Bed degradation is the dominant morphological process along the freely flowing river Rhine between Iffezheim and the German-Dutch border with degradation rates varying between 5 and 50 mm year1. As a continuing bed degradation may cause severe economical and ecological damage, nature, causes and extent of degradation have been studied using two diving bell watercraft. Additional petrographic examinations of bed sediments as well as bed load measurements have revealed that bed degradation of the Lower Rhine is mainly caused by bed load deficits due to the specific morphotectonic conditions as well as anthropogenic interference, especially impounding of the big tributaries. Low degradation rates are a precondition for certain rehabilitation measures as, e.g. restoring of flood plain areas and reactivation of abandoned channels and meander belts. Therefore stabilisation of the river bed is an important task for ecological river engineering. For the river Rhine a stabilisation strategy is suggested combining conventional river training works, maintenance measures and artificial bed load supply.