Evaluation of design flood frequency methods for Iowa streams
By: investigators A.A. Bradley, Jr., L.L. Wehmeyer and L.C. Chen
Contributors: Chen, Lijing; Wehmeyer, L.L. (Loren L.); Iowa. Highway Research Board; Iowa. Department of Transportation
Publisher: IIHR-Hydroscience & Engineering, College of Engineering, University of Iowa
Published: 2009
Place of publication: Iowa City, Iowa
Language: eng
Number of pages: 94
Subjects: Runoff; Floods; Flood forecasting; Rational formula (Hydraulics); Mathematical models
Description: The objective of this project was to assess the predictive accuracy of flood frequency estimation for small Iowa streams based on the Rational Method, the NRCS curve number approach, and the Iowa Runoff Chart.  The evaluation was based on comparisons of flood frequency estimates at sites with sufficiently long streamgage records in the Midwest, and selected urban sites throughout the United States.  The predictive accuracy and systematic biases (under- or over-estimation) of the approaches was evaluated based on forty-six Midwest sites and twenty-one urban sites.  The sensitivity of several watershed characteristics such as soil properties, slope, and land use classification was also explored.  Recommendations on needed changes or refinements for applications to Iowa Streams are made.
Notes: "June 2009."

"IHRB Project TR-533."

Includes bibliographical references (p. 91-94).

Final report.

Also available via the Internet.

Sponsored by the Iowa Highway Research Board and the Iowa Dept. of Transportation IHRB project TR-533.