Natural Flow Theory  Natural Flow Theory (NTF) is the concept that every riparian user (land touching the water) has a right to the water unaltered and undiminished [1] . Dams tend not to disrupt water flow directly, however water use and evaporation from the large reservoir upstream from the dam could reduce the flow of the Blue Nile. In turn, this could affect downstream countries. Evaporation from the Aswan dam in Ethiopia amounts to around 14 billion cubic metres [2] . The GERD will face similar problems, meaning that the downstream countries will have a reduced water flow. The reservoir will also become a tempting target for large agricultural businesses as well. These companies, many of them foreign, have taken part in ’land grabbing’ to secure water before for large irrigation projects [3] and could potentially tap in to the large reservoir. A similar example is the Colorado River, where dams and irrigation projects have reduced the flow of the river and impacted heavily on the river delta [4] . These threats to the Blue Nile’s river flow demonstrate the likelihood of decreased access to water in the downstream countries, violating the major principle of NTF.  [1] Smolen,M., Mittelstet,A. &amp; Harjo,B. ‘Whose Water is it anyway?’ Southern Region Water Program August 2012  [2] Consulate General of Ethiopia, Los Angeles ‘Grand Ethiopian Renaissance Dam’ data accessed 12/12/13  [3] Fisher,S. ‘Africa for Sale’ International Rivers September 2011  [4] Wikipedia ‘Colorado River’ date accessed 12/12/13