53:078 Principles of Hydrology (Spring 2004)
Problem #25
Risk and Design Life for a Levee Project
You are called in a legal case involving a flood levee
you designed. Based on the design specifications (mandated by the owners), the
levee protects against the 30-year flood. Still, six years after it was
built, the levee was overtopped. The owners think they were ripped-off. The
judge (and jury) want to know the following:
- What is the probability that the levee will fail in any given year?
- What is the probability that the levee will not fail in six years?
- What is the probability that the levee will fail in six years?
- What would you (the engineer) consider to be the design life
(in years) of the levee as constructed? The judge and the owners agree that
the risk of failure (at least one overtopping) should be no more than 1 in 4
(0.25) during its design life?
- What design return period would you have selected for the levee if the
allowable risk of failure during the 30-year design life is 1 in 4 (0.25)?
Last changed on
04/05/04
by aab.