Donzère-Mondragon Dam, Hydroelectric power station in Bollène, France

The Donzère-Mondragon Dam is a major hydroelectric installation with an integral navigation lock situated on the Rhône River. The structure combines power generation with river transportation in a single facility that spans a considerable length along the river.

Built between 1948 and 1952 on the Donzère-Mondragon canal, the dam was designed by architect Théodose Sardnal and inaugurated on 25 October 1952 by President Vincent Auriol. It was listed as a monument historique on 4 June 1992.

The installation is also called barrage André-Blondel, after the engineer André Blondel. Its Bollène lock, on the right bank, has a drop of 23 metres between downstream and upstream levels, the greatest in France. A fish pass beside the dam lets Rhône fauna move both ways.

The structure sits on the Donzère-Mondragon canal at Bollène, not on the Rhône itself, and is viewed from outside only. The Bollène lock on the right bank has a 23-metre drop between upstream and downstream, the largest in France, so boats take time to pass. A fish pass runs along one side of the dam.

The lock is not merely a dam structure but an active traffic artery where cargo boats and private vessels pass through daily. This makes it one of the few places where you can see modern industrial engineering directly linked with living river use.