Abbay Basin

The Abbay Basin is a crucial river system in Ethiopia, responsible for 50% of the country’s total annual surface runoff while only covering 17.5% of its land area.
It provides water resources for various sectors such as agriculture, hydropower, and domestic use, making accurate measurement and management of river flow vital for their sustainability and effectiveness.
It is located in the centre-western part of Ethiopia, between latitude 7° 45’ and 12° 46’ N, and longitude 34°06’ and 40°00’ E (Fig.1).
The basin, also known as the Upper Blue Nile, covers an area of 199,800 km² within Ethiopia which also includes Dinder and Rehad sub-basins.
Elevations range from 475 m a.s.l. at the Sudanese border to 4,257 m a.s.l. at the summit of Mount Guna on the northern basin boundary.
The river, which originates at Lake Tana, accounts for approximately 55% of the annual renewable surface water resources of Ethiopia and accounts for 60% of the Nile flows reaching Egypt.