Review of Water Conservation Techniques in The Dryland Environment: Focus on Somali Region, Ethiopia

Abstract

Drylands cover more than 40% of the Earth’s land surface and support approximately 2.5 billion people, yet they remain among the most environmentally fragile regions due to low and erratic rainfall, high evaporation rates, and recurrent droughts. Water scarcity in these environments presents significant challenges for food systems, rangeland productivity, and pastoral livelihoods. This narrative literature review examines the current state of knowledge on water conservation techniques in drylands, with a particular focus on the Somali Region of eastern Ethiopia, an arid to semi-arid area where pastoral and agro-pastoral communities face persistent water insecurity. The review synthesizes evidence from peer-reviewed journal articles, policy documents, technical reports, and literature published. A qualitative thematic analysis was employed to identify key patterns, challenges, and opportunities related to dryland water management. The results indicate that the Somali Region’s water crisis results from interacting climatic, biophysical, socioeconomic, and institutional factors. Climatically, the region experiences highly variable annual rainfall ranging 410 mm-510 mm, accompanied by increasing temper atures. Bio-physically, approximately 61% of the land is classified as dry and 39% as very dry, with significant erosion risks in relatively wetter areas. Socioeconomic challenges, including widespread poverty, weak institutional capacity, fragmented governance structures, and reliance on trans-boundary water resources, further intensify water insecurity. The review highlights several water conservation strategies suitable for the Somali Region, including in situ rainwater harvesting techniques (e.g., contour bunds, terraces, and conser vation tillage) that significantly improve soil moisture retention, and ex-situ systems such as sand dams, ponds, and rooftop harvesting that enhance drought resilience. Evidence from comparable dryland regions in East Africa shows that integrated watershed management and community-based interventions can improve groundwater recharge, restore degraded landscapes, and strengthen climate resilience. Achieving sustainable water security in the Somali Region, therefore, requires integrated, participatory, and context-specific approaches that combine climate-smart technologies with indigenous knowledge and coordinated institutional governance.