Groundwater can be compared to a hidden treasure beneath our feet, permanently exchanging with rivers and lakes. It requires comprehensive protection, as it is the main source of drinking water supply which is however very sensitive to pollution. Once substances have contaminated the groundwater, the degradation process is extremely slow, if at all. In order to maintain the stock of groundwater it must be managed sustainably, which means that, on the long run, groundwater abstraction must not exceed natural recharge due to precipitation.
In spite of unfavourable living conditions, such as darkness, cold and nutrient deficiency, non polluted groundwater may be rich in biological species.
The management plan 2015 proves that there are sufficient groundwater reserves in almost all regions of the Rhine valley and that they are sufficiently recharged. However, there does exist a threat to the quality of certain bodies of groundwater.