Meile, TobiasBoillat, Jean-LouisSchleiss, Anton2013-04-092013-04-092013-04-09201310.1080/00221686.2012.738876https://infoscience.epfl.ch/handle/20.500.14299/91399WOS:000317911300008elements. In addition to a prismatic reference channel, 41 different configurations of rectangular bank cavities have been investigated. The purpose was to study the effect of large-scale bank roughness on steady and unsteady flows. The macro-roughness of the channel banks increases the flow resistance. Consequently, the absolute celerity of the surge wave front is also reduced by between 5 and 25%. Based on the concept of an effective channel width for the computation of the mean flow velocity, the relative celerity of the surge wave can be predicted for macro-rough channel configurations. The attenuation of the wave front height is increased by the macro-rough flow resistance as well as by the partial reflections of the surge waves in the cavities and passive retention of the latter.Flow resistancehydraulic modelmacro-roughnesssurge wave experimentunsteady channel flowtext::journal::journal article::research article