09 Stormwater Mgmt Report 122025

NJ DEP 2-hr WQ Rainfall=1.25", P2=4.09" NJA230139 - REV 2 Prepared by Bohler Engineering, PC HydroCAD® 10.20-7a s/n 03478 © 2025 HydroCAD Software Solutions LLC Printed 12/11/2025 Page 13 Pond PP1: Pervious Pavement Hydrograph 0.9 Inflow Primary 0.81 cfs 0.85 Inflow Area=11,761 sf Peak Elev=366.95' Storage=1,014 cf 0.8 0.75 0.7 0.65 0.6 Flow (cfs) 0.55 0.5 0.45 0.4 0.35 0.3 0.25 0.2 0.15 0.1 0.00 cfs 0.05 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)

NJ DEP 2-hr WQ Rainfall=1.25", P2=4.09" NJA230139 - REV 2 Prepared by Bohler Engineering, PC HydroCAD® 10.20-7a s/n 03478 © 2025 HydroCAD Software Solutions LLC Printed 12/11/2025 Page 14 Summary for Link E1: EDA 1A Inflow Area = Inflow = Primary = 84,942 sf, 98.97% Impervious, Inflow Depth = 1.02" for WQ event 5.44 cfs @ 1.05 hrs, Volume= 7,248 cf 5.44 cfs @ 1.05 hrs, Volume= 7,248 cf, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-72.00 hrs, dt= 0.10 hrs Link E1: EDA 1A Hydrograph 5.44 cfs 5.44 cfs Inflow Primary 6 Inflow Area=84,942 sf 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)

NJ DEP 2-hr WQ Rainfall=1.25", P2=4.09" NJA230139 - REV 2 Prepared by Bohler Engineering, PC HydroCAD® 10.20-7a s/n 03478 © 2025 HydroCAD Software Solutions LLC Printed 12/11/2025 Page 15 Summary for Link P1: PDA 1A Inflow Area = Inflow = Primary = 85,378 sf, 95.41% Impervious, Inflow Depth = 0.84" for WQ event 4.50 cfs @ 1.05 hrs, Volume= 6,009 cf 4.50 cfs @ 1.05 hrs, Volume= 6,009 cf, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-72.00 hrs, dt= 0.10 hrs Link P1: PDA 1A Hydrograph 4.50 cfs 4.50 cfs Inflow Primary 5 Inflow Area=85,378 sf 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)

D. CONVEYANCE CALCULATIONS ♦ Pipe Sizing ♦ Pervious Pavement Underdrain Sizing

Hydraflow Storm Sewers Extension for Autodesk® Civil 3D® Plan Outfall Project File: West Orange Storm - Rev 2a.stm Number of lines: 5 Date: 12/11/2025 ‘Storm Sewors v2024,00

Storm Sewer Tabulation Page Station Len IDrng Area Rnoff | Area x C Te Rain |Total |Cap \el Pipe Invert Elev HGL Elev IGrnd / Rim Elev Line ID coeff (l) flow full Line He . Incr | Total Incr Total |intet |syst Size |Slope |Dn Up Dn Up Dn Up (ft) (ac) |(ac) |(C) (min) |(min) |(in/hr) |(cfs) (cfs) |(ft/s) |(in) —|(%) (ft) (ft) (ft) (ft) (ft) (ft) 1 End | 15.000] 0.00 0.34 0.00 | 0.00 0.34 0.0 12.2 6.0 3.66 4.42 4.35 15 0.40 | 364.15 | 364.21 364.92 | 365.06 | 367.37 | 368.08 | SD-3 2 1 51.000} 0.00 0.00 0.00 | 0.00 0.00 0.0 11.7 0.0 1.63 4.14 1.68 15 0.41 | 364.21 | 364.42 | 365.24 | 365.26 | 368.08 | 368.25 | SD-3(2) 3 2 (191.776 0.00 0.00 0.00 | 0.00 0.00 10.0 | 10.4 0.0 1.63 4.07 2.51 15 0.40 | 364.42 | 365.18 | 365.32 | 365.71 368.25 | 368.44 | SD-2 4 3 61.000] 0.00 0.00 0.00 | 0.00 0.00 10.0 | 10.0 0.0 1.49 4.13 2.53 15 0.41 | 365.18 | 365.43 | 365.88 | 365.97 | 368.44 | 368.32 | SD-1 5 1 21.000] 0.34 0.34 0.99 |0.34 0.34 10.0 | 10.0 6.5 2.18 7.00 2.92 15 1.00 | 364.21 | 364.42 | 365.24 | 365.01 368.08 | 367.60 Project File: West Orange Storm - Rev 2a.stm Number of lines: 5 Run Date: 12/11/2025 NOTES: Intensity = 182.59 / (Inlet time + 19.10) * 0.99; Return period =Yrs. 25 ; c= cir e = ellip b = box ‘Storm Sewors v2024,00

Date: Project: Project No: 30 Independence Boulevard, Warren, NJ 07059 (908) 668-8300 7/31/2025 West Orange NJA230139.00 Calculated By: CRA Checked By: TXL Requirement: The capacity of the underdrains must be sufficient to allow the systems to drain within 72 hours. Note: Below drain time calculations ensure underdrain size is sized to allow the system to drain within 72 hours and does not take into consideration outlet control structure. Calculations for drain time considering outlet control section provided in Basin Drain Time calculations in the Appendix of this report. Water Quality Pervious Pavement Drain Time: (Drain Time = Water Quality Design Storm Volume / Underdrain Flow Rate) 1,014 Water Quality Volume (CF) Calculated Drain Time = 1,014 CF / 0.33 CFS * (1 hr / 60 min) * (1 min / 60 sec) = 0.9 hours < 72 hours 100-Year Storm Event Pervious Pavement Drain Time: (100-Yr Design Storm Runoff Volume / Underdrain Flow Rate) 11,054 100-Year Volume (CF) Calculated Drain Time = 11,054 CF / 0.33 CFS * (1 hr / 60 min) * (1 min / 60 sec) = 9.4 hours < 72 hours Manning's Equation Design Parameters: Pipe Diameter, D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Pipe Material . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Slope, s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Flow Depth, y . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Calculations: Cross-Sectional Area, A = D 2 /8 [ θ -sin( θ )] = . . . . . . . . . . . . . . . . . . . . . . . Manning's Coefficient, n . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Hydraulic Radius, R . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Angle, θ = . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Wetted Perimeter, P = θD /2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Flow Depth, y . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Flow Top Width, T = 2[y( D -y)] 1/2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

w Depth, y . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Flow Top Width, T = 2[y( D -y)] 1/2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Gravity Constant, g . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Froude Number, F . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 in PVC 0.20 % FULL 0.20 ft2 0.010 0.13 ft 6.28 radians 1.57 ft 0.50 ft 0.00 ft 32.174 ft/s2 0.00 Subcritical Flow • Flow & Velocity: Flow, Q o = 1.486 · R 2/3s 1/2A . . . . . . . . . . . . . . . . . . . . . . . . n 0.33 cfs 0.21 MGD Velocity, V = Q/A . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . 1.66 fps 1

E. SUPPORTING DOCUMENTS ♦ NOAA Atlas 14 Precipitation Estimate Report

Current Precipitation Adjustment Factors County Atlantic Bergen Burlington Camden Cape May Cumberland Essex Gloucester Hudson Hunterdon Mercer Middlesex Monmouth Morris Ocean Passaic Salem Somerset Sussex Union Warren 2-year Design Storm NOAA Adjustment Current Atlas 14 Factor (inches) (inches) 3.31 1.01 3.34 3.34 1.01 3.37 3.36 0.99 3.33 3.31 1.03 3.41 3.25 1.03 3.35 3.27 1.03 3.37 3.44 1.01 3.47 3.29 1.05 3.45 3.31 1.03 3.41 3.38 1.02 3.45 3.31 1.01 3.34 3.35 1.00 3.35 3.38 1.00 3.38 3.54 1.01 3.58 3.42 1.00 3.42 3.47 1.00 3.47 3.26 1.02 3.33 3.34 1.00 3.34 3.22 1.03 3.32 3.39 1.01 3.42 3.34 1.02 3.41 10-year Design Storm NOAA Adjustment Current Atlas 14 Factor (inches) (inches) 5.16 1.02 5.26 5.07 1.03 5.22 5.18 1.01 5.23 5.06 1.04 5.26 5.07 1.03 5.22 5.09 1.03 5.24 5.22 1.03 5.38 5.05 1.06 5.35 5.02 1.05 5.27 5.00 1.05 5.25 5.01 1.02 5.11 5.12 1.01 5.17 5.23 1.01 5.28 5.24 1.03 5.40 5.33 1.01 5.38 5.23 1.02 5.33 5.00 1.03 5.15 5.01 1.03 5.16 4.70 1.04 4.89 5.17 1.03 5.33 4.89 1.07 5.23 100-year Design Storm NOAA Adjustment Current Atlas 14 Factor (inches) (inches) 8.90 1.03 9.17 8.47 1.06 8.98 8.81 1.04 9.16 8.52 1.05 8.95 8.73 1.04 9.08 8.76 1.01 8.85 8.66 1.06 9.18 8.55 1.06 9.06 8.31 1.09 9.06 8.03 1.13 9.07 8.33 1.04 8.66 8.63 1.03 8.89 8.94 1.02 9.12 8.35 1.06 8.85 9.20 1.03 9.48 8.62 1.05 9.05 8.45 1.03 8.70 8.21 1.09 8.95 7.58 1.07 8.11 8.69 1.06 9.21 7.82 1.15 8.99 County Atlantic Bergen Burlington Camden Cape May Cumberland Essex Gloucester Hudson Hunterdon Mercer Middlesex Monmouth Morris Ocean Passaic Salem Somerset Sussex Union Warren 9/2023