The Nile has apparently not changed course in 30 million years

How old is the Nile?

… It has been suggested that the Nile in its present path is ~6 million years old, whereas others argue that it may have formed much earlier in geological history. Here we present geological evidence and geodynamic model results that suggest that the Nile drainage has been stable for ~30 million years. We suggest that the Nile’s longevity in essentially the same path is sustained by the persistence of a stable topographic gradient, which in turn is controlled by deeper mantle processes. We propose that a large mantle convection cell beneath the Nile region has controlled topography over the last 30 million years, inducing uplift in the Ethiopian–Yemen Dome and subsidence in the Levant Sea and northern Egypt. We conclude that the drainage system of large rivers and their evolution over time can be sustained by a dynamic topographic gradient.

Apparently, an older Nile flowed through Libya, into the Sirte Rift (see image):

nile… we present geological and geophysical arguments supporting the idea that the Nile has been sustained by a mantle ‘conveyor belt’ operating through most of the Tertiary, with a convective upwelling centred under the Ethiopian highlands and a downwelling under the eastern Mediterranean, creating a topographic gradient that supported the Nile’s course over ~30 Myr. Such a course, which is similar to the present-day one, was likely established in the early Oligocene (30 Ma). Before that, our modelling shows that the drainage pattern was probably directed northwestward and controlled by the rifting process occurring in the Gulf of Sirte.

This indicates that at that time, rivers that drained into the Mediterranean Sea flowed farther to the west, possibly along the Sirte Rift that runs from northwest to southeast, which at that time was actively subsiding and being filled with a thick pile of sediments, indicating the activity of a large continental drainage…

Fascinating stuff. Read the whole paper here. (H/T Charles Onyango-Obbo)

As readers of the blog know, Nile waters are currently the subject of a diplomatic struggle between Ethiopia and Egypt. The US government recently offered to help negotiate a settlement. The parties involved set a January 15, 2020 deadline for negotiations. Stay tuned.

Egypt vs Ethiopia: Hydropolitics of the Nile Basin

I just finished reading John Waterbury’s The Nile Basin: National Determinants of Collective Action. The book offers a concise introduction to the politics of international water basins as well as the various points of contention among the riparian states in the wider Nile Basin.

Here’s an excerpt:

All upstream riparians in the Nile basin, including the Sudan share varying degrees of suspicion towards Egypt and Egyptian motives in seeking cooperative understandings. It seemingly follows that Ethiopia could mobilize these fears and occasional resentments into an alliance of upper basin riparians. The British in fact tried to do just that from 1959 to 1961, as Egypt and the Soviet Union jointly pursued the Aswan High Dam project at the expense of the upper basin (p. 86).

Why would upper basin riparians care about how Egypt uses water that flows up north?

As Waterbury explains, this is because of the international norm of Master Principle of appropriation — “whoever uses the water first thereby establishes a claim or right to it” (p. 28). Therefore, Egypt has an incentive to use as much of the Nile waters as possible in order to establish a future right to high volumes of downstream flows. Increasing domestic water consumption makes it easy for Cairo to demonstrate “appreciable harm” if any of the upper riparian states were to divert significant volumes of the Nile’s flows.

This is principle is in direct conflict with the principle of equitable use that also underpins riparian regimes (which are legion, apparently. Read the book). And that is where inter-state power politics come in.

Waterbury accurately predicted the current problem bothering Cairo:

The ultimate nightmare for Egypt would be if Ethiopia and the Sudan overcame their domestic obstacles to development and to examine coolly their shared interests in joint development of their shared watershed in the Blue Nile, Atbara, and Sobat basins. Given Ethiopian and Sudanese regional behavior in the 1990s, Egypt need not lose sleep yet (p. 149).

Well, it is time for Egypt to lose sleep. Big time.

A resurgent Ethiopia is damming the Abbay (Blue Nile) and is likely to divert more of its waters in the future for agricultural projects.

What’s puzzling to me is why Egypt is not interested in cutting a deal right now. Given that Ethiopia is only likely to get economically and militarily stronger with time, why wouldn’t Cairo want to cut a deal under conditions of a favorable balance of power?

An obvious explanation is that Egyptian domestic political concerns make it harder for the government to sign a deal that diminishes claims to the Nile (Sisi doesn’t want to be the one that signed away water rights!) But this problem will only get worse for Egyptian elites, assuming that Egypt will get more democratic with time.

I am not surprised that Ethiopia is playing hardball.