6. South Africa-Catchment-Context
6.1.
The Sand River Catchment
This section introduces the Sand River Catchment, the focus area for WHiRL research
in South Africa.
6.1.1. Background
The Sand river is part of the Sabie-Sand system, a transboundary river system rising
in South Africa before passing through Mozambique. Figure 6.1.1 shows a map of
the Sand – with insets of the larger Sabie-Sand system, as well as the approximate
location of the Sand within South Africa.
SAND
SUB-CATCHMEN T
K
A
C
O
E
N
SABIE-SAND
CATCHMENT
AD
dl
an
Nw
Klein San d Ri ver
Thulandzite ka
MANYELETI
GAME
RESERVE
Se
ph
i ri
ACORNHOEK
ari
uh
am
CD
ED
Sand River
OD
THULAMAHASHE
Mohlomobe
Mutlum uvi
DRAKENSBERGMOUNTAINS
Nwarhele
SA
BIE-SAND
GAM
ERESERVE
Sand River
K
N
BUSHBUCKRIDGE
0
10
20
km
Figure 1 The SandRiver sub-catchment, indicating the catchment boundar y, major rivers, existing dams and gam e reserve boun
The catchment, which has an area of approximately two thousand square kilometres,
contains three distinct sub-regions. Rising in the Drakensberg mountains to the West,
in an area of high rainfall (2000mm per year), it quickly descends to a densely
populated mid section, before finally flowing through a sparsely populated and dry
(550 mm rainfall), but ecologically important, lower section before finally joining the
Sabie river within the Kruger national park.
On its journey the Sand is a critical resource to a wide range of stakeholder groups
including: commercial forestry plantations (~5,000ha) in the western highlands,
domestic and irrigation users (~3,000ha) in the mid-section, and wildlife and (limited)
in the lower catchment. The water that reaches the Kruger park plays an important
part in ensuing the ecological functioning of the riverine ecosystem both within and
outside the park.
6.1.2. Water management issues
The population of the middle ranges of the Sand is of the order of 300,000 at the
present, but is expected to grow rapidly. In addition, a further 75,000 people living
outside the physical boundaries of the catchment rely on water drawn from within it.
These people are currently chronically under-served in water supply services, with at
least 30% failing to reach the minimum standard of 25 lpcd.
At the start of the project it was already clear that the surface water resources of the
catchment were already heavily used, with strong reason to feel that they might
already be over committed. The estimated median annual flow generated by the
catchment in its ‘natural’ condition is 75 Mm3/yr, but typically of a system in this
region the flows are concentrated in the wet-season months, and inter annual
variability is very high (the average flow, skewed by extreme flood events, is
136Mm3/yr). As a result of this natural variability, limited and poorly managed
storage, and un-controlled irrigation abstraction, the flow of the river is frequently
completely cut during the dry-season months.
6.1.3. Save-the-Sand Integrated Catchment Management pilot project
With a growing potential for disagreement – and potential conflict – over water
resources between up and downstream users, and the challenge of providing
appropriate water services to its population, the Sand makes an excellent case study of
many of the pressing water resource related problems facing South Africa as a whole.
Partly because of this, the Sand was selected by DWAF, in collaboration with the
Department of Agriculture (DA), as a pilot project for the design and implementation
of an Integrated Catchment Management Plan. This project, named the Save the Sand
Project, provided the larger framework within which the WHiRL project work took
place.
Read more
Pollard, S. and Walker, P. 2000. Catchment management and water supply and
sanitation in the Sand River Catchment, South Africa: description and issues.
WHIRL Project Working Paper 1. NRI, Chatham.
Other references and links