29906 15 Ridgeway West Orange 5 26 26 HydroCAD Report

29906 15 Ridgeway West Orange Seco NOAA 24-hr D 2-Year-2020 Rainfall=3.47", P2=3.47" Prepared by Ensurplan Inc Printed 5/26/2026 HydroCAD® 10.20-8a s/n 11646 © 2025 HydroCAD Software Solutions LLC Page 37 Summary for Pond 12P: Front Yard Basin Inflow Area = 0.305 ac, 50.99% Impervious, Inflow Depth = 2.16" for 2-Year-2020 event Inflow = 0.87 cfs @ 12.09 hrs, Volume= 0.055 af Outflow = 0.14 cfs @ 12.50 hrs, Volume= 0.055 af, Atten= 84%, Lag= 24.9 min Discarded = 0.02 cfs @ 12.50 hrs, Volume= 0.027 af Primary = 0.12 cfs @ 12.50 hrs, Volume= 0.027 af Routed to Reach 12R : Study Point At Inlet Routing by Stor-Ind method, Time Span= 0.00-36.00 hrs, dt= 0.01 hrs / 2 Peak Elev= 564.31' @ 12.50 hrs Surf.Area= 1,086 sf Storage= 921 cf Plug-Flow detention time= 173.8 min calculated for 0.055 af (100% of inflow) Center-of-Mass det. time= 173.8 min ( 992.4 - 818.6 ) Volume Invert Avail.Storage Storage Description #1A 563.00' 1,082 cf 12.75'W x 85.17'L x 4.00'H Field A 4,343 cf Overall - 1,638 cf Embedded = 2,705 cf x 40.0% Voids #2A 563.50' 1,638 cf Cultec R-360HD x 44 Inside #1 Effective Size= 54.9"W x 36.0"H => 9.99 sf x 3.67'L = 36.6 cf Overall Size= 60.0"W x 36.0"H x 4.17'L with 0.50' Overlap 44 Chambers in 2 Rows Cap Storage= 6.5 cf x 2 x 2 rows = 25.8 cf 2,720 cf Total Available Storage Storage Group A created with Chamber Wizard Device Routing Invert Outlet Devices #1 Discarded 563.00' 0.500 in/hr Exfiltration over Horizontal area below 563.50' Conductivity to Groundwater Elevation = 560.30' #2 Primary 563.65' 2.5" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #3 Primary 564.30' 6.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Primary 564.70' 5.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #5 Primary

0' 6.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Primary 564.70' 5.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #5 Primary 566.95' 4.0' long x 1.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.50 3.00 Coef. (English) 2.69 2.72 2.75 2.85 2.98 3.08 3.20 3.28 3.31 3.30 3.31 3.32 Discarded OutFlow Max=0.02 cfs @ 12.50 hrs HW=564.31' (Free Discharge) 1=Exfiltration ( Controls 0.02 cfs) Primary OutFlow Max=0.12 cfs @ 12.50 hrs HW=564.31' (Free Discharge) 2=Orifice/Grate (Orifice Controls 0.12 cfs @ 3.59 fps) 3=Orifice/Grate (Orifice Controls 0.00 cfs @ 0.32 fps) 4=Orifice/Grate ( Controls 0.00 cfs) 5=Broad-Crested Rectangular Weir ( Controls 0.00 cfs)