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Calculate the Design Flood Hydrograph for a Watershed and an SCS Design Storm:
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*Referencing Part 630, Hydrology, Chapter 16, Hydrographs, National Engineering Handbook, USDA, NRCS this calculation is to be used to calculate the flood hydrograph for a watershed using an SCS design storm. For local SCS storms greater than 24 hours and up to 96 hours. |
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Calculation: |
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Designer/Checker: |
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Input: |
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Enter the time of concentration (tc - hr) |
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Enter the gamma equation shape factor (m) |
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Select the SCS Synthetic Design Storm: |
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Rainfall (P - in or mm) |
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Enter SCS curve number (CN) for the drainage area |
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Drainage area (Am - sq mi or sq km) |
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Output: |
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Time to peak, tp = |
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Unit peak discharge, qp = |
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Sum of dimensionless DUH coordinates = |
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Nondimensional time interval of DUH = |
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Peak rate factor, PRF = |
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Volume under hydrograph = |
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Runoff Volume, Vr = |
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