Assessment of The Hydraulic Performance of Kesem Irrigation scheme , Afar , Ethiopian
Creators: name: Senait Teferi Tewachew
Publisher: name: National Academic Digital Repository of Ethiopia
Year: 2020
Subjects: Current meter, CROPWAT, Water delivery performance, Kesem Sugar Factory Irrigation Scheme, Irrigation water supply and demand

description: This thesis was done with the purpose of identifying and understanding the current<br> level of the hydraulic performance of Kesem Irrigation Scheme. The indicators of<br> adequacy, efficiency, equity, dependability were used to determine water delivery<br> performance. To evaluate those indicators primary and secondary data were used.<br> Secondary data such as climate, agronomic, soil data were taken from Kesem<br> Meteorological Station and Kesem Sugar Factory Office. Primary data which were<br> collected through field measurements and field observation were also taken. This<br> study was carried out during the irrigation season from January to March, 2020.<br> CROPWAT 8.0 software, and Micro soft excel sheet were used to analyze the<br> collected data. Water delivery indicators were evaluated by assessing irrigation water<br> supply versus demand from selected secondary canal off takes. The conveyance<br> efficiency and losses were carried out using inflow-outflow method in the main and<br> secondary canal. Flow of canals were determined using Area-Velocity method by<br> determining canal cross sectional area and flow velocity using AA current meter. To<br> evaluate the water delivery indicators five secondary canal off takes were taken and to<br> determine conveyance efficiency of the scheme 10 canal segments were also taken<br> from the upstream, middle and downstream reach of the main canal. From the<br> analysis of the study, irrigation water supply was exceeding the demand was during<br> the study season. The evaluations of this study showed that the overall efficiency (PF)<br> and equity (PE) are poor this shows that the water supplied to each off takes was in<br> excess of the required but it is not distributed judicially among the end users. On the<br> other hand adequacy (PA) of water distribution and dependability (PD) of the water<br> supplied in the system rated as good and fair respectively. From the analysis of the<br> study, irrigation water supply was exceeding the demand was observed during the<br> study season. This was at upstream, middle and downstream by 87.8, 56, and 90%<br> respectively. The overall average main and secondary canals conveyance efficiency<br> was 61.8 and 62 % and conveyance loss of 1.06 and 0.08 m3/s/km respectively which<br> were below recommended values. These results indicates that non proportionality of<br> irrigation water demand with supply, poor water delivery system, absence of flow<br> measurement, absence of frequent and proper maintenance, and the management<br> aspects were problems strongly affecting the hydraulic performance of the scheme.<br> Therefore, it is suggested that, adequate maintenance and suitable management<br> approaches, maintain unfunctional flow control, install flow measurement structure at<br> each secondary canal off takes are required to improve the irrigation system<br> performance. The conveyance systems should be improved through regular canal<br> cleaning and maintenance of infrastructure and control illegal water theft is basic<br> remedial measures