Water retention structure represented by a point

This layer describes the structures of all importance preventing the flow of a watercourse, whether in the minor bed (spits, thresholds) or in the major bed (dams) as well as the structures located outside the bed of a watercourse allowing water storage (collinear retention). A similar layer N_OUVRAGE_RETENUE_L describes the works linearly. By agreement, works falling under headings 3110 1° and 2(a) and headings 3250 1° and 3° of Decree 2006-881 of 17 July 2006 are classified as works of interest to public security. Major bed embankments are processed in the N_REDUCTION_LIT_MAJEUR layer, flood protection dykes and canal and river dikes are described in the N_DIGUE_P and N_DIGUE_L layers