Numerous karst springs are important resources of local drinking water supply,covering almost half of the countryćs needs. This paper discusses water supply in the past and today, problems and challenges that it is facing. The quality of karst water sources is good, however, the presented researches show that the protection of catchment areas has so far been insufficient. Due to uneconomical use, the available quantities of water resources are also threatened. To keep our biggest reservoir of qualitative drinking water safe, further planning of water supply will need to base on appropriate research, as are the presented ones.