“A multi-method approach to groundwater potential assessment: Integrating remote sensing, GIS, and AHP in North Shoa zone, Ethiopia”

Abstract

Groundwater is essential for human health, economic development, and ecosystem sustainability, particularly in water-scarce regions. In Ethiopia, it supplies over 70% of the national water demand, yet localized assessments remain limited. This study addresses this gap for the North Shewa Zone, where water scarcity is exacerbated by low rainfall, reliance on rain-fed agriculture, and rapid population growth. By integrating Geographic Information Systems (GIS), Remote Sensing (RS), and the Analytical Hierarchy Process (AHP), we developed a groundwater potential map using thematic layers such as geology, lineament density, land use/land cover, slope, rainfall, drainage density, and soil type. For validation, well location data were obtained from the Ministry of Water and Energy, and a three-month field survey (15 February – 15 May 2022)was conducted to verify well locations and directly measure water yields from 31 boreholes (1). Despite challenges such as incomplete historical water yield records and non-functional water meters, the results indicate that 0.5% (80.8 km²) of the study area has Very High groundwater potential, 24.7% (3994.5km²) High, 58.8% (9505.56 km²) Moderate, and 15.9% (2505.16 km²) Very Low (2). Validation through Receiver Operating Characteristic (ROC) curve and Area Under the Curve (AUC) analysis yielded an AUC of 0.89, demonstrating strong agreement with borehole yield data (3). This confirms that integrating Remote Sensing and GIS is highly effective for delineating groundwater potential zones. This study provides a cost-effective, scalable, and reliable method for groundwater assessment, offering actionable insights to improve irrigation and potable water supply in North Shewa Zone.