Via groundwater and surface waters all fields, meadows and vineyards drain into the Rhine. Excessively intensive and inappropriate agriculture may pollute waters and their biocoenosis in many ways, in particular due to inputs of nutrients and pesticides.
It is difficult to control diffuse nutrient and pollutant inputs. Nutrient excesses arise from excessive use of fertilizers which may e.g. be applied at other times than during growth periods, meaning that they are not or only to a very small extent absorbed by plants. The rest percolates into groundwater or is washed off at the surface. From the point of view of water protection, farming with row cropping of vegetables such as corn, sugar been and wine which hardly cover the soil is particularly critical.
Apart from other water protection measures, agriculture near to nature with a stronger ecological orientation is a good alternative. It serves the objectives of water and nature protection if closed substance circuits are used, stock density is adapted to the size of the surface and fertilization takes into account plant requirements.
In 2007, the Ministers in charge of the Rhine again demanded to further reduce discharges of pollutants and nutrients, above all of diffuse origin, such as agriculture in order to limit hazards for human health, the ecosystem or its uses.