The evaluation of the bacteriological examinations relates on 2330 water-samples, which were taken from 76 bathing-places of 23 Carinthian lakes in the course of 11 years. The examinations were performed for the purpose of hygienic control. After a short supervision on the methods of examination and of sampling the base of judgement is discussed. A relation to the limnological classification of the lakes could be made from the hygienic point of view. In bathing lakes in the alpine region the experiences proved a lower border-value for the indicators of fecal-charge more from the reason of lake-protection than from the reason of protection of the human health. A proposal for the judgement of bathing-water from lakes is made, including the significance of enterococci, and a scheme for recording the results is given.