Evaluation of irrigation water allocation for improving water use efficiency and conflict resolution in Hatset irrigation scheme, Eastern Tigray, North Ethiopia

Abstract

Efficient water allocation is crucial for enhancing irrigation water use efficiency and mitigating conflicts among users, especially regions where water is limited. This study tried to evaluate the irrigation water allocation system to optimize water allocation and improve conflict resolution mechanisms in the Hatset irrigation scheme, Eastern Tigray, North Ethiopia. The primary data was collected through soil sampling, flow measurements, household surveys, key informant interviews, and focus group discussions, and the secondary data was collected through meteorological, hydrological and spatial data. WEAP model used to assess current water allocation scenarios and propose improved strategies. Additionally, CROPWAT model was used to estimate crop water demand and HEC-HMS also used to estimate reservoir inflows. The findings reveal, unmet demand 0 m³, 0 m³, 895,360 m³ and water losses 155,721 m³, 309,160 m³, and 430,479 m³, head, middle and tail-end users respectively. Three scenarios were analyzed: a reference scenario, an improved water use efficiency scenario, and an irrigation expansion scenario. The reference scenario was business-as-usual approach and the enhanced water uses efficiency scenario demonstrated a 37.5% reduction in water demand by incorporating canal lining, efficient scheduling, and efficient irrigation techniques and the irrigation expansion scenario, which increased the irrigated area but resulted in a 23% increase in water demand with no unmet demand. Moreover, the study investigated the effect of efficient water allocation in resolving conflicts within the Hatset irrigation scheme, where infrastructure issues and governance gaps created significant disparities. It conducted how inadequate access for tail-end users caused conflict, while traditional and formal mechanisms proved ineffective due to poor coordination. The proposed hybrid approach, which integrated community driven and IWUAs, addressed systemic challenges and promoted sustainable conflict resolution.