A study on corrosion and scaling potential of drinking water supply resources in rural areas of Sarvabad, West of Iran

Corrosion is a physicochemical reaction occurring between the metal and its surroundings, which usually has an electrochemical nature and results in changes in the properties of the metal. The corrosive water dissolves the pipe’s material during flowing and this causes many problems. This study investigated the potential of corrosion and scaling of 46 water supply resources in the villages of Sarvabad, west of Iran during high-water (HW) and low-water (LW) periods. Parameters including pH, temperature, alkalinity, calcium hardness, and total dissolved solids (TDS) were measured and the Langelier, Rayznar, Aggressive, and Puchorius indices were calculated using the data collected. The zoning maps for the indices were prepared using ArcGIS (Ver. 9.3) software. The results showed that the mean value and standard deviation for the Langelier index were 0.23 and 0.28, respectively, while for the Rayznar index, they were 7.12 and 1.18, respectively. The values for the Aggressive index and Puchorius index were 11.6 and 1.84, and 7.03 and 1.45, respectively. The Langelier index in some water supplies showed a tendency to dissolve calcium carbonate, and meanwhile in some areas it tended to precipitate calcium carbonate. Moreover, based on the Rayznar index value, water potential for corrosion increases in steel pipes; based on the Aggressive index, the potential for corrosion is medium, whereas based on the Puchorius index, there is a potential for corrosion. A brief description about the zoning maps is also given.