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Methods for determining manning's coefficients for Illinois streams

D.T. Soong·T.M. Halfar·M.A. Jupin·L.A. Wobig
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Abstract

Determination of Manning's coefficient, n, for natural streams remains a challenge in practices. One source for determining the n-values that has received practitioners' attention is presenting the n-values determined from field data (measured discharge and water-surface slope) in combination of photographs and site descriptions (ancillary information). Further improvements in the visual approach can be made in presenting site characteristics and describing site ancillary information. In this manner, users can use the presented information for sites of interest with similar features. This approach in a current project on the subject for Illinois streams is discussed.

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D.T. Soong, T.M. Halfar, M.A. Jupin, L.A. Wobig. 2004. Methods for determining manning's coefficients for Illinois streams. https://pubs.usgs.gov/publication/70026321

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