灌漑・排水システム工学

Irrigation Potential Assessment on Shaya River Sub-Basin in Bale Zone, Oromia Region, Ethiopia

Abstract

Nasir GT, Tamane AD and Tolera AF

The primary objective of this study was to assess the land resources potential of the Shaya River sub-basin in the Bale Zone of Oromia for irrigation and providing a geo-referenced map of these resources. Watershed delineation, identification of irrigable land, and estimation of surface runoff and irrigation water requirements were the steps followed. Irrigation suitability factors such as slope, texture, depth, drainage characteristics, land use/cover and distance to water source were taken in to account to identify irrigation suitability. The suitability analysis of the parameters indicates that 66.38% slope, 98.20% soil, 92.93% land use/cover of the study areas classified as potentially suitable for irrigation development in the study area. By weighing analysis of all parameters 22.05% of the study area was found to be highly suitable, 25.27% moderately suitable and 16.20% marginally suitable whereas about 33.57% restricted for irrigation developments. By comparing the required water and available monthly flow of the river, the river has the capacity for the application of the command area.