Along the Rhine, flood control is a permanent issue of concern. Here, too, the ecological targets of the Water Framework Directive give new perspectives. Ecological diversity increases where rivers are re-natured, dead river branches are reconnected and alluvial areas are re-established as floodplains. At the same time, natural flood retention areas are formed. Preventive flood protection is modelled on natural river landscapes: The flood waves of rivers with enough space to break the banks are less high.