The results of microbiological analyses of raw water of two water supplies of city of Novi Sad (Ratno Ostrvo and Petrovaradinska Ada) are presented. The sampling was performed monthly during 2008 and 2009. The following parameters were monitored: aerobic mesophilic bacteria count at 37 deg C, organotroph count (water categorization according to Kohl), facultative oligotrophs, lipolitic and hydrocarbon-oxidizing bacteria count. The count of organotrophic bacteria was determined using low nutritive R2A medium. In addition, water was classified according to enzymatic activity of water, expressed as index of phosphatase activity (IFA).

The paper presents aquatic macroinvertebrate community at four investigated localities of the Gradac river. Sampling was carried out during 2003 and 2006. Community structure and composition, together with field data, were used to estimate the water quality status of the river. A total of 87 taxa have been recorded. Insects were found to be the most diverse component, especially Ephemeroptera. Insects were dominant in the regard of the quantitative structure of the community, as well. Recorded community indicates good water quality, ranged between oligosaprobic and beta-mesosaprobic status (1st-2nd class according national classification scheme).

The paper presents the results of aquatic macroinvertebrates community analyses of the Milesevka river (Lim river watershed; Sava river basin) with aim to evaluate saprobiological status. Sampling was carried out on five localities during 2005. A diverse community (62 taxa) has been recorded during the investigation. Results of saprobiological investigation indicate satisfactory water quality, which is, according to national legislative, within 1st and 2nd quality class.

During the summer 2009 physical, chemical, biochemical and bacteriological analyses of water of rivers Mušnica and Suški Potok were performed. Microbiological analysis point out that waters belong to the 2nd class by Kohl. The river Mušnica had slightly polluted water, and river Suški Potok had very slightly polluted water. According to the Regulation on Classification of Surface Waters in Republic of Srpska (Bosnia and Herzegivina) all the observed parameters belong to the first or second water quality class. Only the stream Suški Potok has chloride concentration that exceeds a third-class quality. On the basis of observed characteritics it can be concluded that Mušnica and Suški Potok have a satisfactory water quality.

This paper presents the results of assessment of dredging activities at the Romanian side of the channel on the quality of water and sediment in the Begej channel (in Serbia). Sediment monitoring results have pointed to the increasing content of metals in surface sediments, as well as increased concentrations of some metals (Cd, Ni and Cr) compared to the period from 2008. Results of the water quality after the dredging at the Romanian side shows low metal concentrations, which is probably caused by coprecipitation of metal in the iron in forms of amorphous and hydrated oxide. Monitoring of water and sediment should be conducted continously through the year in order to follow the trend of sediment and water quality and targeted when we know the exact time of some of the activities in the channel.

The city of Novi Sad uses groundwater as drinking water source. For this purpose only water from Danube alluvium is used, and the water is abstracted at three sites. The Danube water and sediment quality in the zone of the drinking water sources is of great importance, as the river Danube recharge alluvial aquifer. The microbiological quality of these environments was monitored, in order to determine their influence on drinking water quality. The water characterization was carried out using sanitary and ecological microbiological parameters of Danube water and sediment.