ORIGINAL ARTICLE Hydrochemical characteristics and groundwater quality assessment in Bushehr Province, SW Iran Ramin Sarikhani 1 • Artimes Ghassemi Dehnavi 1 • Zeinab Ahmadnejad 2 • Nasrollah Kalantari 3 Received: 19 July 2014 / Accepted: 10 June 2015 Ó Springer-Verlag Berlin Heidelberg 2015 Abstract The chemical quality of groundwater of Bushehr, southwest of Iran, was assessed for its suitability for drinking purposes. Hydro-geochemical studies were carried out in this area to identify the geochemical processes and their relation to groundwater quality. A total of 19 water samples were collected from the aquifer. The samples were then analyzed for different physicochemical properties, such as pH, total dissolved solids (TDS), total hardness (TH), calcium, mag- nesium, carbonate, bicarbonate, sulfate, and chloride con- centrations. In this study, the average TDS content was in the range of 4419–10,066 mg l/l, and other important parame- ters of water, such as TH (1200–3500 mg l/1) and chloride (1046–3855 mg l/1), were also higher than the maximum permissible limits specified by WHO. On the basis of con- centrations of major elements, studies of the study area showed that the total samples collected are unsuitable for drinking. Linear increase in sodium and chloride of the total dissolved ion indicated a dissolution of halite in the study area. Salinity of the aquifer is mainly a result of the Dalaki River recharge, dissolution of evaporated minerals intrafor- mation, and also agricultural returned water. The dissolution of evaporite minerals, such as halite and gypsum, has increased the concentration of total dissolved solids and of sulfate in the Shahpour River and also groundwater entering the study area has caused salinity in this river. Keywords Chemical quality Á Salinity Á Evaporate Á TDI Introduction Salinity plays an important role in water resources developments and management throughout the world, particularly in arid and semiarid areas. Salinization of groundwater in arid and semiarid regions, as a limiting factor of use, has a strategic importance (Zarei et al. 2013). The largest source of Cl - in the Earth’s crust is the mineral halite in evaporate deposits, which formed over geologic time by the evaporation of seawater. The salinization of groundwater is one of the major causes of water quality deterioration affecting the sustainable use of groundwater, since it places limitations on the use of the water for urban water supply and agricultural use (Ahmed et al. 2013). Salinity is an important determinant of the suitability of water for drinking, irrigation, and industrial use (Wurbs 2011). Saline contamination may occur due to evaporate- domes leaching in groundwater (Ribeiro 1999). In several areas, salt contamination of groundwater has reached such a level that many of the wells have been abandoned (Cotecchia and Polemio 1999). Predicting the location and quality of groundwater in such environments is difficult unless an understanding is achieved of the source of salts in such water, and of the chemical processes that modify its composition through time. Salt sources, and the means of producing saline groundwater, have been discussed earlier (Beeftink and Nieuwenhuize 1986; Lee 2010; Mori 1985; Polemio et al. 2008; Wurbs et al. 1993; Zarei et al. 2013, 2014) and others. The principal sources of salts in any continental area are (1) sea water stranded in internal basins by marine regressions; (2) connate water of marine origin released by weathering from the pores of marine & Ramin Sarikhani Sarikhani.r@lu.ac.ir; Sarikhani_r@yahoo.com 1 Department of Geology, Lorestan University, Khorramabad, Iran 2 Department of Earth Sciences, Tabriz University, Tabriz, Iran 3 Faculty of Earth Sciences, Shahid Chamran University, Ahvaz, Iran 123 Environ Earth Sci DOI 10.1007/s12665-015-4651-9