251203_42 ERW_Stormwater Report

NOAA 24-hr D 10-Year Rainfall=6.37" 250903_42 ERW Waystone - Future Rainfall Prepared by Colliers Engineering & Design HydroCAD® 10.20-5c s/n 04431 © 2023 HydroCAD Software Solutions LLC Printed 11/25/2025 Page 20 Summary for Subcatchment EDA-2 (PERV.): Runoff = 1.63 cfs @ 12.14 hrs, Volume= Routed to Reach DP2-EX : 0.123 af, Depth= 3.50" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs NOAA 24-hr D 10-Year Rainfall=6.37" Area (ac) 0.423 0.423 CN 74 Description >75% Grass cover, Good, HSG C 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 7.1 100 0.0410 0.24 Sheet Flow, Grass: Short n= 0.150 P2= 3.44" 0.1 21 0.1050 5.22 Shallow Concentrated Flow, Unpaved Kv= 16.1 fps 7.2 121 Total Subcatchment EDA-2 (PERV.): Hydrograph Runoff Flow (cfs) 1.63 cfs NOAA 24-hr D 10-Year Rainfall=6.37" Runoff Area=0.423 ac Runoff Volume=0.123 af Runoff Depth=3.50" Flow Length=121' Tc=7.2 min CN=74 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)

250903_42 ERW Waystone - Future Rainfall NOAA 24-hr D 10-Year Rainfall=6.37" Prepared by Colliers Engineering & Design HydroCAD® 10.20-5c s/n 04431 © 2023 HydroCAD Software Solutions LLC Hydrograph for Subcatchment EDA-2 (PERV.): Time Precip. Excess (hours) (inches) (inches) 0.00 0.00 0.00 1.00 0.07 0.00 2.00 0.15 0.00 3.00 0.24 0.00 4.00 0.33 0.00 5.00 0.44 0.00 6.00 0.54 0.00 7.00 0.67 0.00 8.00 0.83 0.00 9.00 1.01 0.02 10.00 1.26 0.08 11.00 1.66 0.20 12.00 3.05 0.94 13.00 4.71 2.14 14.00 5.11 2.45 15.00 5.36 2.65 16.00 5.54 2.80 17.00 5.70 2.93 18.00 5.83 3.04 19.00 5.93 3.13 20.00 6.04 3.22 21.00 6.13 3.29 22.00 6.22 3.37 23.00 6.30 3.44 24.00 6.37 3.50 25.00 6.37 3.50 26.00 6.37 3.50 27.00 6.37 3.50 28.00 6.37 3.50 29.00 6.37 3.50 30.00 6.37 3.50 31.00 6.37 3.50 32.00 6.37 3.50 33.00 6.37 3.50 34.00 6.37 3.50 35.00 6.37 3.50 36.00 6.37 3.50 37.00 6.37 3.50 38.00 6.37 3.50 39.00 6.37 3.50 40.00 6.37 3.50 41.00 6.37 3.50 42.00 6.37 3.50 43.00 6.37 3.50 44.00 6.37 3.50 45.00 6.37 3.50 46.00 6.37 3.50 47.00 6.37 3.50 48.00 6.37 3.50 49.00 6.37 3.50 50.00 6.37 3.50 51.00 6.37 3.50 Runoff (cfs) 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.01 0.03 0.08 0.77 0.21 0.11 0.07 0.06 0.05 0.04 0.04 0.04 0.03 0.03 0.03 0.03 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Time Precip. Excess (hours) (inches) (inches) 52.00 6.37 3.50 53.00 6.37 3.50 54.00 6.37 3.50 55.00 6.37 3.50 56.00 6.37 3.50 57.00 6.37 3.50 58.00 6.37 3.50 59.00 6.37 3.50 60.00 6.37 3.50 61.00 6.37 3.50 62.00 6.37 3.50 63.00 6.37 3.50 64.00 6.37 3.50 65.00 6.37 3.50 66.00 6.37 3.50 67.00 6.37 3.50 68.00 6.37 3.50 69.00 6.37 3.50 70.00 6.37 3.50 71.00 6.37 3.50 72.00 6.37 3.50 Runoff (cfs) 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Printed 11/25/2025 Page 21

NOAA 24-hr D 10-Year Rainfall=6.37" 250903_42 ERW Waystone - Future Rainfall Prepared by Colliers Engineering & Design HydroCAD® 10.20-5c s/n 04431 © 2023 HydroCAD Software Solutions LLC Printed 11/25/2025 Page 22 Summary for Reach DP1-EX: Inflow Area = Inflow = Outflow = 2.669 ac, 11.97% Impervious, Inflow Depth = 3.81" for 10-Year event 8.17 cfs @ 12.20 hrs, Volume= 0.848 af 8.17 cfs @ 12.20 hrs, Volume= 0.848 af, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind+Trans method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Reach DP1-EX: Hydrograph 9 8.17 cfs 8 Inflow Outflow 8.17 cfs Inflow Area=2.669 ac 7 Flow (cfs) 6 5 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)

NOAA 24-hr D 10-Year Rainfall=6.37" 250903_42 ERW Waystone - Future Rainfall Printed 11/25/2025 Page 23 Prepared by Colliers Engineering & Design HydroCAD® 10.20-5c s/n 04431 © 2023 HydroCAD Software Solutions LLC Hydrograph for Reach DP1-EX: Time (hours) 0.00 1.00 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 10.00 11.00 12.00 13.00 14.00 15.00 16.00 17.00 18.00 19.00 20.00 21.00 22.00 23.00 24.00 25.00 26.00 27.00 28.00 29.00 30.00 31.00 32.00 33.00 34.00 35.00 36.00 37.00 38.00 39.00 40.00 41.00 42.00 43.00 44.00 45.00 46.00 47.00 48.00 49.00 50.00 51.00 Inflow Elevation (cfs) (feet) 0.00 0.01 0.02 0.02 0.03 0.03 0.03 0.04 0.07 0.12 0.25 0.57 4.14 1.47 0.71 0.49 0.40 0.33 0.27 0.24 0.23 0.21 0.20 0.18 0.17 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Outflow (cfs) 0.00 0.01 0.02 0.02 0.03 0.03 0.03 0.04 0.07 0.12 0.25 0.57 4.14 1.47 0.71 0.49 0.40 0.33 0.27 0.24 0.23 0.21 0.20 0.18 0.17 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Time (hours) 52.00 53.00 54.00 55.00 56.00 57.00 58.00 59.00 60.00 61.00 62.00 63.00 64.00 65.00 66.00 67.00 68.00 69.00 70.00 71.00 72.00 Inflow (cfs) 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Elevation (feet) Outflow (cfs) 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

NOAA 24-hr D 10-Year Rainfall=6.37" 250903_42 ERW Waystone - Future Rainfall Prepared by Colliers Engineering & Design HydroCAD® 10.20-5c s/n 04431 © 2023 HydroCAD Software Solutions LLC Printed 11/25/2025 Page 24 Summary for Reach DP2-EX: Inflow Area = Inflow = Outflow = 0.423 ac, 0.00% Impervious, Inflow Depth = 3.50" for 10-Year event 1.63 cfs @ 12.14 hrs, Volume= 0.123 af 1.63 cfs @ 12.14 hrs, Volume= 0.123 af, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind+Trans method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Reach DP2-EX: Hydrograph Inflow Outflow 1.63 cfs Flow (cfs) 1.63 cfs Inflow Area=0.423 ac 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)

NOAA 24-hr D 10-Year Rainfall=6.37" 250903_42 ERW Waystone - Future Rainfall Printed 11/25/2025 Page 25 Prepared by Colliers Engineering & Design HydroCAD® 10.20-5c s/n 04431 © 2023 HydroCAD Software Solutions LLC Hydrograph for Reach DP2-EX: Time (hours) 0.00 1.00 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 10.00 11.00 12.00 13.00 14.00 15.00 16.00 17.00 18.00 19.00 20.00 21.00 22.00 23.00 24.00 25.00 26.00 27.00 28.00 29.00 30.00 31.00 32.00 33.00 34.00 35.00 36.00 37.00 38.00 39.00 40.00 41.00 42.00 43.00 44.00 45.00 46.00 47.00 48.00 49.00 50.00 51.00 Inflow Elevation (cfs) (feet) 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.01 0.03 0.08 0.77 0.21 0.11 0.07 0.06 0.05 0.04 0.04 0.04 0.03 0.03 0.03 0.03 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Outflow (cfs) 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.01 0.03 0.08 0.77 0.21 0.11 0.07 0.06 0.05 0.04 0.04 0.04 0.03 0.03 0.03 0.03 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Time (hours) 52.00 53.00 54.00 55.00 56.00 57.00 58.00 59.00 60.00 61.00 62.00 63.00 64.00 65.00 66.00 67.00 68.00 69.00 70.00 71.00 72.00 Inflow (cfs) 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Elevation (feet) Outflow (cfs) 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

250903_42 ERW Waystone - Future Rainfall NOAA 24-hr D 100-Year Rainfall=11.52" Prepared by Colliers Engineering & Design HydroCAD® 10.20-5c s/n 04431 © 2023 HydroCAD Software Solutions LLC Printed 11/25/2025 Page 26 Time span=0.00-72.00 hrs, dt=0.05 hrs, 1441 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment EDA-1 (IMPERV): Runoff Area=13,913 sf 100.00% Impervious Runoff Depth=11.28" Flow Length=275' Tc=2.8 min CN=98 Runoff=3.85 cfs 0.300 af Subcatchment EDA-1 (PERV): Runoff Area=102,351 sf 0.00% Impervious Runoff Depth=8.17" Flow Length=501' Tc=13.1 min CN=74 Runoff=16.95 cfs 1.599 af Subcatchment EDA-2 (PERV.): Runoff Area=0.423 ac 0.00% Impervious Runoff Depth=8.17" Flow Length=121' Tc=7.2 min CN=74 Runoff=3.70 cfs 0.288 af Reach DP1-EX: Inflow=18.32 cfs 1.899 af Outflow=18.32 cfs 1.899 af Reach DP2-EX: Inflow=3.70 cfs 0.288 af Outflow=3.70 cfs 0.288 af Total Runoff Area = 3.092 ac Runoff Volume = 2.187 af Average Runoff Depth = 8.49" 89.67% Pervious = 2.773 ac 10.33% Impervious = 0.319 ac

250903_42 ERW Waystone - Future Rainfall NOAA 24-hr D 100-Year Rainfall=11.52" Prepared by Colliers Engineering & Design HydroCAD® 10.20-5c s/n 04431 © 2023 HydroCAD Software Solutions LLC Printed 11/25/2025 Page 27 Summary for Subcatchment EDA-1 (IMPERV): Runoff = 3.85 cfs @ 12.09 hrs, Volume= Routed to Reach DP1-EX : 0.300 af, Depth=11.28" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs NOAA 24-hr D 100-Year Rainfall=11.52" Area (sf) 8,137 5,776 13,913 13,913 CN 98 98 98 Description Paved parking, HSG C Roofs, HSG C Weighted Average 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 1.1 78 0.0150 1.21 Sheet Flow, Smooth surfaces n= 0.011 P2= 3.44" 1.0 12 0.0800 0.20 Sheet Flow, Grass: Short n= 0.150 P2= 3.44" 0.7 185 0.0830 4.64 Shallow Concentrated Flow, Unpaved Kv= 16.1 fps 2.8 275 Total Subcatchment EDA-1 (IMPERV): Hydrograph Runoff 4 3.85 cfs NOAA 24-hr D 100-Year Rainfall=11.52" Runoff Area=13,913 sf Runoff Volume=0.300 af Runoff Depth=11.28" Flow Length=275' Tc=2.8 min CN=98 Flow (cfs) 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)

250903_42 ERW Waystone - Future Rainfall NOAA 24-hr D 100-Year Rainfall=11.52" Prepared by Colliers Engineering & Design HydroCAD® 10.20-5c s/n 04431 © 2023 HydroCAD Software Solutions LLC Hydrograph for Subcatchment EDA-1 (IMPERV): Time Precip. Excess (hours) (inches) (inches) 0.00 0.00 0.00 1.00 0.13 0.03 2.00 0.28 0.13 3.00 0.43 0.26 4.00 0.60 0.41 5.00 0.79 0.59 6.00 0.98 0.77 7.00 1.21 1.00 8.00 1.49 1.28 9.00 1.83 1.60 10.00 2.28 2.06 11.00 2.99 2.76 12.00 5.52 5.28 13.00 8.53 8.29 14.00 9.24 9.00 15.00 9.69 9.45 16.00 10.03 9.78 17.00 10.31 10.07 18.00 10.54 10.30 19.00 10.73 10.49 20.00 10.92 10.67 21.00 11.09 10.84 22.00 11.24 11.00 23.00 11.39 11.15 24.00 11.52 11.28 25.00 11.52 11.28 26.00 11.52 11.28 27.00 11.52 11.28 28.00 11.52 11.28 29.00 11.52 11.28 30.00 11.52 11.28 31.00 11.52 11.28 32.00 11.52 11.28 33.00 11.52 11.28 34.00 11.52 11.28 35.00 11.52 11.28 36.00 11.52 11.28 37.00 11.52 11.28 38.00 11.52 11.28 39.00 11.52 11.28 40.00 11.52 11.28 41.00 11.52 11.28 42.00 11.52 11.28 43.00 11.52 11.28 44.00 11.52 11.28 45.00 11.52 11.28 46.00 11.52 11.28 47.00 11.52 11.28 48.00 11.52 11.28 49.00 11.52 11.28 50.00 11.52 11.28 51.00 11.52 11.28 Runoff (cfs) 0.00 0.02 0.04 0.05 0.05 0.06 0.06 0.08 0.10 0.11 0.17 0.31 2.32 0.35 0.18 0.12 0.10 0.08 0.07 0.06 0.06 0.05 0.05 0.04 0.04 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Time Precip. Excess (hours) (inches) (inches) 52.00 11.52 11.28 53.00 11.52 11.28 54.00 11.52 11.28 55.00 11.52 11.28 56.00 11.52 11.28 57.00 11.52 11.28 58.00 11.52 11.28 59.00 11.52 11.28 60.00 11.52 11.28 61.00 11.52 11.28 62.00 11.52 11.28 63.00 11.52 11.28 64.00 11.52 11.28 65.00 11.52 11.28 66.00 11.52 11.28 67.00 11.52 11.28 68.00 11.52 11.28 69.00 11.52 11.28 70.00 11.52 11.28 71.00 11.52 11.28 72.00 11.52 11.28 Runoff (cfs) 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Printed 11/25/2025 Page 28

NOAA 24-hr D 100-Year Rainfall=11.52" 250903_42 ERW Waystone - Future Rainfall Prepared by Colliers Engineering & Design HydroCAD® 10.20-5c s/n 04431 © 2023 HydroCAD Software Solutions LLC Printed 11/25/2025 Page 29 Summary for Subcatchment EDA-1 (PERV): Runoff = 16.95 cfs @ 12.21 hrs, Volume= Routed to Reach DP1-EX : 1.599 af, Depth= 8.17" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs NOAA 24-hr D 100-Year Rainfall=11.52" Area (sf) 102,351 102,351 CN 74 Description >75% Grass cover, Good, HSG C 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 10.9 100 0.0140 0.15 Sheet Flow, Grass: Short n= 0.150 P2= 3.44" 2.2 401 0.0350 3.01 Shallow Concentrated Flow, Unpaved Kv= 16.1 fps 13.1 501 Total Subcatchment EDA-1 (PERV): Hydrograph Runoff 18 16.95 cfs 17 NOAA 24-hr D 100-Year Rainfall=11.52" Runoff Area=102,351 sf Runoff Volume=1.599 af Runoff Depth=8.17" Flow Length=501' Tc=13.1 min CN=74 16 15 14 13 Flow (cfs) 12 11 10 9 8 7 6 5 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)