WATER FOR SUDAN

Evening Star, Issue 22195, 25 November 1935, Page 9

WATER FOR SUDAN

LAKE TSANA AND THE BLUE NILE Through the 8.8. C. the public •were told recently (I quote from ‘ The Listener’) that: “It is a vital British interest that there shall bo no interference that will prevent the waters of Lake Tsana continuing the work of irrigation on which the very existence of the Sudan and Egypt depends,” writes Major-general Sir Charles Gwynne in the 1 Morning Post.’ It is, of course, true that the Sudan and Egypt depend on irrigation, but it is not true that the lake materially affects irrigation works now in existence, or that, it can affect the extension of those works to a “ vital ” degree. • It would merely affect the somewhat problematical extension of the area under cotton cultivation in the Sudan.

The project was first investigated in the report published in 1904 by Sir William Garstm on the Nile, which still in essential holds good, though the development of the Sudan since that date has somewhat increased the importance of the project, then placed in a secondary category. The material point to my mind is that no interference with the execution of the project can take place without damaging the interfere!- quite as much as the country the scheme is designed to benefit. Consider the physical conditions. The lake lies in a basin forming a remarkably small catchment area, and the rim of the basin rises some- 1,500 ft above the level of the Jake, except where it is broken through by the Blue Nile. That river forms the only practicable means of drawing off tbo waters of the lake, and it immediately plunges into a deop, inaccessible, and totally uncultivable ravine, from which it does not emerge till it reaches the Sudan frontier. It is evident, therefore, that it is quite impracticable to tap the waters of the lake by another channel or divert them from reaching the Sudan. Sir William Garstin’s report mentions as a possibility driving a tunnel to bring the Jake water to the Rahad and Dinder Rivers, tributaries joining the right bank of the Blue Nile in the Sudan. These rivers, which cease to flow in the dry seasons, pass through an area of the Sudan suitable for cotton cultivation. The idea was negatived _as impossibly expensive, and any similar > project to divert waters east to Italian or Abyssinian territory would be infinitely more difficult. Interference is, in fact, limited to the denial of permission to construct control works, which would benefit the Sudan, at the exits of the lake.

This interference has up till a few mouths ago_ actually been exercised by the Abyssinian Government chiefly owing to a suspicion that communications opened from the Sudan to the lake in connection with the construction of works would lead to a measure of foreign control, locally, and would prove n dansrer in event of war Such suspicions have cost Abyssinia large sums which would have been paid for labour and whatever royalties might have been charged for water delivered through the barrage. It must be evident that if Italy were in control in Abyssinia she would be unlikely to neglect such an easy source of _ income. At the worst, therefore, Britain can be barred only from improving existing conditions. There is no question of their being worsened. The control of the lake affects only the dry season flow of the Nile, which may he artificially increased, but cannot bo deminished.

As regards the silt-laden flood water which reaches Egypt from Abyssinia, it is evident that it comes from a much greater area than the Lake Tsana

basin; from south to north it reaches the main course of the Nile by three avenues—the Sobat River, the Blub Nile, and the Atbara River. The first and last of these make practically no contribution to the Nile in the dry season, but carry great volumes of water when in flood.

The Blue Nile falls very low in the dry season, but both when low and when in flood it is maintained not merely-by the Lake Tsana catchment, but by numerous perennial streams and rivers which join it after it leaves the Jake, some (like the Didessa) of considerable size. The area they drain is much greater than the lake basin. Np one, of course, can interfere with the run-off of flood water, for Mussolini himself could _ not check the rainfall which causes it. Si? far as British interests are concerned, therefore, Egypt is not affected ; she retains the visitation of flood water, and it is on the White Nile she depends _ for the further development of her irrigation projects, and for water of her cotton crops at season of low Nile. The Sudan m the future might derive benefit from Lake Tsana, but Italy would have even less reason for interfering with that project than has Abyssinia. The only possible use she could make of the lake would be in connection with hydro-electric undertakings, which,, though they would not divert water, might affect the regulation of its delivery at suitable seasons.