Qualitative zoning of the Talar river by OWQI index and GIS system

rivers are one of essential resources for preparing water for various applications such as agricultural, drinking and industrial. by regarding the importance of this issue and drought of the recent years, keeping of these resources is our important duty. on the other side, these resources were used as a place for discharge of wastewater, industrial and agricultural swage. by considering of this fact that each river has a certain capacity for receiving inlet pollution, today, qualitative and environmental investigation of these resources seems crucial. if we find points of the river where qualitative parameters of water are below the standard limitations, finding of critical points and appropriate solution of treatment will be simple. so, by qualitative investigation of rivers water, most of the risks and problems will be controlled. for removal of these dangers, qualitative index of water is proposed which use raw data and estimate water quality and categorize the value of water quality by issues. in this study, the water quality index of national health institutes and its equations have been introduced and then, the water quality of TALAR river at up-side, middle-side and down-side of the river during two periods of rainy seasons and drought seasons have been investigated and compared with each others. the measuring methods of parameters were based on standard methods. the calculated values for water quality index at 3 stations of up, middle and down-side in rainy seasons were obtained 19, 15 and 17, respectively, and these values in drought seasons were 18, 18 and 17, respectively. by regarding the tables of OWQI index, all of these values are at very bad classification and they are not suitable for drinking purposes.

water quality, OWQI index, GIS, TALAR river, zoning