Impacts of Constructing the Grand Ethiopian Renaissance Dam on the Nile River

Abstract

The Nile River (NR) is the primary water resource and the life artery for its downstream countries such as Egypt and Sudan. This chapter focuses on the impacts of constructing the Grand Ethiopian Renaissance Dam (GERD) on three main parts of the NR: close to Sudan-Ethiopia border; near Khartoum, Sudan; and the main Nile at the entrance of Lake Nasser, Egypt. The dam is designed to create a storage reservoir that will maintain a holding capacity of about 74 billion cubic meters of water at the full supply level. The impacts are divided into two main categories which are hydrological and environmental impacts. By studying the hydrological impacts, the study delineated the reservoir area to estimate the reservoir volume and its geometrical dimensions for all possible scenarios from starting the dam construction up to reaching the full operation and storage capacity. Results show that the best-accepted scenario for constructing the dam is by filling the dam reservoir with 10 BCM/year or less in 3.8 years. Furthermore, the impacts of the dam breach on Ethiopia and the downstream countries are studied via simulations from HEC-RAS model. In case of dam breach, a severe flood will result in inundation of the Sennar Dam, Sudan, 15 km wide and 200 km long, and the areas in between, until it reaches Khartoum, Sudan. Also, excessive water level with 3 m rise is expected from the dam until it reaches Nasser Lake. By studying the environmental impacts, particularly those of the population displacement, carbon dioxide emissions, agricultural lands, animals, and aquatic life, we will gain a better understanding of potential risks. This chapter discusses successes and many drawbacks of the GERD construction and its hydrological and environmental impacts on the Nile River downstream countries.