TREASURES FROM OUR ARCHIVES: THE NAVIGATION STRUCTURES OF THE DONZERE-MONDRAGON WATERFALL ON THE RHONE

摘要

Toward the end of the Second World War, as early as July 1944, the French government asked Compagnle Nationale du Rhône (CNR) to cany out a hydroelectric development project on the Rhône River to provide the power needed for the country's reconstruction. This project would be party financed by the Marshall Plan. The Donzère-Mondragon scheme is located on the Lower Rhône between Valence and Avignon, between the confluences of the Isère and Ardèche rivers. There Is what Is called the "robinet de Donzère " (Donzère tap), one of the finest water heads on this river, 0.8 m per km. It was constructed between 1948 and 1952. The hydropower dam, at Bollène in the Vaucluse region, is called the André Blondel dam. With a remarkable architecture due to the architect Théodore Sardnal, it was listed as an historical monument in 1992. The diversion channel is 28km long: 17 km of headrace channel and 11 km of outlet channel. The dam exploits a water head of 22.50 m. lt is equipped with six adjustable-blade Kaplan turbines, developing 354 MW and producing 2 billion kWh per year. The lock, 26 m high, was the highest in the world at fiat time. The channel is crossed by nine large bridges, some of which are remarkable. The hydraulic structure has a threefold role of power production, navigation and irrigation, illustrating the three missions of the CNR. The project was gigantic, employing up to 7,000 men fora period of five years. They morked 54 hours a week. Living facilities were built, which became real cities. Dutch dredgers dug the channel. American machines such as dumpers, scrapers and bulldozers worked on the project. At the time it was called the biggest project, the largest lock, the most productive power station in Europe, and even the "French Suez"!