Assessment of the water quality in the Moraca River basin (Montenegro) using water quality index

In this paper, the water quality of the Moraca River and its main tributaries (the Zeta and the Cijevna) were analyzed, using the Water Quality Index (WQI) methods. Data from 12 hydrological stations (HS) from 2010 to 2018 were used. The analysis included ten parameters of physic, chemical and microbiological water quality: oxygen saturation, BOD5, ammonium ion, pH value, total nitrogen oxides, orthophosphates, suspended solids, temperature, electrical conductivity and coliform bacteria. Calculations for all 12 HS were made using the Serbian Water Quality Index (SWQI). The results of the research showed that the general situation is not discouraging, because the SWQI values ranged from 73-97, which according to the categorization of water quality corresponds to the classes good, very good and excellent. The only exceptions were the two measuring stations in the lower course of the Moraca River (City Collector and Grbaci). During the entire observed period, the water quality was the worst on the profile of the City Collector (SWQI between 39 and 71) on Moraca River. Also, downstream on Moraca River, on HS Grbavci for 2015, the average annual value of SWQI was 70, which according to the gradation corresponds to the class of poor quality. The biggest sources of pollution were municipal wastewaters, followed by agricultural activities and illegal garbage disposal both along the stream and in the river itself. It follows that the lower part of the Moraca River was the most polluted in the observed basin. This is a serious problem, especially since it is a part of the Moraca River that flows through the most populated and most agriculturally active parts of Montenegro (Podgorica, Zeta Plain, Ljeskopolje). Therefore, it is necessary to take adequate measures as soon as possible, which primarily relate to the introduction of wastewater treatment technology and to educate population about the importance of river water conservation.