Assessment of physical and chemical quality of water resources in Khaf, Taybad, Roshtkhar cities during 2005-2015

  Therefore, this research was conducted with the aim of qualitative monitoring of chemical and physical parameters of groundwater resources of three cities in Khorasan Razavi province. In this descriptive-analytic study, a total of 627 samples were collected from the drinking water wells of Khaf, Taybad and Roshtkhar cities during 2005 to 2015 years based on the standard methods for water and wastewater analysis and 12 parameters including electrical conductivity (EC), carbonate (CO3-2), pH, bicarbonate (HCO3-), sulfate (SO4-2), Chlorine (Cl-) magnesium (Mg+2), calcium (Ca+2), sodium (Na+), potassium (K+), total dissolved solids (TDS), and total hardness (TH) were assessed according to the standard methods. Data were analyzed using Excel and SPSS softwares and water quality was compared to the national standards and WHO guidelines. The results of this study showed that the levels of chemical parameters including magnesium, calcium, sodium, potassium, and pH of Khaf, Taybad, and Roshtkhar cities were within the standard range. The averages of electrical conductivity were 4229, 1724, and 2918 µm/cm, the averages of total dissolved solids were 2664, 1086, and 1838 mg/L, and the averages of chloride were 807, 240, and 578 mg/L in Taybad, Khaf, and Roshtkhar cities, respectively. These results imply that the levels of these parameters exceed the standard limits in Taybad and Roshtkhar cities. The means of hardness of the drinking water sources in the studied cities were 594, 285, and 362 mg/L as CaCO3, respectively. Based on these findings, the drinking water of Taybad and Roshtkhar cities could be classified as very hard water and Khaf's water resources as hard water. Most of the physical and chemical parameters of the Khaf waters are within the national standard, but the waters of Taybead and Roshtkhar in some parameters exceed the standard range