Abstract:
Despite large potential for surface irrigation development, only few percentages of suitable
area have been utilized in Ethiopia. This study evaluated the physical land suitability of
surface water irrigation for small-scale irrigation development (<200 ha) in the study area.
The potential was examined by considering various interacting physical factors, such as
river proximity, nature of soil type, land use/cover, and slope gradient factors with a spatial
modelling-based multi-criteria evaluation (MCE). The relative importance of each factors in
an overall suitability process were determined based on relevant literatures and expert’s
estimation to produce the resultant suitability maps of the study area. The results of this
study indicated that nearly 2254 ha (6%) of the study area were classified as suitable for
surface water irrigation. The findings also revealed that about the largest percentage, i.e.,
21737ha (58%) of the study area were classified as moderately suitable. This was largely
due to physical limitations such as existing topography and spatial proximity in surface
water source. On the other hand, irrigation activities practiced in the study area are largely
characterized by traditional water diversion structures, which are often traditional, prone
to water wastage and less efficient schemes of lower productivity and poor market linkage.
Therefore, the irrigation potential in the study area can only be met by increasing dry season flows (following watershed management in the upstream), increasing water use efficiency thereby decreasing water use wastage, and provision of adequate extension service
for small scale irrigation scheme holders.
