Spatial variability and hydrochemical quality of groundwater of Hyderabad Rural, Sindh, Pakistan

A present study was carried out to examine the quality of groundwater of Taluka Hyderabad Rural, District Hyderabad, Sindh Pakistan. A total of 80 samples were collected during July 2020 and analyzed for 22 different physicochemical parameters. The samples were evaluated for contamination index (C-d) and water quality index (WQI). The groundwater was also analyzed to check suitability for irrigation, using parameters like sodium adsorption ratio (SAR), sodium percentage (Na %), permeability index, Kelly's index, salinity hazard, and Wilcox diagram. The statistical analyses were carried out such as correlation coefficient, cluster analysis, and principal component analysis. The Gibb's diagrams and hydrochemical facies (Piper diagrams) were examined to evaluate the geochemistry of the study area. The results of physicochemical parameters were compared with World Health Organization guideline (WHO). Electrical conductivity (65%), TDS (82.5%), alkalinity (62%), total hardness (77.4%), and Cl- (60%) of samples were above WHO permissible limits. The contaminated index (C-d) of 75% samples showed risk for human health and WQI of 45.0% samples were found in poor to very poor water category. The Piper diagrams indicated Na and K dominance followed by Ca and Mg. Among anions, Cl- was dominating followed by HCO3-. The chronic daily intake (CDI) values were within 0.586-17.877 and higher than threshold value of 1 at a number of sampling stations. The average values of hazard quotient (HQ) were less than 1, but indicated order, Cd > Pb > Cu, and were greater than 1 at some places. The results of groundwater quality indicated that 21-100% were not suitable for irrigation.