Abstract:
In developing countries, one of the best alternatives to consider for reliable and
sustainable food security development is expanding irrigation development. For
countries like Ethiopia where the principal component of project development
(finance) is a constraint to develop mammoth dams for irrigation, small scale
irrigation can be an alternative solution to enhance production. The southern
region as part of the country has been implementing such schemes. Despite
remarkable achievements, some of the implemented schemes have totally failed
and some are performing below their capacity. A case study considering 26
existing small scale irrigation works (1/3 of the total schemes) in the south region
is carried out for this research work and attempt is made to understand the
causes of the major problems that are related to the design consideration of the
different components of the structure and identify the gap in knowledge between
the current design practices and performance of the structures. The pre and post
construction institutional aspects, planning problems, economic problems and operation problems are also given due attention. Some of the many structural
problems in the existing irrigation structures are problems of sedimentation at the
headwork and main canal, problem of seepage through foundation and main
canal, downstream scouring, drying of rivers, damage on impervious and flexible
apron, change of river course, clogging of outlets and damage on CD works.
Likewise, some of the institutional & operation problems are lack of adequate
community participation, water right conflict among up streamers and down
streamers, market problems, proper handing over problem, lack of proper training and the like. The causes for these problems are generally attributed to
the problems in planning, design, implementation and operation of the irrigation
schemes.
