This fusegate device based on the same triggering principles as the Classical Fusegate is not dragged by the flood but rather it disappears downwards like a valve. It can be set back in place manually by the operator after the flood has passed.
A recoverable fusegate
An inclined and mobile panel is supported by a set of hinged arms. It allows moderate floods to be discharged over its crest. A negative pressure chamber is mounted in the base of each module. It is equipped with drainage purges at the interface with the threshold.
The storage level of the retention is raised to the level of the panel discharge crest. When the reservoir is full, the flood flows over the crest of the folding fusegate, which acts as a free threshold (Fig. 1).
When, during major floods, the upstream water level reaches the crest of the supply well (in an annex structure), the negative pressure chamber is supplied (Fig. 2).
The negative pressure force generated in this chamber actuates the tilting mechanism of the folding fusegate. The panel folds in order to discharge the flood (Fig. 3).
The tilting rate of each panel is precisely adjusted by the admission well height setting. After a major flood has passed, the panel set back into its original configuration.