Drainage Report

Basin 5 witout exfiltration Proposed basin 5 R5 Prepared by Anderson Consulting Services Printed 10/29/2023 HydroCAD® 10.20-3f s/n 06666 © 2023 HydroCAD Software Solutions LLC Page 4 Area Listing (all nodes) Area CN Description (acres) (subcatchment-numbers) 1.911 74 >75% Grass cover, Good, HSG C (23S, 25S) 0.510 98 Paved parking, HSG C (25S) 1.430 98 Roofs, HSG D (23S) 3.850 70 Woods, Good, HSG C (26S) 7.701 78 TOTAL AREA

Basin 5 witout exfiltration Proposed basin 5 R5 Prepared by Anderson Consulting Services Printed 10/29/2023 HydroCAD® 10.20-3f s/n 06666 © 2023 HydroCAD Software Solutions LLC Page 5 Soil Listing (all nodes) Area Soil Subcatchment (acres) Group Numbers 0.000 HSG A 0.000 HSG B 6.271 HSG C 23S, 25S, 26S 1.430 HSG D 23S 0.000 Other 7.701 TOTAL AREA

Basin 5 witout exfiltration Proposed basin 5 R5 Prepared by Anderson Consulting Services Printed 10/29/2023 HydroCAD® 10.20-3f s/n 06666 © 2023 HydroCAD Software Solutions LLC Page 6 Ground Covers (all nodes) HSG-A HSG-B HSG-C HSG-D Other Total Ground Subcatchment (acres) (acres) (acres) (acres) (acres) (acres) Cover Numbers 0.000 0.000 1.911 0.000 0.000 1.911 >75% Grass cover, Good 23S, 25S 0.000 0.000 0.510 0.000 0.000 0.510 Paved parking 25S 0.000 0.000 0.000 1.430 0.000 1.430 Roofs 23S 0.000 0.000 3.850 0.000 0.000 3.850 Woods, Good 26S 0.000 0.000 6.271 1.430 0.000 7.701 TOTAL AREA

Basin 5 witout exfiltration Proposed basin 5 R5 Prepared by Anderson Consulting Services Printed 10/29/2023 HydroCAD® 10.20-3f s/n 06666 © 2023 HydroCAD Software Solutions LLC Page 7 Pipe Listing (all nodes) Line# Node In-Invert Out-Invert Length Slope n Width Diam/Height Inside-Fill Node Number (feet) (feet) (feet) (ft/ft) (inches) (inches) (inches) Name 1 25S 0.00 0.00 156.0 0.0349 0.013 0.0 15.0 8.0

Basin 5 witout exfiltration Proposed basin 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 8 Time span=0.00-72.00 hrs, dt=0.03 hrs, 2401 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 23S: Basin 5 Runoff Area=99,084 sf Runoff Depth=2.46" Flow Length=314' Tc=11.3 min CN=74/98 Runoff=4.83 cfs 0.466 af Subcatchment 25S: overland 5-A Runoff Area=68,635 sf Runoff Depth=1.85" Flow Length=394' Tc=7.6 min CN=74/98 Runoff=2.94 cfs 0.243 af Subcatchment 26S: pre-dev basin 5 Runoff Area=167,719 sf Runoff Depth=0.97" Flow Length=274' Tc=11.5 min CN=70/0 Runoff=3.33 cfs 0.312 af Pond 24P: Infiltration basin 5 Peak Elev=572.14' Storage=20,319 cf Inflow=4.83 cfs 0.466 af Outflow=0.00 cfs 0.000 af Total Runoff Area = 7.701 ac Runoff Volume = 1.021 af Average Runoff Depth = 1.59"

Basin 5 witout exfiltration Proposed basin 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 23S: Basin 5 Runoff = 4.83 cfs @ 12.19 hrs, Volume= 0.466 af, Depth= 2.46" Routed to Pond 24P : Infiltration basin 5 Runoff by SCS TR-20 method, UH=SCS, Split Pervious/Imperv., Time Span= 0.00-72.00 hrs, dt= 0.03 hrs NOAA 24-hr D 2-Year Rainfall=3.44" Area (sf) CN Description 62,281 98 Roofs, HSG D 36,803 74 >75% Grass cover, Good, HSG C 99,084 89 Weighted Average Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 10.1 100 0.0170 0.17 Sheet Flow, Grass: Short n= 0.150 P2= 3.44" 1.0 164 0.0305 2.62 Shallow Concentrated Flow, Grassed Waterway Kv= 15.0 fps 0.1 50 0.0760 5.60 Shallow Concentrated Flow, Paved Kv= 20.3 fps 11.3 314 Total Subcatchment 23S: Basin 5 Hydrograph Runoff 5 4.83 cfs NOAA 24-hr D 2-Year Rainfall=3.44" 4

-hr D 2-Year Rainfall=3.44" 4 Runoff Area=99,084 sf Runoff Volume=0.466 af Flow (cfs) 3 Runoff Depth=2.46" Flow Length=314' 2 Tc=11.3 min CN=74/98 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 5 witout exfiltration Proposed basin 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 23S: Basin 5 Time Precip. Perv.Excess Imp.Excess Runoff (hours) (inches) (inches) (inches) (cfs) 0.00 0.00 0.00 0.00 0.00 1.50 0.06 0.00 0.00 0.01 3.00 0.13 0.00 0.03 0.03 4.50 0.21 0.00 0.07 0.05 6.00 0.29 0.00 0.14 0.07 7.50 0.40 0.00 0.23 0.10 9.00 0.55 0.00 0.36 0.14 10.50 0.77 0.00 0.57 0.25 12.00 1.65 0.20 1.43 2.12 13.50 2.67 0.71 2.44 0.45 15.00 2.89 0.84 2.66 0.23 16.50 3.04 0.93 2.81 0.17 18.00 3.15 1.00 2.91 0.13 19.50 3.23 1.06 3.00 0.11 21.00 3.31 1.11 3.08 0.10 22.50 3.38 1.16 3.15 0.09 24.00 3.44 1.20 3.21 0.08 25.50 3.44 1.20 3.21 0.00 27.00 3.44 1.20 3.21 0.00 28.50 3.44 1.20 3.21 0.00 30.00 3.44 1.20 3.21 0.00 31.50 3.44 1.20 3.21 0.00 33.00 3.44 1.20 3.21 0.00 34.50 3.44 1.20 3.21 0.00 36.00 3.44 1.20 3.21 0.00 37.50 3.44 1.20 3.21 0.00 39.00 3.44 1.20 3.21 0.00 40.50 3.44 1.20 3.21 0.00 42.00 3.44 1.20 3.21 0.00 43.50 3.44 1.20 3.21 0.00 45.00 3.44 1.20 3.21 0.00 46.50 3.44 1.20 3.21 0.00 48.00 3.44 1.20 3.21 0.00 49.50 3.44 1.20 3.21 0.00 51.00 3.44 1.20 3.21 0.00 52.50 3.44 1.20 3.21 0.00 54.00 3.44 1.20 3.21 0.00 55.50 3.44

.20 3.21 0.00 51.00 3.44 1.20 3.21 0.00 52.50 3.44 1.20 3.21 0.00 54.00 3.44 1.20 3.21 0.00 55.50 3.44 1.20 3.21 0.00 57.00 3.44 1.20 3.21 0.00 58.50 3.44 1.20 3.21 0.00 60.00 3.44 1.20 3.21 0.00 61.50 3.44 1.20 3.21 0.00 63.00 3.44 1.20 3.21 0.00 64.50 3.44 1.20 3.21 0.00 66.00 3.44 1.20 3.21 0.00 67.50 3.44 1.20 3.21 0.00 69.00 3.44 1.20 3.21 0.00 70.50 3.44 1.20 3.21 0.00 72.00 3.44 1.20 3.21 0.00

Basin 5 witout exfiltration Proposed basin 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 25S: overland 5-A Runoff = 2.94 cfs @ 12.15 hrs, Volume= 0.243 af, Depth= 1.85" Runoff by SCS TR-20 method, UH=SCS, Split Pervious/Imperv., Time Span= 0.00-72.00 hrs, dt= 0.03 hrs NOAA 24-hr D 2-Year Rainfall=3.44" Area (sf) CN Description 22,200 98 Paved parking, HSG C 46,435 74 >75% Grass cover, Good, HSG C 68,635 82 Weighted Average Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.7 100 0.1200 0.25 Sheet Flow, Grass: Dense n= 0.240 P2= 3.44" 0.1 20 0.0500 3.35 Shallow Concentrated Flow, Grassed Waterway Kv= 15.0 fps 0.4 118 0.0550 4.76 Shallow Concentrated Flow, gutter flow Paved Kv= 20.3 fps 0.4 156 0.0349 6.80 3.82 Pipe Channel, 15.0" Round w/ 8.0" inside fill Area= 0.6 sf Perim= 3.1' r= 0.18' n= 0.013 Corrugated PE, smooth interior 7.6 394 Total Subcatchment 25S: overland 5-A Hydrograph Runoff