Performance assessment of water conveyance and application efficiency in the Lower Areb Small Scale Irrigation Scheme Amhara Region Ethiopia

Ethiopia has made a large investment in an irrigation project to improve the food security of the country. However, many irrigation schemes still operate below their intended objective due to inefficiencies in water conveyance and on-farm water use. This study assessed the efficacy of water conveyance and application within the Lower Areb Small-Scale Irrigation Scheme in the Amhara Region, Ethiopia, to identify principal performance limitations and offer practical, evidence-based management recommendations. The study was carried out during the 2018 irrigation season (March – May), employing a mixed-methods approach. Primary data were obtained through direct measurements of canal flow, soil moisture sampling conducted prior to and following irrigation, comprehensive field observations, and structured interviews with 120 randomly selected farmers from a total of 172 irrigation users. The primary factors we examined included the volume of water entering and exiting the canal, the moisture loss from the soil, the profundity of irrigation, and the locations of the farms within the command area (head, middle, and tail). We used Microsoft Excel, stata software, and the ArcGIS 10.1 tool for data analysis and for spatial assessment of the study. The results of the main canal show that it performed relatively well, with a conveyance efficiency of 91.49%, indicating limited transmission losses of 8.51%. In contrast, water application efficiency was low and unevenly distributed across the scheme, averaging 49.5% at the head, 47.5% in the middle, and 52% at the tail, resulting in an overall scheme efficiency of only 45.43%, which is well below internationally recommended standards. The satisfaction level of irrigation users with the irrigation service received were 62.5%, 47.5%, 42.67% and 40% at the head, middle, tail reaches. The main factors affecting the performance of the scheme were farm’s location relative to canal, irrigation scheduling, and field-level control structures. This study’s findings are important for targeted interventions for canal maintenance, farmer training on irrigation scheduling, and maintenance of on-farm water control infrastructure. This study is crucial for improving crop productivity, irrigation system sustainability, and long-term food security and climate resilience. The overall performance of the scheme is low. Therefore, improving the irrigation scheme’s performance is critical for enhancing crop productivity, ensuring the sustainability of the irrigation scheme, and ensuring long-term food security and climate resilience.