Located in the Aube near Troyes, the lake-reservoir of the Orient, called Seine, was commissioned in 1966 and was erected as a diversion of the Seine to stop the floods of the river and support its flow. It is a lake closed by five dams. The effects of the filling and emptying cycles and the action of the waves have caused many degradations (cracks, cavities ...) on the asphalt coating of the various dams, to the point of jeopardizing the maintenance and safety of the structure. Upstream riprap works will stabilize, strengthen and secure the 3 main dikes, La Morge, Beaumont and Chavaudon, in order to guarantee protection against flooding due to the floods of the Seine of the Trojan agglomeration and those located further downstream including the Parisian agglomeration.