Microorganisms are the ideal indicators of the organic pollution of the surface waters because of their ability to promptly respond to environmental changes. Due to poor economic situation and lack of law implementation, most wastewaters in Serbia are released directly into a surface water recipient without any or a limited treatment. This practice has created numerous highly polluted surface waters in the region. Therefore, we conducted seasonal monitoring of the bacteriological quality of the Nišava River located in the southeastern Serbia in order to assess the extent of its organic and faecal pollution. A total number of heterotrophs, Escherichia coli and intestinal enterococci counts were determined by standard cultivation methods in samples from five locations along river. In most instances, bacteriological quality of Nišava water belonged to the classes of low or moderate organic and faecal pollution. The samples taken downstream of the city of Niš were the most polluted. Intestinal enterococci and E. coli counts indicated a moderate faecal contamination. Since bacterial counts can reveal a presence of faecal pollution and therefore presence of potentially pathogenic bacteria, a proper microbiological monitoring of surface waters used as a source of drinking water, like the Nišava River itself is critically important.
- Escherichia coli
- intestinal enterococci
- microbiological indicators
- surface water quality
- First received 15 September 2015.
- Accepted in revised form 17 May 2016.
- © IWA Publishing 2016