J_2024 05 09_West Orange Stormwater Management Plan

Post-Developed (O-1A) West Orange HydroCAD_Post Table of Contents Prepared by Burns & McDonnell Printed 5/13/2024 HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC 178 180 182 184 186 189 192 195 198 Reach 4R: TD-02 Reach 5R: TD-03 Reach 6R: TD-04 Pond 7P: O-1A Pond 12P: SD-03, SD-04, SD-05 Pond 15P: SD-06, SD-07, SD-08 Pond 16P: SD-09, SD-10 Pond 20P: SD-11, SD-12 Pond 23P: SD-01, SD-02 100-Year_Current Event 201 Node Listing 203 Subcat 4S: PO-DA B 205 Subcat 6S: PO-DA D 207 Subcat 8S: PO-DA F 209 Subcat 10S: PO-DA H 211 Subcat 13S: PO-DA K 213 Subcat 14S: PO-DA L 215 Reach 3R: TD-01 217 Reach 4R: TD-02 219 Reach 5R: TD-03 221 Reach 6R: TD-04 223 Pond 7P: O-1A 225 Pond 12P: SD-03, SD-04, SD-05 228 Pond 15P: SD-06, SD-07, SD-08 231 Pond 16P: SD-09, SD-10 234 Pond 20P: SD-11, SD-12 237 Pond 23P: SD-01, SD-02 100-Year_Future Event 240 Node Listing 242 Subcat 4S: PO-DA B 244 Subcat 6S: PO-DA D 246 Subcat 8S: PO-DA F 248 Subcat 10S: PO-DA H 250 Subcat 13S: PO-DA K 252 Subcat 14S: PO-DA L 254 Reach 3R: TD-01 256 Reach 4R: TD-02 258 Reach 5R: TD-03 260 Reach 6R: TD-04 262 Pond 7P: O-1A 264 Pond 12P: SD-03, SD-04, SD-05 267 Pond 15P: SD-06, SD-07, SD-08 270 Pond 16P: SD-09, SD-10 273 Pond 20P: SD-11, SD-12 276 Pond 23P: SD-01, SD-02

Post-Developed (O-1A) West Orange HydroCAD_Post Printed 5/13/2024 Page 2 Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Rainfall Events Listing (selected events) Event# 1 2 3 4 5 6 7 Event Name Storm Type WQ 2-Year_Current 2-Year_Future 10-Year_Current 10-Year_Future 100-Year_Current 100-Year_Future NJ DEP 2-hr NOAA 24-hr NOAA 24-hr NOAA 24-hr NOAA 24-hr NOAA 24-hr NOAA 24-hr Curve Mode Duration (hours) B/B Depth (inches) D D D D D D Default Default Default Default Default Default Default 2.00 24.00 24.00 24.00 24.00 24.00 24.00 1 1 1 1 1 1 1 1.25 3.45 4.07 5.37 6.36 9.23 11.58 AMC 2 2 2 2 2 2 2 P2 (inches) 3.42 3.45 4.07 3.45 4.07 3.45 4.07

Post-Developed (O-1A) West Orange HydroCAD_Post Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Area Listing (selected nodes) Area (acres) CN Description (subcatchment-numbers) 0.212 1.147 0.031 0.019 1.409 80 73 98 85 75 >75% Grass cover, Good, HSG D (4S, 6S, 8S, 10S, 13S, 14S) Brush, Good, HSG D (4S, 6S, 8S, 10S, 13S, 14S) Impervious, Pavement, HSG D (13S) Yard Stone/Gravel Pad, HSG D (4S, 14S) TOTAL AREA Printed 5/13/2024 Page 3

Post-Developed (O-1A) West Orange HydroCAD_Post Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Soil Listing (selected nodes) Area (acres) Soil Group 0.000 0.000 0.000 1.409 0.000 1.409 HSG A HSG B HSG C HSG D Other Subcatchment Numbers 4S, 6S, 8S, 10S, 13S, 14S TOTAL AREA Printed 5/13/2024 Page 4

Post-Developed (O-1A) West Orange HydroCAD_Post Printed 5/13/2024 Page 5 Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Ground Covers (selected nodes) HSG-A (acres) HSG-B (acres) HSG-C (acres) HSG-D (acres) Other (acres) Total (acres) Ground Cover Subcatchment Numbers 0.000 0.000 0.000 0.212 0.000 0.212 0.000 0.000 0.000 1.147 0.000 1.147 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.031 0.019 1.409 0.000 0.000 0.000 0.031 0.019 1.409 >75% Grass cover, Good 4S, 6S, 8S, 10S, 13S, 14S Brush, Good 4S, 6S, 8S, 10S, 13S, 14S Impervious, Pavement 13S Yard Stone/Gravel Pad 4S, 14S TOTAL AREA

Post-Developed (O-1A) West Orange HydroCAD_Post NJ DEP 2-hr WQ Rainfall=1.25", P2=3.42" Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Printed 5/13/2024 Page 6 Time span=0.00-24.00 hrs, dt=0.0100 hrs, 2401 points Runoff by SCS TR-20 method, UH=SCS, Weighted-Q Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Runoff Area=28,575 sf 0.00% Impervious Runoff Depth=0.07" Flow Length=298' Tc=13.4 min CN=WQ Runoff=0.08 cfs 0.004 af Subcatchment 4S: PO-DA B Runoff Area=6,403 sf 0.00% Impervious Runoff Depth=0.13" Flow Length=85' Slope=0.1773 '/' Tc=7.6 min CN=WQ Runoff=0.04 cfs 0.002 af Subcatchment 6S: PO-DA D Runoff Area=3,746 sf 0.00% Impervious Runoff Depth=0.10" Flow Length=66' Slope=0.2264 '/' Tc=5.6 min CN=WQ Runoff=0.02 cfs 0.001 af Subcatchment 8S: PO-DA F Runoff Area=10,281 sf 0.00% Impervious Runoff Depth=0.07" Flow Length=82' Slope=0.1736 '/' Tc=7.5 min CN=WQ Runoff=0.03 cfs 0.001 af Subcatchment 10S: PO-DA H Subcatchment 13S: PO-DA K Runoff Area=4,400 sf 30.68% Impervious Runoff Depth=0.39" Flow Length=239' Tc=14.4 min CN=WQ Runoff=0.08 cfs 0.003 af Subcatchment 14S: PO-DA L Runoff Area=7,972 sf 0.00% Impervious Runoff Depth=0.08" Flow Length=116' Tc=11.1 min CN=WQ Runoff=0.03 cfs 0.001 af Reach 3R: TD-01 Avg. Flow Depth=0.02' Max Vel=1.55 fps Inflow=0.04 cfs 0.002 af n=0.012 L=67.2' S=0.0298 '/' Capacity=30.28 cfs Outflow=0.04 cfs 0.002 af Reach 4R: TD-02 Avg. Flow Depth=0.01' Max Vel=1.24 fps Inflow=0.02 cfs 0.001 af n=0.012 L=34.0' S=0.0279 '/' Capacity=29.34 cfs Outflow=0.02 cfs 0.001 af Reach 5R: TD-03 Avg. Flow Depth=0.03' Max Vel=0.72 fps Inflow=0.03 cfs 0.001 af n=0.012 L=133.7' S=0.0044 '/' Capacity=11.66 cfs Outflow=0.03 cfs 0.001 af Reach 6R: TD-04 Avg. Flow Depth=0.02' Max Vel=1.04 fps Inflow=0.03 cfs 0.001 af n=0.012 L=54.6' S=0.0163 '/' Capacity=22.41 cfs Outflow=0.03 cfs 0.001 af Pond 7P: O-1A Inflow=0.18 cfs 0.010 af Primary=0.18 cfs 0.010 af Pond 12P: SD-03, SD-04, SD-05 Peak Elev=596.07' Storage=5 cf Inflow=0.07 cfs 0.004 af Outflow=0.07 cfs 0.004 af Pond 15P: SD-06, SD-07, SD-08 Peak Elev=594.05' Storage=2 cf Inflow=0.08 cfs 0.004 af Outflow=0.08 cfs 0.004 af Pond 16P: SD-09, SD-10 Peak Elev=592.96' Storage=7 cf Inflow=0.10 cfs 0.006 af Outflow=0.10 cfs 0.006 af Pond 20P: SD-11, SD-12 Peak Elev=591.14' Storage=12 cf Inflow=0.11

utflow=0.08 cfs 0.004 af Pond 16P: SD-09, SD-10 Peak Elev=592.96' Storage=7 cf Inflow=0.10 cfs 0.006 af Outflow=0.10 cfs 0.006 af Pond 20P: SD-11, SD-12 Peak Elev=591.14' Storage=12 cf Inflow=0.11 cfs 0.007 af Outflow=0.11 cfs 0.007 af Pond 23P: SD-01, SD-02 Peak Elev=597.15' Storage=85 cf Inflow=0.08 cfs 0.004 af Outflow=0.05 cfs 0.002 af

Post-Developed (O-1A) West Orange HydroCAD_Post NJ DEP 2-hr WQ Rainfall=1.25", P2=3.42" Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Printed 5/13/2024 Page 7 Total Runoff Area = 1.409 ac Runoff Volume = 0.012 af Average Runoff Depth = 0.10" 97.80% Pervious = 1.378 ac 2.20% Impervious = 0.031 ac

Post-Developed (O-1A) NJ DEP 2-hr WQ Rainfall=1.25", P2=3.42" West Orange HydroCAD_Post Printed 5/13/2024 Page 8 Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Summary for Subcatchment 4S: PO-DA B Runoff = 0.08 cfs @ 1.31 hrs, Volume= Routed to Pond 23P : SD-01, SD-02 0.004 af, Depth= 0.07" Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-24.00 hrs, dt= 0.0100 hrs NJ DEP 2-hr WQ Rainfall=1.25", P2=3.42" Area (sf) 1,873 610 26,092 28,575 28,575 * CN 80 85 73 Description >75% Grass cover, Good, HSG D Yard Stone/Gravel Pad, HSG D Brush, Good, HSG D Weighted Average 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 11.4 100 0.0900 0.15 Sheet Flow, Sheet Flow Woods: Light underbrush n= 0.400 P2= 3.42" 0.3 64 0.1920 3.07 Shallow Concentrated Flow, Shallow Concentrated Flow Short Grass Pasture Kv= 7.0 fps 1.7 134 0.0094 1.34 8.07 Channel Flow, North Channel Area= 6.0 sf Perim= 9.3' r= 0.65' n= 0.080 Earth, long dense weeds 13.4 298 Total Subcatchment 4S: PO-DA B Hydrograph 0.085 Runoff 0.08 cfs 0.08 NJ DEP 2-hr WQ Rainfall=1.25" P2=3.42" Runoff Area=28,575 sf Runoff Volume=0.004 af Runoff Depth=0.07" Flow Length=298' Tc=13.4 min CN=WQ 0.075 0.07 0.065 0.06 Flow (cfs) 0.055 0.05 0.045 0.04 0.035 0.03 0.025 0.02 0.015 0.01 0.005 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Time (hours) 15 16 17 18 19 20 21 22 23 24

Post-Developed (O-1A) West Orange HydroCAD_Post NJ DEP 2-hr WQ Rainfall=1.25", P2=3.42" Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Hydrograph for Subcatchment 4S: PO-DA B Time Precip. Excess (hours) (inches) (inches) 0.00 0.00 0.00 0.50 0.10 0.00 1.00 0.63 0.00 1.50 1.15 0.05 2.00 1.25 0.07 2.50 1.25 0.07 3.00 1.25 0.07 3.50 1.25 0.07 4.00 1.25 0.07 4.50 1.25 0.07 5.00 1.25 0.07 5.50 1.25 0.07 6.00 1.25 0.07 6.50 1.25 0.07 7.00 1.25 0.07 7.50 1.25 0.07 8.00 1.25 0.07 8.50 1.25 0.07 9.00 1.25 0.07 9.50 1.25 0.07 10.00 1.25 0.07 10.50 1.25 0.07 11.00 1.25 0.07 11.50 1.25 0.07 12.00 1.25 0.07 12.50 1.25 0.07 13.00 1.25 0.07 13.50 1.25 0.07 14.00 1.25 0.07 14.50 1.25 0.07 15.00 1.25 0.07 15.50 1.25 0.07 16.00 1.25 0.07 16.50 1.25 0.07 17.00 1.25 0.07 17.50 1.25 0.07 18.00 1.25 0.07 18.50 1.25 0.07 19.00 1.25 0.07 19.50 1.25 0.07 20.00 1.25 0.07 20.50 1.25 0.07 21.00 1.25 0.07 21.50 1.25 0.07 22.00 1.25 0.07 22.50 1.25 0.07 23.00 1.25 0.07 23.50 1.25 0.07 24.00 1.25 0.07 Runoff (cfs) 0.00 0.00 0.00 0.06 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 0.00 0.00 0.00 0.00 0.00 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 5/13/2024 Page 9