Ethiopia’s Grand Renaissance Dam: Implications for Downstream Riparian Countries

AbstractEthiopia has begun seriously developing their significant hydropower potential by launching construction of the Grand Ethiopian Renaissance Dam (GERD) on the Blue Nile River to facilitate local and regional growth. The GERD, located just upstream of the border with Sudan, is the first dam ever to be constructed directly on the main stem of the Blue Nile and will become the largest dam in Africa. Although this has required substantial planning on Ethiopia’s part, no policy dictating the reservoir filling rate strategy has been publicly issued. This filling stage will have clear implications on downstream flows in Sudan and Egypt, complicated by evaporative losses, climate variability, and climate change. In this study, various filling policies and future climate states are simultaneously explored through a linked set of models (rainfall-runoff, routing, and hydropower) to infer potential streamflow reductions near Sudan’s Gezira Scheme, one of the largest irrigated areas in the world, and at Lake N...