A hydraulic structure has an expected life of 25 years and is designed for a flood magnitude of return period 50 years. The risk of failure of the structure during its life is

From the past rainfall records at a place, it was observed obtained that a maximum rainfall depth of 200 mm in 12-h has a return period of 50 years. The probability of a 12- h rainfall equal to or greater than 200 mm occurring at the same place at least once in 30 years is _____________ %.

The probability of occurrence of a flood equal to or greater than 20 years flood exactly once during the next 20 years is ____________.

In the Muskingum method of channel routing, the routing equation is written as Q2 = C0I2 + C1I1 + C2Q1. If the coefficients are K = 12 h and x = 0.15 and the time step for routing Δt = 4h, then the coefficient C0 is____________.

If a bridge is designed for a 50 year flood, then the probability that only one flood of the design capacity or higher will occur in the 75 years life of the bridge is _____________.

An annual flood series contains 100 years of flood data. For a return period of 200 years the Gumbel’s reduced variate can be taken as ___________.

A 1 hour rainfall of 10 cm has return period of 50 year. The probability of occurence of 1 hour of rainfall 10 cm or more will occur in each of two successive year is