DELINATION OF GROUNDWATER POTENTIAL ZONE IN CASE OF DARA DISTRICT SIDAMA RIGIONAL STATE ETHIOPIA

Abstract

Groundwater is a treasured and significant natural resource in the world and it is the most fundamental for the growth and development of one country. Lack of adequate water supply and limitation of information gaps related to groundwater potential zone identification become slow down economic growth and can have negative environmental effects on health and livelihoods. The current study focused on the delineation of groundwater potential zones in case of Dara District Sidama Regional State Ethiopia, applicable to remote sensing (RS) and geographic information system (GIS) analysis techniques. The study approach involved integration of seven different thematic layers (Rainfall, Lithology, Slope, drainage density, Lineament density, Soil texture, land use/cover) based on weights assignment and normalization with respect to the relative contribution of the different themes to groundwater occurrence using analytic hierarchy approach. Following weight normalization and ranking, the thematic maps were integrated using ArcGIS 10.4.1 software to generate the overall groundwater potential map for the study area. Finally, groundwater potential zones are classified into four categories namely very high, high, moderate and low zone. It is observed that 0.59% (1.52km2 of the study area falls under very high) groundwater potential zone, 44.91% (115.77km2 ) under high, 53.81% (138.71km2 ) under moderate and 0.69% (1.79km2 ) categorized under low groundwater potential zone of study area. The prediction accuracy was checked based on borehole yield observed and predicted data of respective locations. The prediction accuracy obtained (82.5%) reflects that the method applied for the present study produced significantly reliable and precise results.