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Sharing water in Australia:
a collaborative endeavour
James Cameron, CEO, National Water Commission, Australia
S
haring water between competing users continues to be
one of the world’s hallmark challenges of the twenty-first
century. This is no less true in Australia, the driest inhab-
ited continent on Earth.
Australia has a challenging hydrology. Highly variable and often
irregular rainfall and high rates of evaporation result in the lowest
run-off of inhabited continents. About 65 per cent of Australia’s
run-off is in the three drainage divisions located in the sparsely-
populated tropical north. Irrigated agriculture is concentrated in
the Murray-Darling Basin to the south-east where only 6.1 per cent
of national run-off occurs. The basin comprises about 14 per cent
of Australia’s land area, accounts for 65 per cent of Australia’s total
irrigated land and provides 39 per cent of the total Australian value
of agricultural commodities.
1
Most inland Australian rivers are naturally intermit-
tent and are unreliable water sources. The ratio between
the maximum and minimum annual flows in Australian
rivers is much higher than most major rivers across the
world. For the Yangtze in China, that ratio is two. For
the Darling River in Australia, the ratio is almost 5,000.
Groundwater usage also varies from region to region,
on average supplying around 30 per cent of total water
use in Australia. Consequently, Australia depends on
water storage more than any other developed country
and stores more water per head of population than
anywhere else in the world. Yet Australia has relatively
few sites for efficient dams. The Australian continent is
characterized by a lack of high mountains, and many
water storages are inefficient, shallow and wide.
T
ransboundary
W
ater
M
anagement
Irrigation of the Murray River
Image: courtesy of the Murray-Darling Basin Authority