Investigation of Corrosion Potential and Precipitation Tendency of Drinking Water in the Kerman Distribution System

Occurrence of corrosion and deposition in drinking water in distribution system can leads to economic and health damages. The aim of this study was to investigate the corrosion and precipitation potential of drinking water in Kerman distribution system. This cross-sectional study was performed from September to November of 2011. For determining the chemical quality of Kerman drinking water, 40 samples with 2-4 L were taken in glass container and then were analyzed. The physical and chemical quality of samples was determined and the potential of corrosion and precipitation of waters were analyzed in terms of four corrosion indicesie. Langelier Index (LI), Ryznar Index (RI), Pockorius Index (POI) and Aggressiveness Index (LS). The test methods were adopted from “standard methods for water and wastewater examination” and the obtained data were analyzed with description parameters. Based on the results, chemical quality of water in Kerman Distribution system was under the Iranian national standard and WHO guideline. The results showed that the LI index for >90% was above zero and RI index indicated that >82% of samples was below 7. According to POI and LS index, the deposition rate was 60 and 90%, respectively. By survey of LI, RI, POI and Ls indexes, it was found that Kerman distribution system water has scaling (precipitation) potential. The chemical quality of Kerman distribution system water is imbalance thus resulting in the scale formation in water distribution system and other equipments. In addition, to stop economical loss the planning for water quality stabilization is necessary.