Dawa River (Webiga Daawa)

Course

The Dawa rises in the highlands of southern Ethiopia and flows south-east. It forms part of the Ethiopia–Kenya border and then part of the Ethiopia–Somalia border (Wikipedia: Dawa River). At Dolow on the Somali border it meets the Ganale Dorya, and the two form the Jubba River (Wikipedia: Jubba River). The meeting point, at about 4.18°N, 42.08°E and 180 m above sea level, is in Somalia's Gedo region (Wikidata).

The basin covers about 58,961 km², 81% of it in Ethiopia, lying between about 3.9° and 6.5°N and 38.0° and 42.1°E. It falls from 3,098 m in the north-west to 169 m at the outlet. The Awata, Digati and Mormora are its main tributaries (Wikipedia: Dawa River). Its names are Webiga Daawa in Somali, Laga Daawwaa in Oromo and Daua in Italian (Wikipedia: Dawa River).

Climate and water

The basin spans three climate zones: cool highlands, a temperate middle and hot lowlands. Ethiopian rainfall records for 1996–2016 show about 1,500 mm a year at the northern end, falling to about 200 mm near the outlet. The average temperature rises from about 15.5°C in the north to 28°C in the south (Wikipedia: Dawa River).

Groundwater is shaped by the rocks: water is freshest in volcanic areas and saltiest in sedimentary areas. In the dry south-east, people get water from flash floods after heavy rain and from shallow wells in dry river beds (Wikipedia: Dawa River; Environmental Earth Sciences, 2016; Environmental Monitoring and Assessment, 2016).

Plants, animals and herders

The biggest trees of the riverine forest grow along the lower Dawa, among them African ebony (Diospyros mespiliformis), sycamore fig, tamarind and African mahogany (Wikipedia: Dawa River). BirdLife International lists the Dawa–Wachile area of Ethiopia as an Important Bird Area (BirdLife: Dawa–Wachile IBA). Borana herders in the basin raise cattle and sheep because the long dry season makes crops hard to grow (Wikipedia: Dawa River).

When the river runs low, herders on all sides depend on the same water. The Danish Refugee Council reported on what happens to communities "when the river dries out" (Danish Refugee Council), and SIPRI studied climate and security in the Ethiopia–Kenya–Somalia border area (SIPRI, 2020).

Dams on the Ganale–Dawa system

Ethiopia opened the Genale Dawa III hydroelectric plant in February 2020 (Construction Review Online, Feb 2020).

Sources

• Wikipedia: Dawa River
• Wikidata Q1178464
• BirdLife International: Dawa–Wachile IBA
• SIPRI, climate-related security risks, 2020
• Danish Refugee Council