The Eastern Nile River basin

The Blue Nile River originates in the Ethiopian Highlands at Lake Tana. The river flows from Ethiopia into Sudan where it joins the White Nile at Khartoum to form the Main Nile. The Blue Nile is 1529 km in length with a catchment area of approximately 330,000 km2. The Eastern Nile River basin is composed of the Blue Nile, the Atbara, the Baro-Aboko-Sobat, the White Nile downstream from Malakal and the Main Nile sub-basins

Our work in the Nile started in 2008. The objectives were (1) to determine the operating policies of planned JMP reservoirs in Ethiopia and the re-operation of the High Aswan Dam and (2) to assess the economic benefits and costs associated with the Ethiopian reservoirs.

Then, in 2011, the Ethiopian government announced plans for the construction of the Grand Ethiopian Renaissance Dam (GERD) on the Blue Nile, east of its border with Sudan. We provided an independent analysis of the hydrologic and economic risks faced by downstream countries when the GERD would be online.

GERD on the Blue Nile

That study was latter extended to assess the economy-wide impacts by coupling our hydro-economic model with a CGE (computable general equilibrium) model of east Africa. This work was done in partnership with the Free University of Amsterdam (Prof. Roy Brouwer).

Water falls – Blue Nile River


  1. Goor, Q., R. Kelman and A. Tilmant, 2010.  Optimal multipurpose-multireservoir operation model with variable productivity of hydropower plants, Journal of Water Resources Planning and Management(ASCE), doi:10.1061/(ASCE)WR.1943-5452.0000117  
  2. Goor, Q., C. Halleux, Y. Mohamed and A. Tilmant, 2010.  Optimal operation of a multipurpose multireservoir system in the Eastern Nile river basin,  Hydrology and Earth System Sciences, 14, 1895-1908  
  3. Arjoon D, Y. Mohamed and A. Tilmant, 2014.  Hydro-economic Risk Assessment in the Eastern Nile River Basin. Water Resources and Economics. doi:10.1016/ j.wre.2014.10.004 
  4. Tilmant A., G. Marques and Y. Mohamed, 2014.  A dynamic water accounting framework based on marginal resource opportunity cost.  Hydrol. Earth Syst. Sci.,19, 1457-1467  
  5. Arjoon, D., A. Tilmant, and M. Herrmann, 2016. Sharing water and benefits in transboundary river basins, Hydrol. Earth Syst. Sci., 20, 2135-2150, doi:10.5194/hess-20-2135-2016
  6. Negash Kahsay T., D. Arjoon, O. Kuik, R. Brouwer, A. Tilmant, P. van der Zaag, 2019. A hybrid partial and general equilibrium modeling approach to assess the hydro-economic impacts of large dams – The case of the Grand Ethiopian Renaissance Dam in the Eastern Nile River basin. Environmental Modelling & Software 117: 76-88. DOI: 10.1016/j.envsoft.2019.03.007
  7. Tariku T. B., K. E. Gan, X. Tan, T. Y. Gan, H. Shi and A. Tilmant, 2021, Global warming impact to River Basin of Blue Nile and the optimum operation of its multi-reservoir system for hydropower production and irrigation, Science of Total Environment,
Schematization of the Eastern Nile River basin