Assessment of Groundwater Vulnerability in Croatian Karstic Aquifer in Jadro and Žrnovnica Springs Catchment Area

The groundwater vulnerability assessment is based on the evaluation of physical, chemical, and biological properties of the environment which can provide a certain degree of protection to the groundwater from contamination. In this paper are presented results of application four different methods (SINTACS, EPIK, PI, and COP) for groundwater vulnerability assessment in karstic aquifer in Croatia. The main objectives of the study were to apply the methods on test site where, so far, groundwater vulnerability was never assessed, then to modify the methods in order to improve adaptation to the research field and available data. After comparing vulnerability maps obtained by all four presented methods, it was determined that the most appropriate method is COP + K, which was additionally modified. Although presented methodology is not new, it can be used as a background for land-use planning, because it identifies parts of the catchment area that are, due to its natural features, more vulnerable to human impact. It can be also applied as an additional tool in groundwater protection for delineation of protection zones, and provides very useful data in various fields of water management, especially for karst area in Croatia.