Study of Chemical, Physical and Microbial Quality of Gargar River, sw, Iran, Using NSF Water Quality Index

Applying water quality indices is one of the monitoring techniques of river water quality. High loads of sampling data, resulted from water quality measurements, are converted to a single point and dimensionless number with a qualitative interpreted concept and definition with using water quality indices. NSF water quality is the most widely applied index which is used. The present project was carried out to determin Gargar river, sw Iran, water quality using NSF as a water quality index. Hence, 10 sampling stations were set up along the river mainstream and water samples were collected from these stations during 6 months (from December 2009 to June 2010), monthly; and 9 parameters including water temperature, turbidity, fecal coliform, NO3, TS, PO4, pH, DO, and BOD were measured. Finally, the results were analysed using NSFWQI. Results of this study indicated that the quality of the river water was categorized in medium and bad classes in all parts of the river. Moreover, the results of NSFWQI showed that "after Chamfaraj" station, which is located at downstream of some aquaculture complexes, with the average index value of 51.5, and the "Bandemizan" station, which islocated at upstream and before entrance of the waste waters from different land uses with the average index value of 57.5 had the worst and the best conditions among the other stations, respectively, during the period of the study. In general, water quality values of the stations varied from 48 to 60. In general, results of the current study indicated that the degree of influence of pollutant sources, especially aquaculture effluents, on water quality of Gargar River is high in the different parts of the river. However, due to self purification property of this river, a relatively acceptable water quality is achieved in the downstream of the river. In conclusion, improvements in the water quality of Gargar river is required an accurate management of different land use's effluents and reducing their pollution loads.