Evaluating the Form of the Rational Equation
Publication: Journal of Hydrologic Engineering
Volume 19, Issue 1
Abstract
The Rational method is widely used in the design of hydraulic structures, such as storm sewers and culverts. Many engineers consider the Rational equation a rule-of-thumb method and dismiss it in favor of regional flood-frequency equations. This paper presents a regional flood-frequency analysis of 72 gaged watersheds in Kansas, ranging in size from . The analysis results in regression equations for the 2-year to 100-year peak discharges that are statistically indistinguishable from the Rational equation. The resulting Rational equations explain more of the variance in flood quantiles than the standard form of the USGS regional flood-frequency equations that are used in Kansas.
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Acknowledgments
The research reported in this paper was funded by the Kansas DOT under K-TRAN grant KU-06-4. This support is gratefully acknowledged. The writers thank two anonymous reviewers and an associate editor who made several insightful recommendations for improving the manuscript.
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Information & Authors
Information
Published In
Journal of Hydrologic Engineering
Volume 19 • Issue 1 • January 2014
Pages: 265 - 269
Copyright
© 2014 American Society of Civil Engineers.
History
Received: Jun 25, 2009
Accepted: Dec 13, 2012
Published online: Dec 15, 2012
Discussion open until: May 15, 2013
Published in print: Jan 1, 2014
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