Geology -- Egypt; Nile River; Water-supply -- Egypt
“If this project, or any other project of any kind, is ever to be
carried out on the upper waters of the White Nile, the very first thing
to be done will be to construct a weir or barrage at the outlet of the
Albert Lake, at Wadelai, or lower down at Dufile. I should say, judging
from the map and the cross section, that Wadelai itself would be an
excellent site for a weir. I have advocated this project in season and
out of season these ten years, and now that actual discharges and
figures are before me I am more than ever convinced that I was no untrue
prophet when I wrote in my book on “The Assuân Reservoir Dam and After”
that “the point where Lake Albert ends and the Albert Nile begins to
have a rapid and contracted stream will be the site of the future great
regulator or barrage of the upper waters of the Nile. This work will be
here or at Dufile.” Such a work would cost anything between £400,000 and
£1,000,000.
“If such a work were carried out it would be possible to insure every
year a discharge of between 1,000 and 1,500 cubic metres per second at
Gondokoro from the 15th of January to the 15th of May, _i.e._, during
the months which determine the summer water supply of the White Nile for
Egypt. Such a quantity of water would insure 435 cubic metres per second
at the head of the White Nile, as it has done this year, even under
existing conditions; while with training and dredger work in the Albert
Nile and Bahr Zeraf between Gondokoro and Lake No, it might be increased
to 600 cubic metres per second, and even more. The way in which this
work of training should be carried out has been admirably laid down on
page 174 of Sir William’s Report”.
There are moreover other reasons I think for condemning the excavation
of a straight cut 340 kilometres in length across the eastern corner of
the Sudd regions. The reasons are to be found in Sir William Garstin’s
Report itself. One of the most interesting features of this report is
the number of actually measured discharges at different sites. Of all
these sites Gondokoro, the southern key of the Sudd region, is the most
interesting.
It is very evident from an examination of Sections Nos. 18, 19, 26 and
27, Plate VIII of Sir William’s Report, that the Albert Nile at
Gondokoro scours out its bed very severely after a high flood like that
of 1903. The width of the section is about 230 metres with vertical
sides, and yet while a gauge of ·50 metres on the 1st April 1903 (after
the low year of 1902) gave a section of 615 square metres; on the 9th
September 1903 (after a good year), the section was 1,347 square metres
for a gauge of 2.33 metres. In other words, a rise of 1.83 metres gave
an increased section of 732 square metres; while, if the bed had not
scoured, it would have been 421 square metres. We have here an increase
of 311 square metres, or more than 1 metre of scour. All this happened
in 5 months, and proves that the clear water of the lakes, when in
volume, has a fine cutting edge.
Public-domain text, read in full here on John Shaqi.
Reviews
Reviews
No reviews yet
Be the first to share your thoughts on this work.
Elsewhere in the archive
Join the Discussion
Join the discussion
Sign in to leave a comment or review.
Sign InorCreate an account