Advanced Methods for the Selection of Urban Runoff Design Storms

Abstract

Urban runoff design storm selection has in the past been arbitrary at times. This has led to inadequate and unreliable capacity design of urban runoff structures. By utilizing a continuous urban runoff digital computer model, the frequency response of selected urban basins to a selected historical point rainfall record is generated. This frequency response is subsequently used as a criterion for the selection of a set of design storms. Expectation and optimization are applied to obtain reliable design storms. Results indicate that both expectation and optimization analysis yield reliable design storms. Application of expectation analysis to a two-parameter design storm model is one practical recommendation of the study.