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LONGITUDINAL SECTION OF THE FAYOUM

To those critics who suggest that the waters of the lake might become salted or leak into the Fayoum I have to reply as follows: When the old Lake Mœris, or the present Fayoum, was full of water and 63 metres higher than the bottom of the Wady Rayan, and remained so for thousands of years, there was no question of the waters having become salted or having escaped into the Wady. The Wady was as dry as it is to-day and the great inland sea was always fresh. If there had been any serious infiltration from the ancient Lake Mœris into the Wady Rayan, there would have resulted a lake which could not have escaped the notice of the numerous travellers who visited the lake. No mention was ever made of such a lake. This body of water moreover would have been inhabited by fresh-water animals whose remains would have strewn its shores. No such remains are to be seen to-day. If therefore the ancient Lake Mœris with a head of 63 metres on to the Wady Rayan could not leak into the Wady, it is not likely that the Wady Rayan reservoir with a head of from 27 to 29 metres on the Garak side of the Fayoum will leak into that part of the area covered by the ancient lake. Any leakage into the Lake Kurun side is never contemplated by anybody, since many kilometres of compact limestone lie between the Wady Rayan and it, while about one or two kilometres of the same limestone lie between the Wady Rayan and the Garak depression.

34. Lake Albert reservoir project and project for training the Albert Nile and the Zeraf River.

—If we wish not only to irrigate the whole of Egypt, but to include the Sudan in the sphere of operations we must regulate the supply issuing from Lake Albert Nyanza and ensure its passage through the great swamp regions. To my mind no work in the Sudd regions will be of any substantial value unless the Albert reservoir dam is first built. Tabulating the information collected in the gauges and discharge tables we may state that the discharge of the Albert Nile in cubic metres per second between the 15th January and 15th May was as follows in:—

1901190219031904
Discharge at Gondokoro6006007001000
Discharge above Sobat mouth300300350435

In 1861 the discharge at Gondokoro was as low as 500 cubic metres per second. It will be seen that, in spite of the great waste, there is an increase at the northern end of the Sudd region even under present conditions when the discharge at the south end is increased in the interval between the 15th January and 15th May. The water which enters the White Nile during these months represents the summer contingent of the White Nile to the Nile in Egypt.

Now though an increase in April at the south end of the Sudd region is felt at the north end, no such increase is felt in September and October, and the reason has been given in [Chapters II] and [III].

In April the Sobat river is discharging practically nothing, and the whole supply available in the Albert Nile can pass down the White Nile past the Sobat mouth. In September the Sobat river may be discharging 750 to 1,000 cubic metres per second, and as the White Nile cannot discharge the combined waters of the two rivers, the water of the Albert Nile is headed up and accumulated in the lowlands between Lake No and the Sobat mouth. This is greatly to the advantage of Egypt, for it is the discharge at the head of the White Nile between January 15 and May 15 which decides the White Nile contingent to the summer supply of the Nile in Egypt, and the greater the quantity of water above the head of the White Nile, in the absence of a regulator or barrage at Wadelai or Dufilé, the better the summer supply of Egypt. After the abnormally high flood of 1878, when Gordon was up the Nile, so great was the accumulation that the discharge at Assuân never fell below 1500 cubic metres per second in the summer of 1879. The Barrage was not regulated upon and yet all the Lower Egypt canals were full of water, and the cotton crop of Egypt for that year was quite abnormal for the seventies of the last century.