A Geostatistical approach for mapping groundwater quality (Case Study: Tehsil Sheikhupura)

Groundwater is an important source of drinking water especially in rural areas of Pakistan. Therefore, it is very important to assess the quality of drinking water. The present study presents the geostatistical analysis of groundwater quality of tehsil sheikhupura where majority of people reside in rural areas. Groundwater is the only source of water for drinking purpose. The aim of the study is to present the data in GIS environment for better understanding the spatial distribution of each chemical parameter and mapping of the current situation of groundwater quality of tehsil sheikhupura. The most important chemical parameters of groundwater like Sulphate (SO4), Nitrate (NO3), Sodium (Na), Potassium (K), Calcium (Ca), Chloride (Cl), Magnesiurm (Mg), pH, Flouride (F), Total Dissolved Solids (TDS), Hardness, Iron (Fe), Arsenic (As) and Lead (Pb), are selected and compared to the guideline values presented by world health organization (WHO). The geostatistical analysis of these parameters was performed and spatial distribution maps are prepared for each groundwater parameter by ordinary kriging. The semivariogram values are tested and best fitted model for each parameter was selected on the basis of root mean square error (RMSE), average standard error (ASE), root mean square standard error (RMSSE) and mean square error (MSE). The water quality index was developed in order to present the overall water quality of the study area.