Drainage Report

37,737 541.50 10,782 10,782 541.55 10,782 11,321 541.60 10,782 11,860 541.65 10,782 12,399 541.70 10,782 12,938 541.75 10,782 13,478 541.80 10,782 14,017 541.85 10,782 14,556 541.90 10,782 15,095 541.95 10,782 15,634 542.00 10,782 16,173 542.05 10,782 16,712 542.10 10,782 17,251 542.15 10,782 17,790 542.20 10,782 18,329 542.25 10,782 18,869 542.30 10,782 19,408 542.35 10,782 19,947 542.40 10,782 20,486 542.45 10,782 21,025 542.50 10,782 21,564 542.55 10,782 22,103 542.60 10,782 22,642 542.65 10,782 23,181 542.70 10,782 23,720 542.75 10,782 24,260 542.80 10,782 24,799 542.85 10,782 25,338 542.90 10,782 25,877 542.95 10,782 26,416 543.00 10,782 26,955

Basin 2-6 without exfiltration Proposed basin 2-6 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 28 Time span=0.00-72.00 hrs, dt=0.05 hrs, 1441 points Runoff by SCS TR-20 method, UH=SCS, Split Pervious/Imperv. Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment 36S: Basin 2-6 Runoff Area=80,223 sf Runoff Depth=8.42" Flow Length=1,762' Tc=10.0 min CN=98/98 Runoff=13.04 cfs 1.292 af Subcatchment 42S: basin 2-6 pre-development Runoff Area=80,223 sf Runoff Depth=5.04" Flow Length=230' Tc=17.3 min CN=70/0 Runoff=7.47 cfs 0.773 af Pond 37P: Pond 2-6 Peak Elev=543.84' Storage=36,022 cf Inflow=13.04 cfs 1.292 af Outflow=1.27 cfs 0.966 af Total Runoff Area = 3.683 ac Runoff Volume = 2.065 af Average Runoff Depth = 6.73"

Basin 2-6 without exfiltration Proposed basin 2-6 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 36S: Basin 2-6 [47] Hint: Peak is 747% of capacity of segment #3 Runoff = 13.04 cfs @ 12.17 hrs, Volume= 1.292 af, Depth= 8.42" Routed to Pond 37P : Pond 2-6 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 69,441 98 Roofs, HSG C 10,782 98 Water Surface, 0% imp, HSG C 80,223 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" 0.3 40 0.0100 2.03 Shallow Concentrated Flow, Paved Kv= 20.3 fps 4.8 1,622 0.0370 5.63 1.74 Pipe Channel, 12.0" Round w/ 7.0" inside fill Area= 0.3 sf Perim= 2.4' r= 0.13' n= 0.013 6.7 1,762 Total, Increased to minimum Tc = 10.0 min Subcatchment 36S: Basin 2-6 Hydrograph Runoff 14 13.04 cfs 13

Runoff 14 13.04 cfs 13 NOAA 24-hr D 12 11 100-Year Rainfall=8.66" 10 Runoff Area=80,223 sf 9 Runoff Volume=1.292 af Flow (cfs) 8 Runoff Depth=8.42" 7 6 Flow Length=1,762' 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 2-6 without exfiltration Proposed basin 2-6 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 36S: Basin 2-6 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 0.16 5.00 0.59 0.40 0.40 0.24 7.50 1.01 0.80 0.80 0.37 10.00 1.72 1.49 1.49 0.72 12.50 5.91 5.68 5.68 3.46 15.00 7.29 7.05 7.05 0.55 17.50 7.84 7.60 7.60 0.33 20.00 8.21 7.97 7.97 0.25 22.50 8.51 8.27 8.27 0.20 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 2-6 without exfiltration Proposed basin 2-6 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 2-6 pre-development Runoff = 7.47 cfs @ 12.26 hrs, Volume= 0.773 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 80,223 70 Woods, Good, HSG C Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 15.7 100 0.0400 0.11 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 3.44" 1.6 130 0.0700 1.32 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 17.3 230 Total Subcatchment 42S: basin 2-6 pre-development Hydrograph Runoff 8 7.47 cfs 7 NOAA 24-hr D 100-Year Rainfall=8.66" 6 Runoff Area=80,223 sf 5 Runoff Volume=0.773 af Flow (cfs) Runoff Depth=5.04" 4

Runoff Volume=0.773 af Flow (cfs) Runoff Depth=5.04" 4 Flow Length=230' 3 Tc=17.3 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 2-6 without exfiltration Proposed basin 2-6 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 2-6 pre-development 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 0.19 12.50 5.91 2.74 0.00 3.96 15.00 7.29 3.86 0.00 0.48 17.50 7.84 4.33 0.00 0.29 20.00 8.21 4.64 0.00 0.22 22.50 8.51 4.90 0.00 0.18 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 2-6 without exfiltration Proposed basin 2-6 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 37P: Pond 2-6 Inflow Area = 1.842 ac, Inflow Depth = 8.42" for 100-Year event Inflow = 13.04 cfs @ 12.17 hrs, Volume= 1.292 af Outflow = 1.27 cfs @ 13.29 hrs, Volume= 0.966 af, Atten= 90%, Lag= 67.5 min Primary = 1.27 cfs @ 13.29 hrs, Volume= 0.966 af Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Peak Elev= 543.84' @ 13.29 hrs Surf.Area= 10,782 sf Storage= 36,022 cf Plug-Flow detention time= 438.5 min calculated for 0.966 af (75% of inflow) Center-of-Mass det. time= 341.7 min ( 1,086.4 - 744.7 ) Volume Invert Avail.Storage Storage Description #1 540.50' 37,737 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 540.50 10,782 0 0 544.00 10,782 37,737 37,737 Device Routing Invert Outlet Devices #1 Primary 541.80' 6.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=1.27 cfs @ 13.29 hrs HW=543.84' (Free Discharge) 1=Orifice/Grate (Orifice Controls 1.27 cfs @ 6.44 fps)

Basin 2-6 without exfiltration Proposed basin 2-6 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 37P: Pond 2-6 Hydrograph Inflow 13.04 cfs Primary 14 13 Inflow Area=1.842 ac 12 Peak Elev=543.84' 11 10 Storage=36,022 cf 9 Flow (cfs) 8 7 6 5 4 3 2 1.27 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)