Drainage Report

NOAA 24-hr D 13 100-Year Rainfall=8.66" 12 11 Runoff Area=99,084 sf 10 Runoff Volume=1.392 af Flow (cfs) 9 8 Runoff Depth=7.34" 7 Flow Length=314' 6 Tc=11.3 min 5 4 CN=74/98 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 5 witout exfiltration Proposed basin 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 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 0.15 0.00 0.04 0.08 3.00 0.33 0.00 0.17 0.14 4.50 0.52 0.00 0.34 0.18 6.00 0.74 0.00 0.54 0.21 7.50 1.01 0.03 0.80 0.31 9.00 1.37 0.11 1.16 0.43 10.50 1.94 0.32 1.71 0.82 12.00 4.15 1.71 3.91 6.47 13.50 6.72 3.80 6.48 1.27 15.00 7.29 4.29 7.05 0.65 16.50 7.65 4.61 7.41 0.48 18.00 7.92 4.85 7.68 0.35 19.50 8.14 5.05 7.90 0.31 21.00 8.33 5.23 8.09 0.28 22.50 8.51 5.38 8.27 0.24 24.00 8.66 5.52 8.42 0.21 25.50 8.66 5.52 8.42 0.00 27.00 8.66 5.52 8.42 0.00 28.50 8.66 5.52 8.42 0.00 30.00 8.66 5.52 8.42 0.00 31.50 8.66 5.52 8.42 0.00 33.00 8.66 5.52 8.42 0.00 34.50 8.66 5.52 8.42 0.00 36.00 8.66 5.52 8.42 0.00 37.50 8.66 5.52 8.42 0.00 39.00 8.66 5.52 8.42 0.00 40.50 8.66 5.52 8.42 0.00 42.00 8.66 5.52 8.42 0.00 43.50 8.66 5.52 8.42 0.00 45.00 8.66 5.52 8.42 0.00 46.50 8.66 5.52 8.42 0.00 48.00 8.66 5.52 8.42 0.00 49.50 8.66 5.52 8.42 0.00 51.00 8.66 5.52 8.42 0.00 52.50 8.66 5.52 8.42 0.00 54.00 8.66 5.52 8.42 0.00 55.50 8.66

.52 8.42 0.00 51.00 8.66 5.52 8.42 0.00 52.50 8.66 5.52 8.42 0.00 54.00 8.66 5.52 8.42 0.00 55.50 8.66 5.52 8.42 0.00 57.00 8.66 5.52 8.42 0.00 58.50 8.66 5.52 8.42 0.00 60.00 8.66 5.52 8.42 0.00 61.50 8.66 5.52 8.42 0.00 63.00 8.66 5.52 8.42 0.00 64.50 8.66 5.52 8.42 0.00 66.00 8.66 5.52 8.42 0.00 67.50 8.66 5.52 8.42 0.00 69.00 8.66 5.52 8.42 0.00 70.50 8.66 5.52 8.42 0.00 72.00 8.66 5.52 8.42 0.00

Basin 5 witout exfiltration Proposed basin 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 Summary for Subcatchment 25S: overland 5-A [47] Hint: Peak is 272% of capacity of segment #4 Runoff = 10.39 cfs @ 12.15 hrs, Volume= 0.848 af, Depth= 6.46" 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 100-Year Rainfall=8.66" 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

Basin 5 witout exfiltration Proposed basin 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 37 Subcatchment 25S: overland 5-A Hydrograph Runoff 11 10.39 cfs 10 NOAA 24-hr D 9 100-Year Rainfall=8.66" 8 Runoff Area=68,635 sf 7 Runoff Volume=0.848 af Flow (cfs) 6 Runoff Depth=6.46" 5 Flow Length=394' 4 Tc=7.6 min 3 CN=74/98 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 5 witout exfiltration Proposed basin 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 38 Hydrograph for Subcatchment 25S: overland 5-A Time Precip. Perv.Excess Imp.Excess Runoff (hours) (inches) (inches) (inches) (cfs) 0.00 0.00 0.00 0.00 0.00 1.50 0.15 0.00 0.04 0.03 3.00 0.33 0.00 0.17 0.05 4.50 0.52 0.00 0.34 0.06 6.00 0.74 0.00 0.54 0.08 7.50 1.01 0.03 0.80 0.14 9.00 1.37 0.11 1.16 0.21 10.50 1.94 0.32 1.71 0.46 12.00 4.15 1.71 3.91 5.13 13.50 6.72 3.80 6.48 0.80 15.00 7.29 4.29 7.05 0.42 16.50 7.65 4.61 7.41 0.32 18.00 7.92 4.85 7.68 0.23 19.50 8.14 5.05 7.90 0.20 21.00 8.33 5.23 8.09 0.18 22.50 8.51 5.38 8.27 0.16 24.00 8.66 5.52 8.42 0.14 25.50 8.66 5.52 8.42 0.00 27.00 8.66 5.52 8.42 0.00 28.50 8.66 5.52 8.42 0.00 30.00 8.66 5.52 8.42 0.00 31.50 8.66 5.52 8.42 0.00 33.00 8.66 5.52 8.42 0.00 34.50 8.66 5.52 8.42 0.00 36.00 8.66 5.52 8.42 0.00 37.50 8.66 5.52 8.42 0.00 39.00 8.66 5.52 8.42 0.00 40.50 8.66 5.52 8.42 0.00 42.00 8.66 5.52 8.42 0.00 43.50 8.66 5.52 8.42 0.00 45.00 8.66 5.52 8.42 0.00 46.50 8.66 5.52 8.42 0.00 48.00 8.66 5.52 8.42 0.00 49.50 8.66 5.52 8.42 0.00 51.00 8.66 5.52 8.42 0.00 52.50 8.66 5.52 8.42 0.00 54.00 8.66 5.52 8.42 0.00 55.50 8.66

5.52 8.42 0.00 51.00 8.66 5.52 8.42 0.00 52.50 8.66 5.52 8.42 0.00 54.00 8.66 5.52 8.42 0.00 55.50 8.66 5.52 8.42 0.00 57.00 8.66 5.52 8.42 0.00 58.50 8.66 5.52 8.42 0.00 60.00 8.66 5.52 8.42 0.00 61.50 8.66 5.52 8.42 0.00 63.00 8.66 5.52 8.42 0.00 64.50 8.66 5.52 8.42 0.00 66.00 8.66 5.52 8.42 0.00 67.50 8.66 5.52 8.42 0.00 69.00 8.66 5.52 8.42 0.00 70.50 8.66 5.52 8.42 0.00 72.00 8.66 5.52 8.42 0.00

Basin 5 witout exfiltration Proposed basin 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 39 Summary for Subcatchment 26S: pre-dev basin 5 Runoff = 18.50 cfs @ 12.19 hrs, Volume= 1.616 af, Depth= 5.04" 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 100-Year Rainfall=8.66" Area (sf) CN Description 167,719 70 Woods, Good, HSG C Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 10.1 100 0.1200 0.16 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 3.44" 1.4 174 0.1670 2.04 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 11.5 274 Total Subcatchment 26S: pre-dev basin 5 Hydrograph 20 Runoff 18.50 cfs 19 18 NOAA 24-hr D 17 16 100-Year Rainfall=8.66" 15 14 Runoff Area=167,719 sf 13 Runoff Volume=1.616 af 12 Flow (cfs) 11 Runoff Depth=5.04"

Runoff Volume=1.616 af 12 Flow (cfs) 11 Runoff Depth=5.04" 10 9 Flow Length=274' 8 7 Tc=11.5 min 6 5 CN=70/0 4 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 5 witout exfiltration Proposed basin 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 40 Hydrograph for Subcatchment 26S: pre-dev 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 0.15 0.00 0.00 0.00 3.00 0.33 0.00 0.00 0.00 4.50 0.52 0.00 0.00 0.00 6.00 0.74 0.00 0.00 0.00 7.50 1.01 0.01 0.00 0.04 9.00 1.37 0.06 0.00 0.19 10.50 1.94 0.22 0.00 0.61 12.00 4.15 1.43 0.00 7.50 13.50 6.72 3.39 0.00 1.87 15.00 7.29 3.86 0.00 0.97 16.50 7.65 4.16 0.00 0.72 18.00 7.92 4.40 0.00 0.53 19.50 8.14 4.58 0.00 0.47 21.00 8.33 4.75 0.00 0.42 22.50 8.51 4.90 0.00 0.37 24.00 8.66 5.04 0.00 0.33 25.50 8.66 5.04 0.00 0.00 27.00 8.66 5.04 0.00 0.00 28.50 8.66 5.04 0.00 0.00 30.00 8.66 5.04 0.00 0.00 31.50 8.66 5.04 0.00 0.00 33.00 8.66 5.04 0.00 0.00 34.50 8.66 5.04 0.00 0.00 36.00 8.66 5.04 0.00 0.00 37.50 8.66 5.04 0.00 0.00 39.00 8.66 5.04 0.00 0.00 40.50 8.66 5.04 0.00 0.00 42.00 8.66 5.04 0.00 0.00 43.50 8.66 5.04 0.00 0.00 45.00 8.66 5.04 0.00 0.00 46.50 8.66 5.04 0.00 0.00 48.00 8.66 5.04 0.00 0.00 49.50 8.66 5.04 0.00 0.00 51.00 8.66 5.04 0.00 0.00 52.50 8.66 5.04 0.00 0.00 54.00 8.66 5.04 0.00 0.00 55.50 8.66