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    Bransby Williams Method

    Parameters

    Flowpath Length - The length of the Sheet flow path.

    Land Slope - The slope of the hydraulic grade line.

    Area - The catchment area.

    Calculation

    where:

    L  = Length of overland flow (Km)

    A = Area (Km2)

    S = Average catchment slope (%)

    tc = time of concentration (hrs)

    Parent topic: Time Of Concentration Calculator

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