Taking the Nile problem to science

June 25, 2013

Following a recent completion of a study by an international panel of experts regarding the impact of the Grand Ethiopian Renaissance Dam (GERD) on the flow of the Nile, various analyses have been published over the last few weeks. These analyses have come from various perspectives, including scientific, engineering, legal, economic, and political frameworks.

One of the analyses emerged from a newly formed Group of the Nile Basin (GNB) by 12 professors from Cairo University, Egypt. The stated objectives of the GNB include analytical studies of the Ethiopian dams (the GERD and three other planned dams), preparing numerical water models to study the side effects of these dams, and collecting recent scientific studies in the field.

To the extent that scientific analyses inform policy decisions, the initiative taken by the GNB to analyze the Nile Problem from a scientific framework should be welcome as a step in the right direction. The GNB has presented its assessment of the impact even though whether its reported findings and recommendations will solve the problem through scientific approaches may be questionable.

By focusing specifically on some thematic comments presented by the GNB, the following analysis attempts to independently look at some of the issues it presented and invites continued analysis of the Nile Problem within the realm of science. This analysis is limited to some publicly available data and attempts to dispel some of the misconceptions of definitions of certain terms in water resources, which often become grounds for water right claims by political entities.

Various analyses appear to use the terms Basin States and Riparian States interchangeably, which could easily confuse the layperson. While the two terms are different, the word Basin may be easier to understand than Riparian. Going to the origin of the word Riparian and applying it to the Nile using quantitative data may help clarify their differences and dispel some misconceptions.

According to some sources, the term Riparian comes from the Latin word Ripa, which means river bank.

In California where riparian rights are in effect for pre-1914 water uses, this right is for continued beneficial water uses for physically riparian lands. In this case, a riparian land is defined as the smallest parcel physically abutting a watercourse. Claimed riparian rights for beneficial uses are generally for a rather small fraction of the flow in the river.

The Nile is estimated to be about 6,700 kilometers long. Evidently, the length of the Blue Nile in Ethiopia, Sudan, and its segment downstream from its confluence with the White Nile to the Mediterranean Sea is significantly shorter.

Using conservative estimates that the smallest parcel abutting the Nile is half a kilometer wide on each bank of the Nile and that there is a continuum of parcels along it for which water diversions are needed for beneficial uses, the total riparian area along the course of the Nile in which the Blue Nile flows cannot be more than 6,700 square kilometers.

The Nile Basin, also known as catchment area, is estimated to be about 3 million square kilometers, which is roughly about one tenth of the area of Africa.

According to the above conservative estimates, the riparian land of the Blue Nile may well be less than one percent of the Nile Basin.

Then, for the sake of argument, if the people in the Nile Basin invented a rain harvesting mechanism and were to do that on their parcels, Nile’s riparian parcels may have to endure major water stresses. However, reality is not argument and arguments may not be winnable amicably.

Nature has made the Nile Problem such that: 1) rain falls more intensely in a certain sub-region of the Basin, 2) natural conveyances in the form of rivers transport its runoff to certain regions of the world where some of the earliest human civilizations thrived, and 3) a diverse group of population is widely spread throughout the Basin and growing in large numbers.

The Nile Problem, which isn’t unique, is one of relatively stationary average water supply and growing water demand. This problem can be illustrated as shown below using the populations of Egypt and Ethiopia along with the flow of the Nile. While the supply data that may have been used half a century ago for exclusive treaties may still be generally relevant even if the data in the early period of measurement may be less dependable, there is an evident dynamics of continued growth in water demand.

The graphs suggest that due to the increasing water demands and relatively stationary average water supply in the Nile Basin, a cooperative framework is indispensible. This situation avails not only a problem but also opportunities whereby interstate cooperation may lead to optimal planning and management of the Nile Basin’s water resources. If the scientists in the region make concerted efforts towards this end, optimal uses of these resources for the benefit of those in the Basin are likely to manifest in the coming years.

The Nile Problem: The graphs at the top show historical and projected populations of Egypt and Ethiopia, according to United Nations and other estimates. The graphs in the bottom panel show estimated historical natural annual flows of the Nile at Aswan High Dam according to Hipel and McLeod (1994), its estimated historical climatological period moving average, and projected climatological period average. The World Meteorological Organization defines a climatological period as 30 years.

The writer can be reached at MZEjeta at aol.com