Analysis - Proposed Conditions NOAA 24-hr D 10 YR-C Rainfall=5.38"
Prepared by Civil Core Consulting Printed 12/19/2025
HydroCAD® 10.20-8a s/n 13637 © 2025 HydroCAD Software Solutions LLC Page 185
| Inflow Area = | 38,333 sf, | 22.73% Impervious, | Inflow Depth = 1.36" for 10 YR-C event |
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| Inflow = | 0.67 cfs @ | 12.19 hrs, | Volume= 4,330 cf |
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| Outflow = | 0.27 cfs @ | 12.17 hrs, | Volume= 4,330 cf, Atten= 60%, Lag= 0.0 min |
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| Discarded = | 0.27 cfs @ | 12.17 hrs, | Volume= 4,330 cf |
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| Primary = | 0.00 cfs @ | 0.00 hrs, | Volume= 0 cf |
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| Routed to Link 34L : POA 3 |
Routing by Dyn-Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs
Peak Elev= 91.01' @ 12.50 hrs Surf.Area= 1,150 sf Storage= 294 cf
Plug-Flow detention time=3.5 min calculated for 4,330 cf (100% of inflow) Center-of-Mass det. time=3.5 min (875.6 - 872.1)
| Volume | Invert | Avail.Storage | Storage Description |
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| #1 | 90.75' | 4,888 cf | Custom Stage Data (Prismatic) | Listed below (Recalc) |
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| Elevation
(feet) | Surf.Area
(sq-ft) | Inc.Store
(cubic-feet) | Cum.Store
(cubic-feet) |
|---|
| 90.75
95.00 | 1,150
1,150 | 0
4,888 | 0
4,888 |
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| Device | Routing | Invert | Outlet Devices |
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| #1 | Device 3 | 92.75' | 2.5" Vert. Orifice C= 0.600
Limited to weir flow at low heads |
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| #2 | Device 3 | 94.50' | 48.0" x 48.0" Horiz. Grate C= 0.600
Limited to weir flow at low heads |
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| #3 | Primary | 92.75' | 12.0" Round Culvert
L= 7.0' RCP, groove end projecting, Ke= 0.200
Inlet / Outlet Invert= 92.75' / 92.65' S= 0.0143 ' /' Cc= 0.900
n= 0.012 Concrete pipe, finished, Flow Area= 0.79 sf |
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| #4 | Discarded | 90.75' | 10.000 in/hr Exfiltration over Surface area Phase-In= 0.01' |
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| Discarded OutFlow Max=0.27 cfs @ 12.17 hrs HW=90.80' (Free Discharge)
4=Exfiltration (Exfiltration Controls 0.27 cfs) |
| Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=90.75' TW=0.00' (Dynamic Tailwater)
3=Culvert ( Controls 0.00 cfs)
1=Orifice ( Controls 0.00 cfs)
2=Grate ( Controls 0.00 cfs) |
Discarded OutFlow Max=0.27 cfs @ 12.17 hrs HW=90.80' (Free Discharge)
4=Exfiltration (Exfiltration Controls 0.27 cfs)
Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=90.75' TW=0.00' (Dynamic Tailwater)
3=Culvert (Controls 0.00 cfs)
1=Orifice (Controls 0.00 cfs)
2=Grate (Controls 0.00 cfs)
Pond 8P: INFILTRATION BASIN 3
Grate
Civilist
Exfiltration