Of the various empirical formulae relating the flood peak to the catchment area,
For an annual flood series arranged in decreasing order of magnitude, the return period for a magnitude listed at position m in a total of N entries is
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The probability that a hundred year flood may not occur at all during the 50 year life of the project is
The general equation for hydrological frequency analysis states that x_{T} = value of a variate with a return period of T years is given by x_{T} =
For a return period of 100 years the Gumbel’s reduced variate y_{T} is
An annual flood series contains 100 years of flood data. For a return period of 200 years the Gumbel’s reduced variate is
To use Gumbel’s method to estimate the magnitude of a flood with a return period of T years, the following data pertaining to annual flood series are sufficient
To estimate the flood magnitude with a return period T by the logPearson Type III method, the following data pertaining to annual flood series are sufficient
To estimate the flood magnitude with a return period of T years by using lognormal distribution, the following statistics of data are absolutely necessary
The recurrence interval of an event is T_{A} in annual series and T_{p} in partialduration series, then
31 docs280 tests

31 docs280 tests
