In order to reduce the risk of flooding upstream of the town of Montbéliard (France), a retention basin was created.

The surrounding dikes of this basin were previously protected from overtopping by a fuseplug that was designed to be activated for exceptional floods.

A diagnostic study performed in 2004 highlighted the unreliable hydraulic operation of the structure and the inadequate safety of the system as a whole.

Accordingly, the existing fuseplug had to be replaced by a more reliable control system.

Following a detailed study in 2007 taking into account all the technical and economical aspects, including alternatives such as fuseplug, free sill, mechanical valves, etc., the decision was made to construct a 56 m-long protective spillway equipped with fusegates, and to reconstruct the dikes of the retention basin.