Abstract:
Ahero Irrigation Scheme in Kenya grows rice under irrigation. The current state of the
scheme is unsatisfactory because of poor performance. It is important to evaluate the
scheme to come up with measures that will assist the scheme’s managers to better
understand the system they control to bring about improvements. The main objective
of this study was to apply the IPTRID benchmarking indicators in performance
assessment of Ahero Irrigation Scheme. The specific objectives were to: determine the
hydraulic performance of the irrigation system; evaluate the financial performance of
the irrigation system; and assess the rice crop-water productivity performance of the
scheme. The research study employed both quantitative and qualitative research
designs. The primary and secondary data types were collected. The random sampling
technique was employed in data collection. Specialised software was used in data
analysis. The hydraulic performance evaluation found that the earthen main canal of
length 14.3km lost 16.8% of the irrigation water as conveyance losses. Some of the
water control structures like division boxes and sluice gates along the main canal were
not functioning properly because they were aged or vandalized. The financial
assessment found that the operation and maintenance revenue collected from farmers
covered 22.2% of the expenses incurred in offering irrigation and drainage services.
The energy cost was the biggest accounting for 54.7% of the total expenditure. The rice
crop-water productivity for the scheme was 0.341kg/m3 and was found as poor because
of conveyance losses and field application losses of irrigation water. The study
concluded that substantial amount of irrigation water was lost as conveyance losses.
The water control structures were not functioning properly. The operation and
maintenance revenue collected from farmers could not sustain expenses incurred in
offering irrigation and drainage services. The rice crop-water productivity for the
scheme was low. This study recommends that; the earthen main canal be lined with
impermeable lining, water control structures be rehabilitated, collected revenue be
reviewed, alternative or supplementary sources of energy be developed, and irrigation
water be supplied via gravity. Further studies should be conducted to determine the
effects of sediments carried by pumped irrigation water on performance of the electric
pumps.
