Microbiological quality and the Sava River – the whole river survey

Abstract

Object of the research: Knowledge of the extent of faecal pollution of the Sava River is extremely important as many of the large settlements situated on the river bands discharge high quantities of untreated or improperly treated wastewaters directly into river.

Materials and methods: The level of faecal pollution was assessed in September 2014 at 9 sites along the Sava River: Radovljica, Litija, Čatež (SLO), Zagreb, Jasenovac, Slavonski Brod, Županja (HR), Sremska Mirovica and Belgrade (RS). The numbers of coliforms and enterococci were assessed by the most probable number technique (Colilert/Enterolert Quanti-Tray 2000 system) while the quantification of Clostriduim perfringens was performed by membrane filtration (ISO 14189:2013).

Results: The numbers of coliforms indicated critical level of pollution in almost all samples while the numbers of enterococci indicated moderate to critical pollution. The highest level of pollution assessed by Escherichia coli, enterococci and C. perfringens was detected at the site Litija.

Conclusions: Our results indicated presence of faecal pollution along the Sava River. At the majority of investigated sites critical pollution was recorded indicating unsatisfactory level of water quality. With exception of the site Litija, the hotspots of faecal pollution could not be identified.