Mapping the Groundwater Vulnerability in North Rhine–Westphalia,Germany

Abstract

Within the framework of a hydrogeological mapping project, an information system evaluating the groundwater vulnerability in North Rhine-Westphalia has been under development since the year 2000. The parametrical evaluation system used, according to (Hölting et al., 1995) is based on five input parameters: the thickness of the groundwater overburden, the soils available water capacity, the lithology of the deeper underground, the amount of seepage water as well as the hydrogeological conditions regarding perched or artesian groundwater surfaces. The requisite parameters are available throughout Germany as spatial data. The system is applicable in both soft and hard rocks. It classifies the groundwater overburden in five different sections from surfaces having very low risk of groundwater pollution up to areas with very high risk of contamination. The classification characterizes the expected dwell time of pollutants in the vadose zone. Up to now, all potential pollutants have been treated without considering their differing transport and degradation processes. Our current research includes attempts to improve this situation.