Groundwater is a resource of utmost strategic importance for Slovenia and Germany providing drinking water of good quality to its population. For decades, management of this key resource has received the highest priority of our national hydrological services. In the framework of the service activities in both countries, groundwater status in terms of quantity and quality has been observed and studied systematically for more than 50 years. In the eighties of the last century the first models forgroundwater recharge assessment at local and regional scale were developed. However, long time assessment of groundwater status and estimation of groundwater recharge for heterogeneous hydrogeology systems of entire countries were not available. In this respect the GROWA model, developed at the Agrosphere Institute of Research Centre Jülich, was one of the first groundwater recharge models that was applicable at the level of river basins and Federal States in Germany. The transfer and application of the GROWA model to groundwater systems of the Republic of Slovenia was a pioneering effort, establishing for the first time a groundwater recharge model covering the whole territory of Slovenia and not focusing on individual aquifers only, being the practice in Slovenia before. [...
