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of which 45% is flood-irrigated, with a further 12,5% under microirrigation
(Anonymous, 1994)*. A new irrigation policy for South
Africa, which will assist in the optimum use of irrigation water, is
presently under discussion* * .
(vi) Much debate has centred on the timing of the ultimate water crisis
in South Africa as a whole, namely, when overall demand will
exceed overall supply (notwithstanding the impacts of droughts).
Before such a situation is reached however, a water quality crisis will
probably be evident, with insufficient freshwater available to dilute
industrial effluents and agricultural return flows. The Commission of
Enquiry into Water Matters (1970, quoted in Hattingh, 1979)***
suggested that the demand for water would outstrip the
economically available supply by the turn of the century. Du Plessis
and Van Robbroeck (1978, quoted in Hattingh, 1979) calculated that
the annual growth rate in water demand was not as high as the
estimated 7% bearing in mind technological supply and demand
innovations such as desalination, recycling and water restrictions.
Du Plessis and Van Robbroeck estimated the total volume of
economically available water at 34 x 10 9 m 3 y-1 (as opposed to the
27 - 29 x 10 9 m 3 y-1 assumed earlier). In their calculations, Du
Plessis and Van Robbroeck assumed that a consumption rate of
500 m 3 capita- 1 y-1 11 370 t capita- 1 day") was not unrealistic,
within the range 200 - 2 300 m 3 capita- 1 y-1 found in other
countries. Assuming such a consumption rate, the demand for water
will probably exceed the available supply around 2010 - based on an
approximately 2,2% increase in population each year - with a total
population of some 66 400 000 people by 2010. Other projections
can also be found in the literature and the ·cut-off" date is open to
speculation. However, what is certain, is that the water crisis will
strike in the first half of the next century. What is not clear is
whether the crisis will be one of affordabilitv (namely, financial
constraints on the importation of water from elsewhere in Africa); or
an absolute crisis (not enough water Jll!r g), or at best, insufficient
water in economically important regions. These issues are discussed
in Anonymous (1986 - above). (The findings and recommendations
of the Commission of Enquiry into Water Matters are reproduced in
Anonymous, 1986).
See Anonymous, 1994. SA op voorpunt met besproeiing, Agricultural News. 11 April 1994, p. 5.
See Backeberg, G.R., Bembridge, T.J., Bennie, A.T.P., Groenewald, J.A., Hammes, P.S., Pullen, R.A.
and Thompson, H., 1996. Policy proposal for irrigated agriculture in South Africa: discussion paper,
WRC Report No. KV 96/96, Water Research Commission, Pretoria, 119 p.
See Hatlingh, W.H.J.;1979. Suggestions for water research with regard to health aspects of potable
water, Symposium on Health Aspects of Water Supplies, National Institute for Water Research and
the Institute of Water Pollution Control {Southern African Branchl, 15 November 1979, Pretoria,
18 p.