ABSTRACT
The concept of peak flow reduction through lateral diversion weir structures is increasingly targeted for flood control management at rivers. A part of the discharge is thereby diverted into retention basins or flood plains, preventing the capacity to be exceeded in the downstream river reach. Thus, dyke overtopping at unforeseen locations is avoided, particularly for events surpassing the design flood. There are different types of overflow or intake structures, which may be fixed-crested or erodible if overtopped (fuse plug embankments), equipped with tilting or overturning fuse gates as well as with movable gates. Each has its pros and cons regarding hydraulic behaviour, operational safety, maintenance, and cost. In this study, different types of lateral diversion weir concepts are presented and discussed with a special focus on typical Swiss river conditions. Furthermore, the hydraulic characteristics are highlighted and examples regarding lateral flood discharge at various Swiss location are given.
