Zabihollah Yousefi - Professor, Department of Environmental Health Engineering, Faculty of Health, Mazandaran University of Medical Sciences, Sari, Iran
Farzad Kazemi - MSc, Department of Environmental Health Engineering, Student Research Committee, Faculty of Health, Mazandaran University of Medical Sciences, Sari, Iran
Reza Ali Mohammadpour - Associate Professor, Department of Biostatistics, Faculty of Health, Mazandaran University of Medical Sciences, Sari, Iran

Background: Scaling and corrosion are the two most important indexes in water quality evaluation.Pollutants are released in water due to corrosion of pipelines. The aim of this study is to assess the scaleformation and corrosion of drinking water supplies in Ilam city (Iran).Methods: This research is a descriptive and cross-sectional study which is based on the 20 drinking watersources in Ilam city. Experiments were carried out in accordance with the Water and Wastewater Co.standard methods for water and wastewater experiment. The data were analyzed by using Microsoft Exceland GraphPad Prism 5. The results were compared with national and international standards.Results: The mean and standard deviation (SD) values of Ryznar, Langelier, Aggressive, Puckorius andLarson-Skold indices in year 2009 were equal to 7.833 (±0.28), -0.102 (±0.35), 11.88 (±0.34), 7.481 (±0.22)and 0.801 (±0.44), respectively, and were 7.861 (±0.28), -0.175 (±0.34), 11.84 (±0.37), 7.298(±0.32) and0.633 (±0.47), for year 2013 respectively. The average of Langelier, Ryznar, Aggression, and Puckoriusindices indicate that potable water resources in Ilam city have the tendency to be corrosive. Statisticalanalysis and figures carried out by GraphPad Prism version 5.04.Conclusion: The results of different indices for water resources of Ilam city revealed that water suppliesof Ilam city were corrosive. Water quality control and replacement of distribution pipes in development ofwater network should be carried out. Moreover, water pipelines should be preserved with several modesof corrosion inhibition.

Corrosion, Scale formation, Water resources, Ilam