Converting flood-risk areas to water-resilient and productive dryland production systems: Example of flood water spreading weirs in Ethiopia

The drylands of Ethiopia are faced with recurrent droughts and an increasing frequency of flash floods that lead to disasters and shocks and severe food insecurity and malnutrition, resulting in humanitarian response actions. However, beyond humanitarian response, the strategies for drought and flood risk management, particularly the investment and development opportunities of using floods for dryland farming, are poorly understood. Historical flood risk information and remote sensing tools were used to assess suitable areas for flood recession areas. The tested flood water spreading weir (WSW) practice assisted in converting flash floods that emerge from adjacent mountains to divert and spread over the fields for productive use. WSWs established different farming zones based on the soil moisture regime and nutrient deposition distribution. The approach has enabled pastoralists to produce substantial amounts of biomass and grain during short and long rainy seasons, which would be stored and utilized during succeeding dry months. Highland-to-lowland geomorphological connectivity of landscape segments and characterizing their rainfall conditions can be useful frameworks for flood risk analysis and assessing floodplain farming. This case study suggests that flood risk can be managed through spreading weirs in the form of recession farming, negating the need for recurrent humanitarian response actions. Thus, addressing the knowledge and evidence gaps contributes to an informed decision towards unlocking the opportunities of flood farming to support livelihoods and agricultural development in drought-prone areas.