The evaluation of water quality using geographical ınformation systems (GIS) and multi attribute decision making

WOS: 000409920900013In the last century, the demand for freshwater resources continues to grow due to the rapidly increasing population and industrialization. This growing demand requires continuous monitoring and evaluation of the limited freshwater resources. This study investigated the spatial distribution of the groundwater quality of aquifers in the Eskil Basin in the Central Anatolian region of Turkey using physical-chemical data and geostatistical methods. The main purpose of this research was to develop a model (water quality index) to prevent any confusion in terms of water quality determination and determine optimum locations based on high water quality. For the assessment of the groundwater quality, 21 water samples were collected from different irrigation wells in the area and evaluated in terms of vulnerability using Analytic Hierarchy Process (AHP). The water quality index of the study area comprised of 18 sub-criteria (water quality parameters) classified under four main criteria of factors causing vulnerability as follows: (i) Group 1 (ii) Group 2 (iii) Group 3 and (iv) Group 4. The groundwater quality maps were constructed using Kriging method and the water quality index obtained from the AHP model. For each map, seven different semivariogram models were tested and exponential method was determined as the best-fit model by using the root mean square standardized error values. In this study, the groundwater quality index of the zones in both maps was classified as (i) very high (ii) high (iii) moderate and (vi) low water quality. The areas that are excellent for groundwater quality were concentrated in the southwest parts of the study area where the Eskil water quality indeks (ESKI) scores were greater than 0.075