Report 4 13 2026

29906 15 Ridgeway West Orange Final Revision 3 Prepared by Ensurplan Inc Printed 4/20/2026 HydroCAD® 10.20-8a s/n 11646 © 2025 HydroCAD Software Solutions LLC Page 50 Rainfall Events Listing (selected events) Event# Event Storm Type Curve Mode Duration B/B Depth AMC P2 Name (hours) (inches) (inches) 1 2-Year-2020 NOAA 24-hr D Default 24.00 1 3.47 2 3.47 2 10-Year-2020 NOAA 24-hr D Default 24.00 1 5.38 2 3.47 3 100-Year-2020 NOAA 24-hr D Default 24.00 1 9.18 2 3.47 4 2-Year-2050 NOAA 24-hr D Default 24.00 1 4.09 2 4.09 5 10-Year-2050 NOAA 24-hr D Default 24.00 1 6.37 2 4.09 6 100-Year-2050 NOAA 24-hr D Default 24.00 1 11.52 2 4.09 7 WQDS NJ DEP 2-hr Default 2.00 1 1.25 2 3.44

29906 15 Ridgeway West Orange Final NOAA 24-hr D 2-Year-2020 Rainfall=3.47", P2=3.47" Prepared by Ensurplan Inc Printed 4/20/2026 HydroCAD® 10.20-8a s/n 11646 © 2025 HydroCAD Software Solutions LLC Page 51 Summary for Reach 12R: Study Point At Inlet Inflow Area = 0.390 ac,100.00% Impervious, Inflow Depth = 2.22" for 2-Year-2020 event Inflow = 0.19 cfs @ 12.17 hrs, Volume= 0.072 af Outflow = 0.19 cfs @ 12.17 hrs, Volume= 0.072 af, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind+Trans method, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Reach 12R: Study Point At Inlet Hydrograph 0.21 0.2 0.19 cfs Inflow Outflow 0.19 0.18 0.17 Inflow Area=0.390 ac 0.16 0.15 0.14 0.13 Flow (cfs) 0.12 0.11 0.1 0.09 0.08 0.07 0.06 0.05 0.04 0.03 0.02 0.01 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 Time (hours)

29906 15 Ridgeway West Orange Final NOAA 24-hr D 10-Year-2020 Rainfall=5.38", P2=3.47" Prepared by Ensurplan Inc Printed 4/20/2026 HydroCAD® 10.20-8a s/n 11646 © 2025 HydroCAD Software Solutions LLC Page 52 Summary for Reach 12R: Study Point At Inlet Inflow Area = 0.390 ac,100.00% Impervious, Inflow Depth = 3.95" for 10-Year-2020 event Inflow = 0.66 cfs @ 12.27 hrs, Volume= 0.128 af Outflow = 0.66 cfs @ 12.27 hrs, Volume= 0.128 af, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind+Trans method, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Reach 12R: Study Point At Inlet Hydrograph 0.7 0.66 cfs Inflow Outflow 0.65 0.6 Inflow Area=0.390 ac 0.55 0.5 0.45 Flow (cfs) 0.4 0.35 0.3 0.25 0.2 0.15 0.1 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 Time (hours)

29906 15 Ridgeway West Orange Fina NOAA 24-hr D 100-Year-2020 Rainfall=9.18", P2=3.47" Prepared by Ensurplan Inc Printed 4/20/2026 HydroCAD® 10.20-8a s/n 11646 © 2025 HydroCAD Software Solutions LLC Page 53 Summary for Reach 12R: Study Point At Inlet Inflow Area = 0.390 ac,100.00% Impervious, Inflow Depth = 7.61" for 100-Year-2020 event Inflow = 1.80 cfs @ 12.19 hrs, Volume= 0.247 af Outflow = 1.80 cfs @ 12.19 hrs, Volume= 0.247 af, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind+Trans method, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Reach 12R: Study Point At Inlet Hydrograph 2 1.80 cfs Inflow Outflow Inflow Area=0.390 ac 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 Time (hours)

29906 15 Ridgeway West Orange Final NOAA 24-hr D 2-Year-2050 Rainfall=4.09", P2=4.09" Prepared by Ensurplan Inc Printed 4/20/2026 HydroCAD® 10.20-8a s/n 11646 © 2025 HydroCAD Software Solutions LLC Page 54 Summary for Reach 12R: Study Point At Inlet Inflow Area = 0.390 ac,100.00% Impervious, Inflow Depth = 2.76" for 2-Year-2050 event Inflow = 0.26 cfs @ 12.52 hrs, Volume= 0.090 af Outflow = 0.26 cfs @ 12.52 hrs, Volume= 0.090 af, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind+Trans method, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Reach 12R: Study Point At Inlet Hydrograph 0.28 0.26 cfs Inflow Outflow 0.26 0.24 Inflow Area=0.390 ac 0.22 0.2 0.18 Flow (cfs) 0.16 0.14 0.12 0.1 0.08 0.06 0.04 0.02 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 Time (hours)

29906 15 Ridgeway West Orange Final NOAA 24-hr D 10-Year-2050 Rainfall=6.37", P2=4.09" Prepared by Ensurplan Inc Printed 4/20/2026 HydroCAD® 10.20-8a s/n 11646 © 2025 HydroCAD Software Solutions LLC Page 55 Summary for Reach 12R: Study Point At Inlet Inflow Area = 0.390 ac,100.00% Impervious, Inflow Depth = 4.89" for 10-Year-2050 event Inflow = 0.90 cfs @ 12.24 hrs, Volume= 0.159 af Outflow = 0.90 cfs @ 12.24 hrs, Volume= 0.159 af, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind+Trans method, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Reach 12R: Study Point At Inlet Hydrograph 1 0.90 cfs Inflow Outflow Inflow Area=0.390 ac Flow (cfs) 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 Time (hours)

29906 15 Ridgeway West Orange Fin NOAA 24-hr D 100-Year-2050 Rainfall=11.52", P2=4.09" Prepared by Ensurplan Inc Printed 4/20/2026 HydroCAD® 10.20-8a s/n 11646 © 2025 HydroCAD Software Solutions LLC Page 56 Summary for Reach 12R: Study Point At Inlet Inflow Area = 0.390 ac,100.00% Impervious, Inflow Depth = 9.88" for 100-Year-2050 event Inflow = 2.33 cfs @ 12.19 hrs, Volume= 0.321 af Outflow = 2.33 cfs @ 12.19 hrs, Volume= 0.321 af, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind+Trans method, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Reach 12R: Study Point At Inlet Hydrograph 2.33 cfs Inflow Outflow Inflow Area=0.390 ac 2 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 Time (hours)

29906 15 Ridgeway West Orange Final Revisi NJ DEP 2-hr WQDS Rainfall=1.25", P2=3.44" Prepared by Ensurplan Inc Printed 4/20/2026 HydroCAD® 10.20-8a s/n 11646 © 2025 HydroCAD Software Solutions LLC Page 57 Summary for Reach 12R: Study Point At Inlet Inflow Area = 0.390 ac,100.00% Impervious, Inflow Depth = 0.82" for WQDS event Inflow = 0.16 cfs @ 1.16 hrs, Volume= 0.027 af Outflow = 0.16 cfs @ 1.16 hrs, Volume= 0.027 af, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind+Trans method, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Reach 12R: Study Point At Inlet Hydrograph 0.18 0.16 cfs 0.17 Inflow Outflow 0.16 0.15 Inflow Area=0.390 ac 0.14 0.13 0.12 0.11 Flow (cfs) 0.1 0.09 0.08 0.07 0.06 0.05 0.04 0.03 0.02 0.01 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 Time (hours)