Investigating the Optimal Use of Wastewater Treatment Plant in Zanjan

With considering to water crisis in Iran, one of the useable water resources is the wastewater of municipal treatment plant [1]. Water quality indices can be used to figure water threats out and also help to better water resources management [2]. The wastewater quality in out of Zanjan‟s treatment plant, purification potential of Zanjanrood River and treated wastewater feasibility for agriculture plan has been investigated. In addition, the water quality of the river was evaluated based on the National Water Quality Index (NSFWQI) and Iranian Surface Water Quality Index (IRWQIsc). Sampling from Zanjanrood River (1398-1398) was seasonally carried and 16 physical, chemical, and biological parameters were measured in 5 stations. The results showed the mean of water quality is Moderate and Poor class based on the NSFWQI and IRWQIsc index, respectively, in this area. In addition, the average values of measured parameters have compared with their standards and the result showed the treated wastewater can be used as a good source for irrigation plans. The second station had the least of water quality because of treatment wastewater plant site. It is noticeable, the coliform, BOD and nutrient parameters (P, N) were measured in springer and summer more than autumn and winter and this result can be easily showed the impact of human activities on water quality while TDS and COD were vice versa because of flood and erosion in the upstream