Development of the Rating Curves for Egypt’s Water Resources Bank

Abstract

Water resources in Lake Nasser supply Egypt with about 97% of its freshwater needs. It is the water resources bank of Egypt. Estimating the amount of water in the storage reservoirs (lakes) from time to another is essential. The most straightforward and cheapest way is the rating curves. In the present chapter, the authors used the remote sensing and GIS along with the available water levels observations for the years 1992, 2000, 2006, 2009, and 2012 and the previously developed 3D profile of the lake to develop the rating curves for Lake Nasser. Lake Nasser is the water resources bank of Egypt and it supplies Egypt with about 97% of its freshwater needs. The estimated capacities using the present approach were compared with the those measured by the Aswan High Dam Authority (AHDA) and were found accurate enough with the root mean square error values ranging between 4–5% and 2–3% for volume/level relationship and surface area/level relationship, respectively, with underestimation of 2% for the entire period from 1992 to 2012. Consequently, the developed rating curves (and equations) could be used to estimate the water volume (capacity) of Lake Nasser instead of the costly measurements. However, field measurements by AHDA and NRI are needed to update such equations.