Riverbank filtration has been used along the Rhine River for many decades. Iron, phosphates, and heavy metals are eliminated by precipitation without causing aquifer clogging. Overall, organics are effectively removed by as much as 75 percent via biological oxidation whereby nitrate serves as an electron acceptor under anoxic conditions. Halogenated organics with low biodegradability penetrate more easily. Improvements in river quality influence both the bank filtrate and the finished water. Specific trace organics are poorly removed when their halogen content is relatively high. Bank filtration has proved to be a valuable treatment step, and in combination with activated carbon filters ensures a safe drinking water. Includes 8 references, tables, figures.