The discharge from Aswan onwards is estimated based on the discharge of the low years. As for the discharge during the period of low water in 1914.7 from the year, which was estimated by the Ministry of Public Works in its report for the year 1914, and the discharge during the period of low water in the two preceding years to 1914. The discharge was estimated based on the table of correlation between discharge and measurement, which was made from discharges taken by floats. And if it had not been for the fact that in the years 1914 and 1915, the riverbed was eroded, then the discharges during the low water periods would not have been entirely accurate. The estimated quantities are mostly based on the discharge during the flood.

(Table) Discharges in millions of cubic meters Numerical figures (1915-1916) Average 1914 (1915) 1915 (1916) 1916 (1917) 1917 (1918) 1918 (1919) Flood year was low... It is clear from these tables that the lowest total discharge in recent years is the discharge in the year 1918-1919, which was 14 million cubic meters, although the amount of water that passed through Aswan in each of the low years was about 15% more than this amount. The conditions have been prepared on the basis of considering the year 1915-1916 as an example of a low year that may occur frequently, and on the basis of the year 1918-1919, which is expected to occur. The water requirements are fully met. Referring to the table of average frequency, it is clear that this plan is safe in its consequences, because the revenue in the year 1915-1916 is completely insufficient to meet the demand, even if it could be distributed in a way that does not waste a single drop.

As for the preceding low years, it is impossible to meet the theoretical demands in full. The reason for this is that the silt-laden floodwaters cannot be stored. When the flood reaches its peak, the discharge, even in the low years, is more than the agricultural demand for the future. Therefore, there is no escape from losing some of the water by seepage into the sea. In addition, another amount of water must be lost by evaporation from the reservoirs held from the flood for use in the following summer. These inevitable losses from evaporation and seepage into the sea mean that the revenue in the year 1918 (whose total revenue was 14 million and the required amount was 15 million) is insufficient to meet the current demands, unless the loss in the dam area is prevented. If this loss is prevented and the maximum possible amount of floodwater is stored, it will be possible to meet the required demands in the year 1918, but no more. If a year with less revenue than that occurs, it will be necessary to meet all the necessary demands by storing a reserve from abundant floods and keeping it in reservoirs where evaporation losses are minimal.

It is evident from the foregoing that if the discharge during the flood in past years was of great importance, because of the great increase in the total annual revenue over the total annual demand, this will change in the future, and the amount of water discharged during the year will become more important, because the total demand in the low years will exceed the total revenue over the months of the year.

As for the usual years, thanks to the construction of reservoirs with sufficient capacity to store water from the flood season for use in the summer, the water revenue will be more than sufficient to meet all agricultural demands in both Egypt and Sudan.

The following chapters will explain in detail the proposed solutions to meet the urgent expansion needs in Egypt and Sudan, as well as the plans that are believed to provide a solution to the problem of meeting the ultimate future expansion needs in both countries.