botswana/namibia - Cour international de Justice

331. The Chobe is a perennial mature river with stable, non-erodible and readily discernible
banks. In the vicinity of Kasikili/Sedudu Island both banks of the northern channel are readily
discernible, at all seasons of the year, and in particular when the island is inundated in the wet
season (paragraphs 365 to 367 below): see the aerial photographs May 1972 and May 1997,
photographs taken in May and August 1997, and the satellite imageries of June 1975, March
1995 and June 1996. The aerial photography in the preparation of the South African JARIC
map was used as the basis for the July 1977 image (at page 125). (See also para.69 of
Professor Sefe's Second Opinion).
(v) There is an absence of zones of sedimentation in the northern channel
332. The absence of zones of sedimentation and the absence of any evidence of erosion again
support the stable profile of the northern channel as the main channel (paragraphs 368 to 375
below).
333. Sediment bars located at the bifurcation point in the northern and southern channel and
on the right of the southern channel in the big meander loop are permanent features of a low
energy river. They are relict bars of earlier downstream flowing channels, not active zones of
sedimentation. The absence of any such bars in the northern channel indicates strength of flow
(paragraphs 377 to 378 below).
(vi) The Chobe is a river with continuous flow
334. Flow in a downstream direction through the northern and western channel is continuous
with a constant level of 925.6 metres, South African Mean Sea Level,measured at the Kasane
Gauging Station through all seasons of the year (paragraphs 378 to 381 below).
(D) It is irrelevant to the determination of the northern channel as the main channel
whether one or two channels exist in the Chobe River
G15 - July 1997 image (The JARIC aerial photograph), Figure 13, Sefe, 2nd Opinion
335. Regardless of the existence of one or two channels, there can be no question that the
northern channel is the sole, and hence the main, channel of the Chobe River.
336. In fact according to the German version of Article III of the Anglo-German Agreement
of 1890 which refers to the Thalweg des Hauptlaufes, it is immaterial whether the river flows
through a single or multiple channels because the application of the thalweg will always
indicate a single channel. The Namibian Memorial is clearly very much aware that the
determination of the thalweg will totally defeat its arguments in favour of the southern
channel. Hence it exhorts the Court to search first for 'the Hauptlauf'3.
[3. Namibia exhorts the Court as follows: "The main channel must be found first. The centre can necessarily only
be found afterward. This point is equally pertinent, to the German translation of the formula ... in Thalweg des
Haupt laufes ... In the same way as with the English text, the search must be for the 'Hauptlauf' and for the
'Thalweg' only after the 'Hauptlauf' has been found. The 'Hauptlauf' cannot be identified by first seeking to find
the 'Thalweg' (emphasis added). (Namibian Memorial, p.44,para. 117).]
337. The thalweg is defined as 'the line of maximum depth along a river channel'.