Assessment of corrosion and scaling potential in groundwater resources; a case study of Yazd-Ardakan Plain, Iran

Abstract

The quality of water entering into water distribution network often provides requirements for corrosion and scaling in areas lacking adequate treatment methods, which can cause serious problems. The most commonly used corrosion indices are Langelier saturation index (LSI), Ryznar stability index (RSI), Puckorius scaling index (PSI), and aggressiveness index (AI). This study aimed to evaluate the corrosion and scaling potential of water resources in Yazd-Ardakan Plain, Iran. Therefore, the corrosion and scaling potential of groundwater resources were investigated according to LSI, RSI, PSI, and AI. Spearman rank correlation and spatial autocorrelation (Moran's Index) were incorporated to assess the correlations and source identification of the variables. The Inverse Distance Weighing (IDW) and Contour interpolation techniques were also employed to describe the spatial variability and interpolate the water quality.Results showed that the mean values of LSI, RSI, PSI, and AI were as 0.30±0.31, 7.12±0.57, 9.50±0.69, and 12.74±0.38, respectively. The positive spatial autocorrelation found for all parameters showed that all parameters had a clear and cluster spatial pattern. Moreover, the Spearman correlation indicated that the source of pollution was the same for all water resources.In this study, most of the water resources had low to moderate corrosivity. Although each of corrosion indices depending on the circumstances can be used to describe the water quality, however, the accordance between the analyses of chemical water quality and corrosion indices can give more reliable results.