MULTI-INFLUENCING FACTORS ASSESSMENT TO MAP THE GROUNDWATER POTENTIAL ZONES IN THE SOUTHERN DESERT OF IRAQ

Abstract

The reliability of deep aquifers makes groundwater a vital resource in semi-arid and arid regions. However, less precipitation and more droughts are predicted due to climate change. Iraq has been significantly affected by a prolonged drought, leading to a notable increase in groundwater use over the past decade. Consequently, utilizing groundwater has emerged as the most viable option for meeting water supply requirements. This study aims to construct a groundwater potential map (GPM) for the Dammam confined aquifer in Iraq's southern desert zone using integrated RS, GIS, and multi-criteria decision-making (MCDM) approaches, including the analytical hierarchy process (AHP) to facilitate groundwater management. A multiclass GPM is created by extracting relevant thematic layers based on factors that influence groundwater potential and integrating them into a normalized Pairwise comparison matrix using the AHP technique. The findings of this study demonstrate that the created GPM classifies the study area into five zones, including very good, good, moderate, poor, and very poor groundwater potential zones (GWPZs). The distribution of these zones as a percentage of the total area of 76732.71 Km2 is as follows: 15.91%, 39.02%, 33.01%, 6.49%, and 5.57%, respectively. The AHP method accurately delineates a groundwater potential map with 85.4% accuracy. Specifically, out of 349 well locations, 298 were correctly identified using this method. Such a study will significantly contribute to early planning of groundwater exploration by providing preliminary, reliable information on the optimal zone before drilling, especially in arid areas with limited groundwater information, to target appropriate drilling sites for groundwater wells