Delineation of groundwater potential zones using remotely sensed data and GIS-based analytical hierarchy process: Insights from the Geba river basin in Tigray, Northern Ethiopia

Study region: The study was undertaken in the Geba Drainage Basin, major tributary of the Tekeze Drainage Basin in Northern Ethiopia. Study focus: The objective of this study is to identify the groundwater potential zones of Northern Ethiopia's Geba Drainage Basin. Nine groundwater indicators were used as inputs, including li- thology, geomorphology, lineament density, drainage density, slope, elevation, land use and land cover, rainfall, and soil. According to their relative influence on groundwater potentiality, the thematic layers and their classes were assigned appropriate weights based on Saaty's 1-9 judg- ment scale. The assigned weights were then normalized using an Eigen vector-based Analytical Hierarchy process. By superimposing all the normalized layers in the GIS environment, a groundwater potential map was developed.New hydrological insights for the region: Five distinct groundwater potential zones-very good, good, moderate, poor, and very poor were found in the study area. The areal distribution showed that majority of the area (45%) fell within the poor groundwater potential zone. The groundwater potential zones of moderate, very poor, good, and very good cover approximately 27%, 12%, 10%, and 6% of the total area, respectively. The results were compared to the groundwater yield of boreholes collected from the study area. The validation analysis revealed a 72% similarity, which is representative. The employed method is therefore a reasonable option for groundwater development in the Geba Drainage Basin.