ABSTRACT summary of a research main findings The rapidly growing population in drought-prone areas with high rate of urbanization demands the identification and management of groundwater resources. In the Welmel catchment, a search for an alternative source of water has been always a major issue. The current practice of groundwater potential zone (GWPZ) identification is time-consuming and uneconomical. This study applied integration of GIS-remote sensing (RS) and analytical hierarchy process (AHP) for mapping the GWPZ of Welmel catchment, Southeast Ethiopia. This technique is a fast, accurate, and feasible technique and the GWPZ influencing parameters were derived from Operational Land Imager 8, digital elevation model (DEM) 30 × 30 resolution and secondary sources were utilized in this research, such as geomorphology, lineament density, lithology, rainfall, drainage density, slope, elevation, land use/land cover (LULC), and soil texture were prepared. Borehole data were used for results validation. All thematic layers were reclassified, then the weight for each factor was assigned according to their relative importance as per suitability based on Saatty's scale of AHP. The result showed that geomorphology and lineament density have a higher weight and soil texture has the lowest weight for identifying GWPZ. For weights allocated to each parameter, the consistency ratio obtained was 0.061, which is less than 0.1, showing the weight allocated to each parameter is acceptable. The resulting GWPZ of the study area indicates four zones representing very low, low, moderate and high. The areal extent of high and moderate GWPZ is 350 and 2,256 km2, respectively. Low and very low GWPZ covers 10,356 and 1,547 km2 areas. The particular direction of groundwater flow is towards the NE and SE, coinciding with the direction of surface water flow. The validation result of 82.08% confirms the very good agreement among the groundwater record data and groundwater potential classes delineated.
Tesfaye et al. (Tue,) studied this question.