A GIS-based susceptibility indexing method for irrigation and drinking water management planning : Application to Chebba-Mellouleche Aquifer, Tunisia.
Résumé
Locating high quality groundwater resources in semi-arid regions with growing population and agricultural development is an expensive undertaking. Simple susceptibility indexing method, based oil vulnerability and quality index, can be used to facilitate this application. The GIS technique provides an efficient environment to reach this objective. The contamination susceptibility index was calculated by taking the product of the vulnerability index (VI) and the quality index (QI). The VI index was calculated using DRASTIC method to evaluate the hydrogeological characteristics of the Aquifer. The quality index calculation procedure, based on the water classification, was introduced to evaluate hydrochemical data. The susceptibility indexing method was applied in the Chebba-Mellouleche Aquifer, located in Eastern Tunisia. The results show a clear degradation of the water quality throughout the Aquifer. In addition, the susceptibility indexing map which incorporates hydrogeological and hydrochemical datasets reveals a similarity with areas of high anthropogenic activities. Thus, it is more realistic to estimate the groundwater contamination. The main aim of this study is to give an overview of the drinking and irrigation water quality in relation to the hydrogeological characteristics of the Chebba-Mellouleche Aquifer. This overview can form the basis for further investigations