Application of GIS for Predicting Quality of Underground Water for Drinking

Gaziantep is located at the south-east part of Turkey. Drinking water needs of Gaziantep city are increased because of population in last decade. Some amounts of drinking water are supplied to Gaziantep from underground. Because of large amount of industrial areas and settlement, quality of ground water is decreased in years. Therefore governors of the city should know which part of the city has a potential of having good quality of drinkable underground water. In this study, 9 wells in the city centre area of Gaziantep city are determined and water samples were taken from these wells. Then water samples were analyzed in the laboratory of GASKİ (Gaziantep Water and Sewage Management). The laboratory results of underground water from each well are entered to ArcGIS program with the digital elevation map of Gaziantep to predict the quality of the underground water of Gaziantep. The ArcGIS program produced quality maps of drinkable water in Gaziantep. These maps show the dynamic and static water levels in the well, pH level, bromide, sulfate, free chlorine, hardness, turbidity, nitrate, and fluoride. This study shows that ArcGIS program is very useful tool to make the quality maps of groundwater for a specific area.