Identification of groundwater Potential Areas Using GIS and MCDM in arid and Semi-Arid Regions (Case Study: Nayband in Iran)

Groundwater is an important and essential resource in dry and semi-arid regions, as well as in areas with restricted access to surface waters. Global water demand has increased significantly in recent years, largely due to industrial growth, population growth, and shifts in lifestyle and consumption habits. At present, groundwater is a primary source of freshwater, making up around 34% of the total annual global water supply. Water harvesting is a critical and essential part in infrastructure and economic projects, requiring significant investment. Therefore, it is vital to assess this issue for the sustainable management of groundwater systems. Since groundwater operates dynamically, it is essential to employ Geographic Information System (GIS) in the development and management of groundwater. Multi-Criteria Decision Making (MCDM) analysis including commonly used types such as AHP, is an effective technique in this regard. The main objective of this study is to locate potential groundwater areas in Nayband Plain, Tabas County, using GIS and multi-criteria decision-making analysis. The fuzzy-AHP method was employed to create the groundwater potential map. Various features such as slope, geomorphology, soil characteristics, lineaments, land cover type, precipitation and river distance were used to generate the groundwater potential map. Pairwise comparison of criteria and expert opinions were utilized to assign scores and weights to each groundwater potential criterion. Subsequently, the criteria were categorized, and weights were assigned to each category. Using these weights, final maps were generated using ArcMap 10.8 software. The level of groundwater access in the region was qualitatively classified into five categories: very good, good, moderate, poor, and very poor. To validate the generated map, data from 10 wells, 3 qanats, and 4 springs in the Nayband region were utilized. In conclusion, the comparison of the final map with the distribution of wells, springs, and qanats indicates that this method exhibits high accuracy in this area and contributes to the analysis of the groundwater potential of the region.