The Rhône is the great river of the southeast. Rising in the Alps, it passes through Lake Geneva (French: Lac Léman) to enter France, which has 324 miles of its total length of 505 miles. At Lyon it receives its major tributary, the Saône. In eastern France the direction of the main rivers is predominantly north-south through the Alpine furrow. The regime of the Rhône is complex. Near Lyon the Rhône and its important Isère and Drôme tributaries, draining from the Alps, have a marked late spring-early summer peak caused by the melting of snow and ice. While this peak is generally characteristic of the river as a whole, it is considerably modified by the contribution of the Saône, of the Durance, and of some tributaries in the Mediterranean south as a result of the fall-winter rainfall peak. Thus the powerful Rhône has a remarkably ample flow in all seasons. The course of the river and the local water tables has been much modified by a series of dams to generate power and to permit navigation to Lyon. The Rhône also supplies cooling water to a series of atomic power stations. West of the Rhône, the Bas Rhône-Languedoc canal, constructed after World War II to provide irrigation, has proved to be an essential element in the remarkable urban and industrial development of Languedoc. East of the Rhône the Canal de Provence taps the unpolluted waters of a Rhône tributary, the Durance, supplying Aix-en-Provence, Marseille, Toulon, and the coast of Provence with drinking water and providing impetus for urban expansion. At its delta, beginning about 25 miles from the Mediterranean, the Rhône and its channels deposit significant amounts of alluvium to form the Camargue region.…
