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Summer
Rainfall 2008
A GOOD
SUMMER
Charts from
October 2007-March 2008: Dept of Water Affairs
http://www.dwaf.gov.za/Hydrology/Provincial%20Rain/Provincial%20Rainfall.htm
It was a very good
season for the interior provinces of South Africa, which
experienced above average and sometimes high rainfall
through the summer.
On the charts below,
the red
line shows this year's rainfall when we had several
weeks of 60-120 cubic metres a second in the Vaal. The
green
represents the great summer of 2005-6 when the river
peaked around 1800 cumecs and was seldom below about 400
(Jan-March), and the
blue
shows last year's disappointing rainfall when the river
seldom rose about 25 cumecs.
GAUTENG WAS TOPS
In 2007-8, the summer
just past, Gauteng in particular had lots of water, and
this fed into the Vaal system. Mpumalanga and North West
had similar rainfall patterns to those of the Free State
- above average. It was an extraordinary for the Western
Cape which had unseasonably high rainfall throughout the
summer. But KwaZulu-Natal did not fare so well and its
rainfall was on slightly above average in the early
months and then dropped to, at best, average. A
succession of cold fronts throughout summer explains
both the good interior rains and the exceptional
rainfall in the WCape. Even the Northern Cape, SA's
driest province, had rainfall well above average.
WINTER AND SPRING
TRIPS
-
There is a good
outlook for winter and spring water in the Vaal. We
will continue to run winter trips if the water level
warrants it, and will notify you if you are on the
Whitewater Watch List. Although Vaal Dam never
reached 100% (its highest level was just below 98%),
as this is written at the end of summer, the dam is
still at 96.8%. This bodes well for the coming
months, and especially August and September when
irrigation water is often released (if available)
for agriculture downstream of Parys. We can hope for
reasonable rafting water in the Spring. But
again, as this is written, the Vaal is approaching
its low level and has dropped overnight from a fair
25 cumecs to only 16 cumecs on 22 April.
NEXT SUMMER
As for next summer's
rain, all bets are off. After good rains in 2005-6,
which brought minor flooding to the Vaal in our area,
poor rains followed in 2006-7, with good rains again
this year. We have not had a real flood since 2000, so
if the ten-year cycle holds true, we could be in for one
soon - or maybe another drought year! Hold thumbs and
keep your paddles dripping...
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2008 RAINFALL FREE
STATE |
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2008 RAINFALL
GAUTENG |
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2008 RAINFALL
KWAZULU-NATAL |
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2008 RAINFALL
WESTERN CAPE |
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