Physical performance of small-scale irrigation scheme: a case study of Tilku Fetam irrigation scheme, Awi zone, Amhara region, Ethiopia

The present study was aimed to evaluate the performance of Tilku Fetam small-scale irrigation scheme using internal and external indicators, which is found at Banja district, Awi zone, Ethiopia. To achieve the objective of this study both primary and secondary data were collected. The primary data included; soil moisture before and after irrigation, discharge measurement at main and secondary canals, and interview with beneficiaries about the scheme. The secondary data included; climate data, crops grown in the study area, total yield and cost of production. The crop water requirement was estimated using CROPWAT 8.0 model. The conveyance efficiency was evaluated at main and secondary canals and the application efficiency of the scheme was evaluated at head, middle and tail of the farmers’ field. The results indicated that the average conveyance efficiency of main canals and secondary canals were 78.5% and 72%, respectively, and average application efficiency of the scheme was 44%. The comparative performance of the Tilku Fetam irrigation scheme was also carried out and the output per cropped area and output per command area were found to be 1321.45 US$/ha and 726.8US$/ha, respectively. The value of output per unit irrigation supply and output per unit water consumed were found to be 0.38US$/m3 and 0.28US$/m3, respectively. The value of water performance indicators; relative water supply, relative irrigation supply and water delivery capacity of the scheme were 0.992, 0.99 and 0.62, respectively. Performance indicators showed that the scheme was in need of intensive management and infrastructural improvement to enhance productivity and sustainability of the scheme. In addition, adoption of water-saving practices such as deficit irrigation, surge and cutoff application should be conducted to improving the application efficiency and frequent maintenance of water conveyance system can enhance the conveyance efficiency of the scheme.