MICROBIOLOGICAL ASSESSMENT OF THE LAKES BISTARAC AND VIDARA WATER QUALITY

UDK: 574.5:579.68(285)(497.6) In the spring and summer season of 2014, the change in the number of coliform and heterotrophic bacteria in specific localities of lake Bistarac and lake Vidara were observed and analyzed. Lake Bistarac was formed after the cessation of surface mining in the open pit, while lake Vidara is the artificial lake in the area of Gradacac made in order to protect the industrial zone of flooding. Both of these lakes, placed in Tuzla Canton, are very attractive for tourist and frequently are used for swimming, fishing and recreation. Results of this study showed an increased number of coliform bacteria in both periods, and the presence of Escherichia coli as a direct indicator of fecal pollution, while, as an additional indicator of fecal pollution, Citrobacter and Enterobacter were identified. From the total number of analyzed water samples of the lake Bistarac, 60% of samples belonged into to the second class, and 40% into the first class of water quality. Lake Vidara showed poor quality as the 80% of the analysed samples belonged to the second class and only 20% into the first class of water quality. For the microbiological assessment of the water quality standard microbiological procedures and methods were used. One of the main reasons for poor hygienic state of these two lakes is unregulated sewage network of the villages, restaurants and camping areas placed near the lakes. The increased number of fecal bacteria was found in the water of both lakes, which can be highly dangerous for the human population. Since both lakes are used for recreational purposes it is necessary to establish an appropriate monitoring system on the basis of which is possible to take measures and to protect and improve water quality.