Assessment of water quality of the Parvaz River using the EPT and Hilsenhoff bioindicators, in Chaharmahal & Bakhtiari Province

The present study was conducted to identify pond effluent effects on macroinvertebrate communities of the Parvaz River, located in Chaharmahal & Bakhtiari Province, Iran. Additionally, in order to assess the river's water quality, EPT and HFBI indices were employed. Macroinvertebrates sampling was performed monthly from April 2014 to the end of March 2015. Macroinvertebrates were sampled using the Surber Sampler, with three repetitions at each station. The results of the Hilsenhoff biotic index showed that the level of this index ranged from 4.02 to 4.5. Based on the results of the Hilsenhoff biotic index, the water quality of the Parvaz River was in very good status (possible slight organic pollution) and good status (some organic pollution probable) in April and other months, respectively. The levels of the EPT index showed statistically significant differences in studied stations. Furthermore, downstream stations, especially stations 4 and 5 showed lower EPT values. In conclusion, based on the results of the studied indices, the water quality of the Parvaz River in all investigated stations ranks among rivers with high self-purification, with the exception of the last station.