NRCS DIMENSIONLESS UNIT HYDROGRAPH

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NRCS DIMENSIONLESS UNIT HYDROGRAPH
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NRCS DIMENSIONLESS UNIT HYDROGRAPH
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PEAK FLOW
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Timing Considerations

• Lag Equation (Regression)
• Segmental Method (Physically Based)

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Lag Equation
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Segmental Method

• Sheet Flow Overland Flow
• Shallow Concentrated Flow (Rills and Gullies
• Open Channel or Pipe Flow (Conveyance System

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Sheet Flow
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Sheet Flow
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Sheet Flow
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Shallow Concentrated Flow
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Shallow Concentrated Flow
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Open Channel Flow
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Open Channel Flow
Topen channel flow Length/Velocity
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Time of Travel
Tt t1 t2 t3
Sheet Flow Shallow Concentrated Flow Open Channel
or Pipe Flow