Issue |
La Houille Blanche
Number 8, Décembre 2001
|
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Page(s) | 72 - 78 | |
DOI | https://doi.org/10.1051/lhb/2001094 | |
Published online | 01 July 2009 |
Causes et conséquences du blocage actuel de la dynamique fluviale et du transit sédimentaire du Rhône
Reasons and consequences of the actual reduction of Rhône river sediment transport
1
Hydratec, Conseiller technique de Territoire Rhône, Etablissement Public Territorial du Bassin du Rhône
2
Sogreah
Abstract
The bed load brought from the global watershed to the Rhône river has been reduced since 1950 from about 1Mm3/year to 0.2 Mm3/year. Gravel extractions, hydropower and improvements works on watershed are the principal reasons of it. The suspended load is more significant but has been divided by two since 1950. In the same time, power stations built in Rhône river by CNR (Compagnie Nationale du Rhône), have considerably reduced it solid flow capacity. In consequence, Rhône river, which was once very mobile, is now a quiet river. A.ffluents do not bring any more sand and gravel, and the bed load of Rhone river can not be moved because of the insufficient slopes in the reservoirs and the discharge reductions in bypassed sections. Principal impacts are sitting and vegetation development of the bed. It requires specific actions to maintain a bed close to a natural state.
© Société Hydrotechnique de France, 2001