TITLE:
Mitigating the Impact of Climate Change by Reducing Evaporation Losses: Sediment Removal from the High Aswan Dam Reservoir
AUTHORS:
Emad Elba, Brigitte Urban, Bernd Ettmer, Dalia Farghaly
KEYWORDS:
Bathymetric Survey, Climate Change, DEM, Evaporation Losses, GIS, Sediments
JOURNAL NAME:
American Journal of Climate Change,
Vol.6 No.2,
May
4,
2017
ABSTRACT: Scientists in Egypt are particularly interested in the sustainable management of water and land resources. Global climate change will have a dramatic impact on the Egyptian water and land resources as well as its coastline and agriculture. Egypt is likely to become one of the most vulnerable countries in the world in the next several decades. Many climate scenarios predict that climate change will severely affect rainfall in the Nile basin and the flow of the Nile River in general and the High Aswan Dam Reservoir (HADR) in particular. Global warming and the higher temperatures will lead to higher evaporation rates, which, in turn, will result in less water availability at the HADR. Egypt’s Ministry of Water Resources and Irrigation predicts that the evaporation losses will, compared to the mean annual evaporation rates for the last 30 years, be approximately 3% to 10% higher by the year 2100. Since the construction of the High Aswan Dam fifty years ago, high sediment loads are a tremendous problem. 6.6 Billion Cubic Meter (km3) of sediments were deposited in the HADR during this period. The sediment has raised the lakebed level as well as the water level and caused a larger surface area. These developments have decreased the storage capacity of HADR and have increased the evaporation rate. The presented paper investigates the impact of lowering the lakebed by removing sediments from the HADR with a distinct emphasis on evaporation losses. A digital elevation model for the HADR was developed to describe the hydrological characteristics and to assess the consequences of removing sediment deposits. The results show that the removal of sediments will reduce evaporation losses by about 1.1 km3 projected for 2100, which represents 6.5% of the total projected evaporation losses.