Systemic determinants of exclusion and inequity in irrigation water allocation in the Awash-Awash Sub-Basin, Ethiopia

In Sub-Saharan Africa, competition over scarce irrigation water is shaped not only by physical water availability but also by institutional arrangements, power relations, information access, and participation. This study investigates the systemic determinants of social exclusion in water allocation within Ethiopia’s Awash-Awash Sub-basin using a mixed-methods approach and Multi-Criteria Decision Analysis (MCDA). Results showed that state farms had the highest Social Inclusion Index (Si = 0.82), followed by private investors (Si = 0.75), Irrigation Water Users Associations (IWUAs) (Si = 0.48), and smallholder farmers (Si = 0.42). Among smallholders, conflict and conflict resolution (Relative Importance Index (RII) = 0.92), power dynamics and trust (RII = 0.89), and knowledge and information access (RII = 0.85) were particularly important exclusion factors. In contrast, actor size (RII = 0.98) and financial constraints (RII = 0.96) primarily constrained IWUAs. The findings indicated that social exclusion is reinforced through four interrelated dimensions: knowledge and communication, participation and representation, resource and financial constraints, and organizational, cultural, and political dynamics. The study concludes that inequitable water allocation is a systemic governance outcome rather than a consequence of physical scarcity alone. The findings also have implications for Sustainable Development Goal (SDG) 6.5, which calls for integrated water resources management (IWRM), by demonstrating the importance of inclusive participation, information access, institutional coordination, accountability, and conflict resolution. Strengthening the organizational and financial capacity of IWUAs, improving transparency in water-allocation information, and establishing inclusive local monitoring mechanisms can support more equitable water governance in the Awash-Awash Sub-basin.