Submitted to: Journal of Irrigation and Drainage Engineering
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/28/2014
Publication Date: 2/1/2015
Citation: Hunt, S.L., Kadavy, K.C. 2015. Discussion of "Aeration, flow instabilities, and residual energy on pooled stepped spillways of embankment dams" by Stephen Felder and Hubert Chanson. Journal of Irrigation and Drainage Engineering. 141(2):07014038-1-3.
Interpretive Summary: Flat-stepped and pooled stepped spillways offer design alternatives for engineers tasked with upgrading aging dams. Researchers in Austrialia conducted a model study to examine the differences between flat-stepped and pooled stepped spillways. Recommendations are provided to the researchers with regards to the experimental set-up, and insight was given to developed equations provided by the researchers. Additionally, questions were raised with respect to data presented regarding design paramters for stepped spillways.
Technical Abstract: Stepped spillways applied to embankment dams provide overtopping protection and address a common deficiency in aging dams by providing increased spillway capacity. Pooled-stepped spillways offer a design alternative to the traditional flat-stepped spillways. Researchers from the University of Queensland in Austrailia conducted a model study to examine the differences between the flat-stepped and the pooled stepped spillways. Flow characteristics between flat-stepped and pooled stepped spillways have similarities but also differences. The researchers provide relationships for determining inception point, air concentrations, velocities, and residual energy. This manuscript provides recommendations to the researchers with regards to the experimental set-up, and additional insight to the inception point relationships provided by the authors. This manuscript also seeks explanations to the interpretation of data with regards to dimensionless distribution of interfacial velocity.