Drinking water must be virus-free. However, it has been observed and demonstrated that various pathogenic viruses are capable of transmission through water and that such viral diseases may have far-reaching health and socio-economic implications. Over a four-year period 135 drinking water samples were collected in a middle-sized town in Croatia. The percentages of positive findings varied from 0 to 10%, the average being 3.7%. These results are compared with the ones given by similar studies in different parts of the world.