Evaluation of the corrosiveness and precipitation potential in the drinking water supply wells of Gorgan city

Abstract

AbstractIntroduction: Corrosion and precipitation are two problems of water quality management for the water transmission and distribution systems. Hence, the present research was conducted to investigate the potential of corrosiveness and precipitation in the drinking water supply wells of Gorgan city using some indicators.Methods: Here, the results of chemical analysis of 63 wells supplying drinking water in spring and autumn were used. First the temporal and spatial changes of physicochemical parameters were investigated using one-way variance statistical test and IDW method, respectively. The dominant type, the origin of chemical ions, and their evolution process in Gorgan aquifer were studied. In this research, water hardness, LSI, RSI, CR and LS were used to determine the corrosion and precipitation potential of drinking water in Gorgan city. Finally, the temporal and spatial changes of indices calculated in two seasons were investigated.Findings: The high concentration of calcium ions in groundwater, due to the recharge of the aquifer by the limestone series located in the southern highlands, has increased its hardness. The results of RSI and LSI revealed that the majority of wells are corrosive and their water has the potential to decompose CaCO3. Also, the corrosive property of water in the direction of groundwater movement is significantly reduced and the water precipitation property is increased. Also, 90 and 98% of the groundwater resources of Gorgan city have a corrosion ratio of less than one. Therefore, it is possible to transfer water from most wells with any type of metal pipes.

Keywords

• groundwater
• water quality
• hydrogeochemistry
• water supply facilities
• gorgan city