Assessment of surface and groundwater quality of Latian dam catchment using water quality index

Surface and groundwater are important vital resources around the world. This study examines the quality of surface and groundwater resources in the catchment area of Latian Dam during the years 1396 to 1398 using GIS tools and water quality indices.
materials and ways  In order to evaluate the quality of water resources, samples were taken from 10 selected stations in two rainy and low rainfall seasons during three years and the physical, chemical and microbial parameters of the samples were evaluated. Then, using water quality indicators and hydrogeochemical characteristics, the quality of water resources was determined and the zoning map of the indicators was prepared using ArcGIS software. The resulting hydrogeochemical data were also interpreted using Piper, Schuler, Wilcox graphical diagrams and statistical analysis.

The results show that on average, during the rainy seasons, the whole region had good quality (30.644). For surface water stations, 3 stations in high rainfall season were of excellent quality (44.243), 2 stations in low rainy season were of excellent quality (40.145) and other stations were of good quality (69.92). According to the piper diagram, the samples are in two states Ca-Mg-SO4-Cl and Ca-Mg-HCO3 and the results of the study of cation and anion combination are mainly Ca-Mg-HCO3. Correlation coefficient between the main variables, there was a significant relationship between IRWQIGC groundwater and its GWQI (r = 0.87) and between IRWQISC surface water and its WQI (r = 0.68) but there is no significant relationship between groundwater and surface water quality. The average groundwater quality during the study period was good (29.143).