251203_42 ERW_Stormwater Report

NOAA 24-hr D 10-Year Rainfall=6.37" 251202_42 ERW Waystone - Future Rainfall Prepared by Colliers Engineering & Design HydroCAD® 10.20-5c s/n 04431 © 2023 HydroCAD Software Solutions LLC Printed 12/3/2025 Page 42 Pond BASIN: Hydrograph 11.81 cfs Inflow Area=2.619 ac Peak Elev=17.58' Storage=0.304 af 13 12 11 10 Flow (cfs) 9 8 7 5.09 cfs 6 5 4.70 cfs 4 3 2 0.39 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) Inflow Outflow Discarded Primary

251202_42 ERW Waystone - Future Rainfall NOAA 24-hr D 10-Year Rainfall=6.37" Printed 12/3/2025 Page 43 Prepared by Colliers Engineering & Design HydroCAD® 10.20-5c s/n 04431 © 2023 HydroCAD Software Solutions LLC Hydrograph for Pond BASIN: Time (hours) 0.00 2.50 5.00 7.50 10.00 12.50 15.00 17.50 20.00 22.50 25.00 27.50 30.00 32.50 35.00 37.50 40.00 42.50 45.00 47.50 50.00 52.50 55.00 57.50 60.00 62.50 65.00 67.50 70.00 Inflow (cfs) 0.00 0.05 0.08 0.16 0.44 2.78 0.51 0.32 0.24 0.20 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 Storage Elevation (acre-feet) (feet) 0.000 15.00 0.001 15.01 0.001 15.02 0.003 15.04 0.021 15.31 0.281 17.40 0.114 16.19 0.086 16.00 0.076 15.92 0.069 15.88 0.044 15.65 0.003 15.04 0.000 15.00 0.000 15.00 0.000 15.00 0.000 15.00 0.000 15.00 0.000 15.00 0.000 15.00 0.000 15.00 0.000 15.00 0.000 15.00 0.000 15.00 0.000 15.00 0.000 15.00 0.000 15.00 0.000 15.00 0.000 15.00 0.000 15.00 Outflow (cfs) 0.00 0.05 0.08 0.15 0.20 4.55 0.89 0.38 0.27 0.24 0.22 0.15 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 Discarded (cfs) 0.00 0.05 0.08 0.15 0.20 0.37 0.27 0.25 0.25 0.24 0.22 0.15 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 Primary (cfs) 0.00 0.00 0.00 0.00 0.00 4.18 0.62 0.13 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

251202_42 ERW Waystone - Future Rainfall NOAA 24-hr D 10-Year Rainfall=6.37" Printed 12/3/2025 Page 44 Prepared by Colliers Engineering & Design HydroCAD® 10.20-5c s/n 04431 © 2023 HydroCAD Software Solutions LLC Stage-Discharge for Pond BASIN: Elevation (feet) 15.00 15.05 15.10 15.15 15.20 15.25 15.30 15.35 15.40 15.45 15.50 15.55 15.60 15.65 15.70 15.75 15.80 15.85 15.90 15.95 16.00 16.05 16.10 16.15 16.20 16.25 16.30 16.35 16.40 16.45 16.50 16.55 16.60 16.65 16.70 16.75 16.80 16.85 16.90 16.95 17.00 17.05 17.10 17.15 17.20 17.25 17.30 17.35 17.40 17.45 17.50 17.55 Discharge (cfs) 0.00 0.17 0.18 0.18 0.19 0.19 0.19 0.20 0.20 0.21 0.21 0.22 0.22 0.22 0.23 0.23 0.24 0.24 0.25 0.30 0.39 0.50 0.62 0.76 0.91 1.02 1.11 1.19 1.27 1.34 1.41 1.47 1.53 1.59 1.65 1.71 1.85 2.02 2.23 2.45 2.70 2.96 3.24 3.53 3.78 3.99 4.19 4.37 4.54 4.70 4.85 5.00 Discarded (cfs) 0.00 0.17 0.18 0.18 0.19 0.19 0.19 0.20 0.20 0.21 0.21 0.22 0.22 0.22 0.23 0.23 0.24 0.24 0.24 0.25 0.25 0.26 0.26 0.27 0.27 0.27 0.28 0.28 0.29 0.29 0.30 0.30 0.30 0.31 0.31 0.32 0.32 0.33 0.33 0.33 0.34 0.34 0.35 0.35 0.35 0.36 0.36 0.37 0.37 0.38 0.38 0.38 Primary (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 0.06 0.14 0.24 0.36 0.50 0.64 0.74 0.83 0.91 0.98 1.05 1.11 1.17 1.23 1.28 1.33 1.40 1.53 1.70 1.90 2.12 2.36 2.62 2.89 3.18 3.42 3.63 3.82 4.00 4.16 4.32 4.47 4.62 Elevation (feet) 17.60 17.65 17.70 17.75 17.80 17.85 17.90 17.95 18.00 18.05 18.10 18.15 18.20 18.25 18.30 18.35 18.40 18.45 18.50 18.55 18.60 18.65 18.70 18.75 18.80 18.85 18.90 18.95 19.00 19.05 19.10 19.15 19.20 19.25 19.30 19.35 19.40 19.45 19.50 19.55 19.60 19.65 19.70 19.75 19.80 19.85 19.90 19.95 20.00 Discharge (cfs) 5.15 5.28 5.42 5.55 5.68 5.80 5.92 6.04 6.16 6.27 6.38 6.49 6.60 6.71 6.81 6.91 7.01 7.11 7.21 7.31 7.40 7.50 7.59 7.68 7.80 7.95 8.11 8.29 8.48 8.68 8.90 9.12 9.36 9.61 9.87 10.14 10.43 10.74 11.06 11.39 11.69 12.01 12.33 12.65 12.98 13.31 13.65 13.99 14.34 Discarded (cfs) 0.39 0.39 0.40 0.40 0.41 0.41 0.41 0.42 0.42 0.43 0.43 0.43 0.44 0.44 0.45 0.45 0.46 0.46 0.46 0.47 0.47 0.48 0.48 0.49 0.49 0.49 0.50 0.50 0.51 0.51 0.52 0.52 0.52 0.53 0.53 0.54 0.54 0.54 0.55 0.55 0.56 0.56 0.57 0.57 0.57 0.58 0.58 0.59 0.59 Primary (cfs) 4.76 4.89 5.02 5.15 5.27 5.39 5.51 5.62 5.74 5.85 5.95 6.06 6.16 6.26 6.36 6.46 6.56 6.65 6.75 6.84 6.93 7.02 7.11 7.20 7.31 7.46

0.55 0.55 0.56 0.56 0.57 0.57 0.57 0.58 0.58 0.59 0.59 Primary (cfs) 4.76 4.89 5.02 5.15 5.27 5.39 5.51 5.62 5.74 5.85 5.95 6.06 6.16 6.26 6.36 6.46 6.56 6.65 6.75 6.84 6.93 7.02 7.11 7.20 7.31 7.46 7.62 7.79 7.97 8.17 8.38 8.60 8.83 9.08 9.34 9.60 9.89 10.19 10.51 10.83 11.14 11.45 11.76 12.08 12.41 12.73 13.07 13.41 13.75

NOAA 24-hr D 10-Year Rainfall=6.37" 251202_42 ERW Waystone - Future Rainfall Prepared by Colliers Engineering & Design HydroCAD® 10.20-5c s/n 04431 © 2023 HydroCAD Software Solutions LLC Stage-Area-Storage for Pond BASIN: Elevation (feet) 15.00 15.05 15.10 15.15 15.20 15.25 15.30 15.35 15.40 15.45 15.50 15.55 15.60 15.65 15.70 15.75 15.80 15.85 15.90 15.95 16.00 16.05 16.10 16.15 16.20 16.25 16.30 16.35 16.40 16.45 16.50 16.55 16.60 16.65 16.70 16.75 16.80 16.85 16.90 16.95 17.00 17.05 17.10 17.15 17.20 17.25 17.30 17.35 17.40 17.45 17.50 17.55 Surface (acres) 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 Storage (acre-feet) 0.000 0.003 0.007 0.010 0.013 0.017 0.020 0.023 0.027 0.030 0.034 0.037 0.040 0.044 0.047 0.050 0.058 0.065 0.072 0.079 0.086 0.094 0.101 0.108 0.115 0.122 0.129 0.136 0.143 0.151 0.158 0.165 0.172 0.179 0.186 0.193 0.199 0.206 0.213 0.220 0.227 0.234 0.241 0.247 0.254 0.261 0.267 0.274 0.281 0.287 0.294 0.300 Elevation (feet) 17.60 17.65 17.70 17.75 17.80 17.85 17.90 17.95 18.00 18.05 18.10 18.15 18.20 18.25 18.30 18.35 18.40 18.45 18.50 18.55 18.60 18.65 18.70 18.75 18.80 18.85 18.90 18.95 19.00 19.05 19.10 19.15 19.20 19.25 19.30 19.35 19.40 19.45 19.50 19.55 19.60 19.65 19.70 19.75 19.80 19.85 19.90 19.95 20.00 Surface (acres) 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 0.168 Storage (acre-feet) 0.307 0.313 0.320 0.326 0.332 0.339 0.345 0.351 0.357 0.363 0.369 0.375 0.381 0.387 0.393 0.399 0.405 0.410 0.416 0.421 0.427 0.432 0.438 0.443 0.448 0.453 0.458 0.463 0.467 0.472 0.476 0.480 0.484 0.488 0.492 0.495 0.499 0.502 0.506 0.509 0.513 0.516 0.519 0.523 0.526 0.529 0.533 0.536 0.539 Printed 12/3/2025 Page 45

251202_42 ERW Waystone - Future Rainfall NOAA 24-hr D 25-Year Rainfall=6.44" Prepared by Colliers Engineering & Design HydroCAD® 10.20-5c s/n 04431 © 2023 HydroCAD Software Solutions LLC Printed 12/3/2025 Page 46 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 PR 1A-P: Runoff Area=13,167 sf 0.00% Impervious Runoff Depth=3.97" Flow Length=203' Tc=5.9 min CN=78 Runoff=1.36 cfs 0.100 af Subcatchment PR 1B-I: Runoff Area=36,906 sf 100.00% Impervious Runoff Depth=6.20" Flow Length=136' Tc=1.5 min CN=98 Runoff=5.73 cfs 0.438 af Subcatchment PR 1B-P: Runoff Area=77,195 sf 0.00% Impervious Runoff Depth=4.07" Flow Length=195' Tc=7.7 min CN=79 Runoff=7.74 cfs 0.602 af Subcatchment PR 2-P: Runoff Area=7,405 sf 0.00% Impervious Runoff Depth=3.76" Flow Length=84' Slope=0.0833 '/' Tc=4.6 min CN=76 Runoff=0.76 cfs 0.053 af Reach 10R: Inflow=11.97 cfs 1.040 af Outflow=11.97 cfs 1.040 af Reach DP1-PR: Inflow=5.46 cfs 0.697 af Outflow=5.46 cfs 0.697 af Reach DP2-PR: Inflow=0.76 cfs 0.053 af Outflow=0.76 cfs 0.053 af Pond BASIN: Peak Elev=17.61' Storage=0.308 af Inflow=11.97 cfs 1.040 af Discarded=0.39 cfs 0.443 af Primary=4.78 cfs 0.597 af Outflow=5.17 cfs 1.040 af Total Runoff Area = 3.092 ac Runoff Volume = 1.193 af Average Runoff Depth = 4.63" 72.60% Pervious = 2.244 ac 27.40% Impervious = 0.847 ac

NOAA 24-hr D 25-Year Rainfall=6.44" 251202_42 ERW Waystone - Future Rainfall Prepared by Colliers Engineering & Design HydroCAD® 10.20-5c s/n 04431 © 2023 HydroCAD Software Solutions LLC Printed 12/3/2025 Page 47 Summary for Subcatchment PR 1A-P: Runoff = 1.36 cfs @ 12.13 hrs, Volume= Routed to Reach DP1-PR : 0.100 af, Depth= 3.97" 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 25-Year Rainfall=6.44" Area (sf) 9,975 3,192 13,167 13,167 CN 74 89 78 Description >75% Grass cover, Good, HSG C Gravel roads, HSG C Weighted Average 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.6 100 0.0725 0.30 Sheet Flow, Grass: Short n= 0.150 P2= 3.44" 0.3 103 0.1090 5.32 Shallow Concentrated Flow, Unpaved Kv= 16.1 fps 5.9 203 Total Subcatchment PR 1A-P: Hydrograph Runoff 1.36 cfs NOAA 24-hr D 25-Year Rainfall=6.44" Runoff Area=13,167 sf Runoff Volume=0.100 af Runoff Depth=3.97" Flow Length=203' Tc=5.9 min CN=78 Flow (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)

251202_42 ERW Waystone - Future Rainfall NOAA 24-hr D 25-Year Rainfall=6.44" Prepared by Colliers Engineering & Design HydroCAD® 10.20-5c s/n 04431 © 2023 HydroCAD Software Solutions LLC Hydrograph for Subcatchment PR 1A-P: 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 0.34 0.00 5.00 0.44 0.00 6.00 0.55 0.00 7.00 0.68 0.00 8.00 0.84 0.02 9.00 1.02 0.06 10.00 1.28 0.14 11.00 1.67 0.31 12.00 3.09 1.19 13.00 4.77 2.51 14.00 5.16 2.85 15.00 5.42 3.07 16.00 5.60 3.23 17.00 5.76 3.37 18.00 5.89 3.48 19.00 6.00 3.58 20.00 6.10 3.67 21.00 6.20 3.75 22.00 6.29 3.83 23.00 6.37 3.90 24.00 6.44 3.97 25.00 6.44 3.97 26.00 6.44 3.97 27.00 6.44 3.97 28.00 6.44 3.97 29.00 6.44 3.97 30.00 6.44 3.97 31.00 6.44 3.97 32.00 6.44 3.97 33.00 6.44 3.97 34.00 6.44 3.97 35.00 6.44 3.97 36.00 6.44 3.97 37.00 6.44 3.97 38.00 6.44 3.97 39.00 6.44 3.97 40.00 6.44 3.97 41.00 6.44 3.97 42.00 6.44 3.97 43.00 6.44 3.97 44.00 6.44 3.97 45.00 6.44 3.97 46.00 6.44 3.97 47.00 6.44 3.97 48.00 6.44 3.97 49.00 6.44 3.97 50.00 6.44 3.97 51.00 6.44 3.97 Runoff (cfs) 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.01 0.02 0.03 0.08 0.71 0.16 0.08 0.06 0.05 0.04 0.03 0.03 0.03 0.03 0.02 0.02 0.02 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 6.44 3.97 53.00 6.44 3.97 54.00 6.44 3.97 55.00 6.44 3.97 56.00 6.44 3.97 57.00 6.44 3.97 58.00 6.44 3.97 59.00 6.44 3.97 60.00 6.44 3.97 61.00 6.44 3.97 62.00 6.44 3.97 63.00 6.44 3.97 64.00 6.44 3.97 65.00 6.44 3.97 66.00 6.44 3.97 67.00 6.44 3.97 68.00 6.44 3.97 69.00 6.44 3.97 70.00 6.44 3.97 71.00 6.44 3.97 72.00 6.44 3.97 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 12/3/2025 Page 48

251202_42 ERW Waystone - Future Rainfall NOAA 24-hr D 25-Year Rainfall=6.44" Prepared by Colliers Engineering & Design HydroCAD® 10.20-5c s/n 04431 © 2023 HydroCAD Software Solutions LLC Printed 12/3/2025 Page 49 Summary for Subcatchment PR 1B-I: Runoff = 5.73 cfs @ 12.07 hrs, Volume= Routed to Reach 10R : 0.438 af, Depth= 6.20" 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 25-Year Rainfall=6.44" Area (sf) 21,449 15,457 36,906 36,906 CN 98 98 98 Description Roofs, HSG C Paved parking, HSG C Weighted Average 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 1.2 100 0.0200 1.43 Sheet Flow, Smooth surfaces n= 0.011 P2= 3.44" 0.3 36 0.0097 2.00 Shallow Concentrated Flow, Paved Kv= 20.3 fps 1.5 136 Total Subcatchment PR 1B-I: Hydrograph Runoff 6 5.73 cfs NOAA 24-hr D 25-Year Rainfall=6.44" Runoff Area=36,906 sf Runoff Volume=0.438 af Runoff Depth=6.20" Flow Length=136' Tc=1.5 min CN=98 5 Flow (cfs) 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)

251202_42 ERW Waystone - Future Rainfall NOAA 24-hr D 25-Year Rainfall=6.44" Prepared by Colliers Engineering & Design HydroCAD® 10.20-5c s/n 04431 © 2023 HydroCAD Software Solutions LLC Hydrograph for Subcatchment PR 1B-I: Time Precip. Excess (hours) (inches) (inches) 0.00 0.00 0.00 1.00 0.07 0.00 2.00 0.15 0.04 3.00 0.24 0.10 4.00 0.34 0.18 5.00 0.44 0.26 6.00 0.55 0.36 7.00 0.68 0.48 8.00 0.84 0.63 9.00 1.02 0.81 10.00 1.28 1.06 11.00 1.67 1.45 12.00 3.09 2.85 13.00 4.77 4.53 14.00 5.16 4.93 15.00 5.42 5.18 16.00 5.60 5.37 17.00 5.76 5.52 18.00 5.89 5.65 19.00 6.00 5.76 20.00 6.10 5.86 21.00 6.20 5.96 22.00 6.29 6.05 23.00 6.37 6.13 24.00 6.44 6.20 25.00 6.44 6.20 26.00 6.44 6.20 27.00 6.44 6.20 28.00 6.44 6.20 29.00 6.44 6.20 30.00 6.44 6.20 31.00 6.44 6.20 32.00 6.44 6.20 33.00 6.44 6.20 34.00 6.44 6.20 35.00 6.44 6.20 36.00 6.44 6.20 37.00 6.44 6.20 38.00 6.44 6.20 39.00 6.44 6.20 40.00 6.44 6.20 41.00 6.44 6.20 42.00 6.44 6.20 43.00 6.44 6.20 44.00 6.44 6.20 45.00 6.44 6.20 46.00 6.44 6.20 47.00 6.44 6.20 48.00 6.44 6.20 49.00 6.44 6.20 50.00 6.44 6.20 51.00 6.44 6.20 Runoff (cfs) 0.00 0.02 0.04 0.06 0.07 0.08 0.09 0.11 0.14 0.17 0.25 0.46 3.67 0.51 0.26 0.18 0.15 0.12 0.10 0.09 0.08 0.08 0.07 0.07 0.05 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 6.44 6.20 53.00 6.44 6.20 54.00 6.44 6.20 55.00 6.44 6.20 56.00 6.44 6.20 57.00 6.44 6.20 58.00 6.44 6.20 59.00 6.44 6.20 60.00 6.44 6.20 61.00 6.44 6.20 62.00 6.44 6.20 63.00 6.44 6.20 64.00 6.44 6.20 65.00 6.44 6.20 66.00 6.44 6.20 67.00 6.44 6.20 68.00 6.44 6.20 69.00 6.44 6.20 70.00 6.44 6.20 71.00 6.44 6.20 72.00 6.44 6.20 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 12/3/2025 Page 50