The Mereb River (), also known as the Gash River (), is a river flowing out of central Eritrea. Its chief importance is defining part of the boundary between Eritrea and Ethiopia, between the point where the Mai Ambassa enters the river at to the confluence of the Balasa with the Mereb at .Eritrea - Ethiopia Boundary Commission Decision Regarding Delimitation of the Border..., pp. 97, 102
Course According to the Statistical Abstract of Ethiopia for 1967/68, the Mereb River is long. The Ethiopian Ministry of Water Resources reports its Ethiopian catchment area as , with an annual runoff of 0.26 billion cubic meters."Water Sector Development Program (Vol.2)" Ministry of Water Resources (accessed 21 January 2009) Other sources talking about a catchment of to over all, and a discharge of in average over the year, and in peaks.ENVIRONMENTAL IMPACT ASSESSMENT KASSALA Its headwaters rise south-west of Asmara in central Eritrea. It flows south, bordering Ethiopia, then west through western Eritrea to reach the Sudanese plains near Kassala. Unlike the Setit or Takazze rivers, which flow out of Ethiopia and also forms a natural border with Eritrea, the waters of the Mereb do not usually reach the NileAdequacy of satellite derived rainfall data for stream flow modeling but dissipate in the sands of the eastern Sudanese plains, forming an inland delta.
The Mereb is dry for much of the year, but like the Takazze is subject to sudden floods during the rainy season; only the left bank of the upper course of the Mereb is in Ethiopian territory. Its main tributaries are the Obel River on the right bank (in Eritrea) and the Sarana, Balasa, Mai Shawesh, and 'Engweya Rivers on the left (in Ethiopia).
History The Mereb was important historically as the boundary between two separately governed regions in the area: the land of the Bahr negash (Tigrinya "kingdom of the sea", also known as Medri Bahri or "land of/by the sea") to the north of the river, and the Tigray to the south. The territories under the Bahr negash extended as far north as the Red Sea coast, and as far south (and west) as ShireDaniel Kendie, The Five Dimensions of the Eritrean Conflict 1941 – 2004: Deciphering the Geo-Political Puzzle (United States of America: Signature Book Printing, 2005), pp. 17–8. and the capital was at Debarwa in modern Eritrea, about south of Asmara.
Wildlife The river's Eritrean floodplain was the location of a 2001 sighting of a sizable elephant herd, the first such sighting in Eritrea since 1955.BBC Wildlife magazine, July 2003, retrieved at on 28 Sept 2007
See also List of rivers of Eritrea List of rivers of Ethiopia List of rivers of Sudan
References