0.00 11,753 541.52 0.00

Basin 2-5 without exfiltration Proposed Basin 2-5 R5 NOAA 24-hr D 2-Year Rainfall=3.44" Prepared by Anderson Consulting Services Printed 10/29/2023 HydroCAD® 10.20-3f s/n 06666 © 2023 HydroCAD Software Solutions LLC Page 16 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