251203_42 ERW_Stormwater Report

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 61 Summary for Pond BASIN: Inflow Area = 2.619 ac, 32.35% Impervious, Inflow Depth = 4.76" for 25-Year event Inflow = 11.97 cfs @ 12.10 hrs, Volume= 1.040 af Outflow = 5.17 cfs @ 12.29 hrs, Volume= 1.040 af, Atten= 57%, Lag= 11.5 min Discarded = 0.39 cfs @ 12.29 hrs, Volume= 0.443 af Primary = 4.78 cfs @ 12.29 hrs, Volume= 0.597 af Routed to Reach DP1-PR : Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Peak Elev= 17.61' @ 12.29 hrs Surf.Area= 0.168 ac Storage= 0.308 af Plug-Flow detention time= 91.4 min calculated for 1.039 af (100% of inflow) Center-of-Mass det. time= 91.6 min ( 880.3 - 788.7 ) Volume #1A Invert 15.00' Avail.Storage 0.199 af #2A 15.75' 0.341 af 0.539 af Storage Description 51.42'W x 141.93'L x 5.00'H Field A 0.838 af Overall - 0.341 af Embedded = 0.497 af x 40.0% Voids ADS_StormTech MC-3500 d +Cap x 133 Inside #1 Effective Size= 70.4"W x 45.0"H => 15.33 sf x 7.17'L = 110.0 cf Overall Size= 77.0"W x 45.0"H x 7.50'L with 0.33' Overlap 133 Chambers in 7 Rows Cap Storage= 14.9 cf x 2 x 7 rows = 208.6 cf Total Available Storage Storage Group A created with Chamber Wizard Device #1 Routing Primary Invert 15.89' #2 Primary 16.73' #3 Primary 18.75' #4 Discarded 15.00' Outlet Devices 14.0" W x 3.5" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads 20.0" W x 5.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads 1.0' long x 0.5' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 Coef. (English) 2.80 2.92 3.08 3.30 3.32 1.000 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 13.00' Discarded OutFlow Max=0.39 cfs @ 12.29 hrs HW=17.61' (Free Discharge) 4=Exfiltration ( Controls 0.39 cfs) Primary OutFlow Max=4.77 cfs @ 12.29 hrs HW=17.61' (Free Discharge) 1=Orifice/Grate (Orifice Controls 2.05 cfs @ 6.03 fps) 2=Orifice/Grate (Orifice Controls 2.72 cfs @ 3.92 fps) 3=Broad-Crested Rectangular Weir ( Controls 0.00 cfs)

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 62 Pond BASIN: - Chamber Wizard Field A Chamber Model = ADS_StormTechMC-3500 d +Cap (ADS StormTech® MC-3500 d rev 03/14 with Cap volume) Effective Size= 70.4"W x 45.0"H => 15.33 sf x 7.17'L = 110.0 cf Overall Size= 77.0"W x 45.0"H x 7.50'L with 0.33' Overlap Cap Storage= 14.9 cf x 2 x 7 rows = 208.6 cf 77.0" Wide + 9.0" Spacing = 86.0" C-C Row Spacing 19 Chambers/Row x 7.17' Long +1.85' Cap Length x 2 = 139.93' Row Length +12.0" End Stone x 2 = 141.93' Base Length 7 Rows x 77.0" Wide + 9.0" Spacing x 6 + 12.0" Side Stone x 2 = 51.42' Base Width 9.0" Stone Base + 45.0" Chamber Height + 6.0" Stone Cover = 5.00' Field Height 133 Chambers x 110.0 cf + 14.9 cf Cap Volume x 2 x 7 Rows = 14,832.2 cf Chamber Storage 36,487.8 cf Field - 14,832.2 cf Chambers = 21,655.6 cf Stone x 40.0% Voids = 8,662.3 cf Stone Storage Chamber Storage + Stone Storage = 23,494.5 cf = 0.539 af Overall Storage Efficiency = 64.4% Overall System Size = 141.93' x 51.42' x 5.00' 133 Chambers 1,351.4 cy Field 802.1 cy Stone

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 63 Pond BASIN: Hydrograph 11.97 cfs Inflow Area=2.619 ac Peak Elev=17.61' Storage=0.308 af 13 12 11 10 Flow (cfs) 9 8 7 5.17 cfs 6 5 4.78 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 25-Year Rainfall=6.44" Printed 12/3/2025 Page 64 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 0.45 2.82 0.52 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 0.002 15.02 0.003 15.04 0.022 15.32 0.284 17.43 0.115 16.20 0.086 16.00 0.076 15.93 0.069 15.88 0.044 15.66 0.004 15.05 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 4.63 0.90 0.39 0.28 0.24 0.22 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 Discarded (cfs) 0.00 0.05 0.08 0.15 0.20 0.37 0.27 0.25 0.25 0.24 0.22 0.17 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 Primary (cfs) 0.00 0.00 0.00 0.00 0.00 4.25 0.63 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 25-Year Rainfall=6.44" Printed 12/3/2025 Page 65 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 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 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 66

251202_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 12/3/2025 Page 67 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=8.71" Flow Length=203' Tc=5.9 min CN=78 Runoff=2.86 cfs 0.219 af Subcatchment PR 1B-I: Runoff Area=36,906 sf 100.00% Impervious Runoff Depth=11.28" Flow Length=136' Tc=1.5 min CN=98 Runoff=10.27 cfs 0.796 af Subcatchment PR 1B-P: Runoff Area=77,195 sf 0.00% Impervious Runoff Depth=8.85" Flow Length=195' Tc=7.7 min CN=79 Runoff=16.19 cfs 1.307 af Subcatchment PR 2-P: Runoff Area=7,405 sf 0.00% Impervious Runoff Depth=8.44" Flow Length=84' Slope=0.0833 '/' Tc=4.6 min CN=76 Runoff=1.64 cfs 0.120 af Reach 10R: Inflow=23.63 cfs 2.103 af Outflow=23.63 cfs 2.103 af Reach DP1-PR: Inflow=14.42 cfs 1.772 af Outflow=14.42 cfs 1.772 af Reach DP2-PR: Inflow=1.64 cfs 0.120 af Outflow=1.64 cfs 0.120 af Pond BASIN: Peak Elev=19.87' Storage=0.531 af Inflow=23.63 cfs 2.103 af Discarded=0.58 cfs 0.550 af Primary=12.86 cfs 1.553 af Outflow=13.44 cfs 2.103 af Total Runoff Area = 3.092 ac Runoff Volume = 2.442 af Average Runoff Depth = 9.48" 72.60% Pervious = 2.244 ac 27.40% Impervious = 0.847 ac

NOAA 24-hr D 100-Year Rainfall=11.52" 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 68 Summary for Subcatchment PR 1A-P: Runoff = 2.86 cfs @ 12.13 hrs, Volume= Routed to Reach DP1-PR : 0.219 af, Depth= 8.71" 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) 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 3 2.86 cfs NOAA 24-hr D 100-Year Rainfall=11.52" Runoff Area=13,167 sf Runoff Volume=0.219 af Runoff Depth=8.71" Flow Length=203' Tc=5.9 min CN=78 Flow (cfs) 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 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 PR 1A-P: Time Precip. Excess (hours) (inches) (inches) 0.00 0.00 0.00 1.00 0.13 0.00 2.00 0.28 0.00 3.00 0.43 0.00 4.00 0.60 0.00 5.00 0.79 0.02 6.00 0.98 0.05 7.00 1.21 0.12 8.00 1.49 0.23 9.00 1.83 0.39 10.00 2.28 0.65 11.00 2.99 1.13 12.00 5.52 3.16 13.00 8.53 5.88 14.00 9.24 6.54 15.00 9.69 6.97 16.00 10.03 7.29 17.00 10.31 7.56 18.00 10.54 7.77 19.00 10.73 7.96 20.00 10.92 8.13 21.00 11.09 8.30 22.00 11.24 8.45 23.00 11.39 8.59 24.00 11.52 8.71 25.00 11.52 8.71 26.00 11.52 8.71 27.00 11.52 8.71 28.00 11.52 8.71 29.00 11.52 8.71 30.00 11.52 8.71 31.00 11.52 8.71 32.00 11.52 8.71 33.00 11.52 8.71 34.00 11.52 8.71 35.00 11.52 8.71 36.00 11.52 8.71 37.00 11.52 8.71 38.00 11.52 8.71 39.00 11.52 8.71 40.00 11.52 8.71 41.00 11.52 8.71 42.00 11.52 8.71 43.00 11.52 8.71 44.00 11.52 8.71 45.00 11.52 8.71 46.00 11.52 8.71 47.00 11.52 8.71 48.00 11.52 8.71 49.00 11.52 8.71 50.00 11.52 8.71 51.00 11.52 8.71 Runoff (cfs) 0.00 0.00 0.00 0.00 0.00 0.01 0.01 0.03 0.04 0.06 0.10 0.20 1.58 0.32 0.16 0.11 0.09 0.08 0.06 0.06 0.05 0.05 0.04 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 8.71 53.00 11.52 8.71 54.00 11.52 8.71 55.00 11.52 8.71 56.00 11.52 8.71 57.00 11.52 8.71 58.00 11.52 8.71 59.00 11.52 8.71 60.00 11.52 8.71 61.00 11.52 8.71 62.00 11.52 8.71 63.00 11.52 8.71 64.00 11.52 8.71 65.00 11.52 8.71 66.00 11.52 8.71 67.00 11.52 8.71 68.00 11.52 8.71 69.00 11.52 8.71 70.00 11.52 8.71 71.00 11.52 8.71 72.00 11.52 8.71 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 69