Current and Future Irrigation Water Requirement and Potential in the Abbay River Basin, Ethiopia

Abstract

In this study, we evaluated the present and future irrigation potential and irrigation water requirement (IWR) in Ethiopia’s Abbay River Basin using the MIKE HYDRO River modeling software. Relative changes in IWR were determined and analyzed at six irrigation nodes for 19 crops and 23 traits. Four irrigation scenarios were compared: low, medium, full (FULL), and high growth (HIGH). Significant IWR changes were observed in FULL and HIGH irrigation scenarios, with highly intensive irrigation conditions resulting in high IWR. The MIKE HYDRO model was used to simulate the IWR historically for two scenarios: (1) scenario representing the current total irrigable cropland (79,800 ha) and (2) scenario projecting the basin’s potential cropland (658,384 ha). As a result, the area under IWR analysis was 738,184 ha. The annual IWR was 9 billion cubic meters (BCM) and 18 BCM in FULL and HIGH irrigation scenarios, respectively. We found that uncertainties in crop migration, cropping patterns, and adaptation rates to climate change significantly affected irrigation and crop production. It is necessary to investigate the effects of HIGH irrigation on yield and economic benefits of FULL irrigation before adopting different irrigation development methods. Further research is required to adapt to changing climate for development of targeted IWR strategies.