Land Suitability Assessment of Surface Irrigation Potential in Gilgel Gibe, Omo Gibe Basin, Ethiopia

Abstract

The aim of this study was to assess land suitability for irrigation potential of the Gilgel Gibe I watershed, Oromia Region, Ethiopia. The  input data used to process the model and to achieve the objective of the study were soil, digital elevation model (DEM), streamflow, land  use land cover. To identify potential irrigation land, irrigation suitability factors such as soil (type, texture, depth, and drainage), slope,  land cover land use and distance from water supply were taken into account. Irrigation suitability of each physical land parameters was classified based on the FAO guideline for land evaluation into S1 (highly suitable), S2 (moderately suitable), S3 (marginally suitable) and N  (not suitable) suitability classes. The final potentially irrigable land was identified by weighting all the factors of suitability. Result of  suitability of land evaluation ratings based on the qualitative land suitability for irrigation indicated that, 26.80% (110578.05ha) are highly  suitable (S1), 24.83% (102423.81ha) are moderately suitable (S2), 15.53% (64051.44ha) marginally suitable (S3) and 32.84% (135509.58ha)  are not suitable (N) for surface irrigation systems.