Spatial Distribution Pattern of Water Quality of Pireghar River with Using Water Quality Index (WQI) and Geographic Information System (GIS)

Due to the importance of Pireghar River and discharging of various pollutants in this river, investigation of quality of Pireghar River seems to be necessary. On the other hand, the pollution zoning and give a correct image about quality status of surface water by geographic information system (GIS) to make any management decision with more awareness.

Water samples from 5 station along the river was collected on February 2015, and water quality parameters namely pH, turbidity, temperature, TS, BOD, DO, nitrate, phosphate, and coliforms was examined. Sampling, preparation and analysis of samples was done according to the standard methods. The resulting data was compared with world standards and then analyzed using NSFWQI index and finally path of river was zoned using GIS.

Based on NSFWQI index Pireghar river water quality was fluctuated between good and medium status at all stations. The highest NSFWQI quality index was related to the first station with quality index of 78 and lowest value was related to the fifth station with quality index of 66. As a result, pollution was increased from the first station to the next stations, and water quality has decreased.

In conclusion, for regular management of the river`s water some legislation should be determined and its monitoring program should be continued.