A stormwater management system is being designed for a life of 20 years, and a (design) runoff event is to be selected such that there is only 5% chance that the system capacity will be exceeded (i.e., failure) during the design life. (1). Determine the return period of the design runoff event. (2). If the runoff event can be described by a log-normal distribution with a mean of 100 (cfs) and a standard deviation of 75 (cfs), what is the magnitude of the design runoff event (Q in cfs)?

A stormwater management system is being designed for a life of 20 years, and a (design) runoff event is to be selected such that there is only 5% chance that the system capacity will be exceeded (i.e., failure) during the design life. (1). Determine the return period of the design runoff event. (2). If the runoff event can be described by a log-normal distribution with a mean of 100 (cfs) and a standard deviation of 75 (cfs), what is the magnitude of the design runoff event (Q in cfs)?

Traffic and Highway Engineering

5th Edition

ISBN:9781305156241

Author:Garber, Nicholas J.

Publisher:Garber, Nicholas J.

Chapter16: Highway Drainage

Section: Chapter Questions

Problem 9P

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