Hydropower
The flow of the Rhine offers the possibility to produce energy without write pollutants into the environment and without the water consuming. Hydroelectric power station, however, convert the turbines the enormous power of dammed water in power, acting in many ways detrimental to the ecological function and passability of watercourses.
The strong river development in the upper reaches of the Rhine, where numerous reservoirs and dams were built, and the construction of 21 dams between Lake outlet and Iffezheim, affecting among others the migration of fish and can cause significant mortality in fish when injured in their downstream migration through the turbines (cf.. ICPR Technical report no. 140 for the Rhine tributaries). Through the accumulation of water and thus caused loss of habitats, especially in relation to the employed in smaller waters in particular in the Alps hydropeaking of power plants, the natural water development is damaged.
Moreover barrages perform below the weirs to bed erosion on free-flowing route, so that the flow also decreases the level of groundwater, with negative consequences for the pastures, but also for drinking and agriculture. This fact is for example counteracted below the Iffezheim barrage by regular addition of sediment under water.