Are fuse weirs so fusible ?

Abstract

Discharge weirs are essential safety elements to avoid breaches by overtopping of the dykes, in case of a flood exceeding the reference event. Building an earth fill fuse over the weir is a tempting solution to increase the hydraulic efficiency of a spillway while limiting its length. Then the question is: will the fuse behave as expected ? This paper proposes a discussion about this kind of fuse equipment, based on the assessment of an old works and on the observation of two more recent during the December 2003 flood. Alternative solutions are described.