The Awash River (sometimes spelled Awaash; Oromo: Awaash or Hawaas, Amharic: ዐዋሽ, Afar: Hawaash We'ayot, Somali: Webiga Dir, Italian: Auasc) is a major river of Ethiopia. Its course is entirely contained within the boundaries of Ethiopia and empties into a chain of interconnected lakes that begins with Lake Gargori and ends with Lake Abbe (or Abhe Bad) on the border with Djibouti, about 100 kilometres (62 mi) from the head of the Gulf of Tadjoura. The Awash River is the principal stream of an endorheic drainage basin covering parts of the Amhara, Oromia and Somali Regions, as well as the southern half of the Afar Region. The Awash River basin, spanning 23 administrative zones, covers 10% of Ethiopia's area. The basin usually has two rainy seasons, a shorter one around March (Belg), and a longer one between June and September (Kiremt), which partly fall into one longer rainy season. Climate change is predicted to increase the water deficiency in all seasons and for parts of the basin, due to a projected increase in temperature and decrease in precipitation. The Awash River basin is the most developed, utilized, abused, impacted, and most populous (over 15% or nearly 18.6 million out of 120 million) basin in Ethiopia (as of 2021). Rapid growth of agriculture, industries and urbanization within the basin, as well as population growth is placing increasing demands on the basin's water resources. The main sources of water pollution in the upper Awash basin come from industrial and urban wastes, agricultural runoff (pesticides, fertilizers), and sewage discharge. Polluting industries in the basin include tanneries, paint factories, slaughterhouses, textiles, breweries, soft drink factories, sugar factories, hospitals, and pharmaceuticals. The Awash Valley (and especially the Middle Awash) is internationally famous for its high density of hominin fossils, offering unparalleled insight into the early evolution of humans. "Lucy", one of the most famous early hominin fossils, was discovered in the lower Awash Valley. For its palaeontological and anthropological importance, the lower valley of the Awash was inscribed on UNESCO's World Heritage List in 1980.
