Question

Problem 15. The 24-year historical data (annual maximum series) collected from a nearby station at a river was used
to develop the statistical parameters that will be used in the hydrologic-hydraulic study for the design of a new
bridge. The expected project life of the bridge is 50 years. The hydraulic and bridge conditions requires to use the
500 year flood (based on annual maximum data series) for design purposes. The bridge construct will require three
years and the insurance company requires to build temporary structures to prevent damages from the 25 year flood
condition. Determine:
(a) Probability assigned to the flood with 500-yr recurrence.
(b) The probability of not observing the 500-yr recurrence flood at a given year.
(c) Risk probability that this 500-year return period flood will be exceeded at least once in the 50-year project life.

(d) Risk probability that the 25-year return period flood will be exceeded at least once in the 3-year construction
period of that project.

Answer 1