The modern water supply infrastructure in Bulgaria was created in the 1970s and 1980s and over the last ten years has been gradually improved. There are over 3000 water sources with permanent exploitation for drinking water supply in the country. According to the Ministry of Health, about forty-percent of the water used for drinking comes from surface water sources. Public health authorities must improve preventive actions such as disseminating health information, controlling the drinking water disinfection, regulating the treatment and preparation of foods, and promoting prevention strategies among vulnerable population groups. There is no doubt that deteriorated hygienic conditions caused by lack of tap water help the dissemination of gastro-intestinal infections, creating sporadic morbidity over the years. The prolonged dry period had an adverse effect on the capacity of water sources in Bulgaria. Karst springs, as well as drainage that captures rain water are the most vulnerable and rapidly affected by drought.