Evaluation of groundwater quality and assessment of scaling potential and corrosiveness of water supply networks, Iran

The aim of this study was to determine the corrosion and scaling potential of water supply sources in a province in eastern Iran. In this cross-sectional study, 879 samples were taken to evaluate the water quality characteristics during 12 months (2013-2014). Five indices, Langelier, Ryznar, Puckorius, Larson-Skold, and Aggressiveness, were programmed in Microsoft Excel. The results illustrated that the values of the Langelier saturation index, Ryznar stability index, Puckorius scaling index, Larson ratio, and Aggressiveness index were 0.33 (+/- 0.17), 7.36 (+/- 0.37), 7.4 (+/- 0.6), 2.1 (+/- 1.4), and 12.03 (+/- 0.18), respectively. According to the Ryznar index (RSI), the index for the water resources of Torbat city was 6.99 and RSI for the central part of Gonabad was 6.4 (consolidation grade). The average pH in the studied water wells was 8.03. The amounts of turbidity, calcium, magnesium, nitrate, and fluoride in the study areas have favorable and acceptable conditions. However, the values of sulfate, total dissolved solids, and chloride in a few cities were higher than the standards. Comparison of five stability indices demonstrated that water in some parts of the study area is corrosive. Based on the results, selecting the best method to prevent the corrosion process is required.