A dam or barrier built across a tidal channel to allow a power-generating plant to operate. The siting of the barrage requires there to be a tidal range in excess of 5 m and a large water body open to the sea, with a narrow entrance. One barrage and generating plant in operation since 1960 is on the Rance estuary in Brittany, France. It generates electricity by the use of two-way turbines, as water flows in and out of the estuary through the barrage. The Severn estuary and Morecambe Bay are potential sites for tidal barrages in the British Isles.
Subjects: Ecology and Conservation — Earth Sciences and Geography.