Streams and ravines
It
is one of the many joys of hiking Table Mountain to chance upon a burbling
stream, a secluded pool or a cascade pattering down on solid rock from up high.
The atmosphere that these features create acts as an effective medium through
which we connect with nature. Few sounds instil as much serenity as the trickle
of water on a mountainside or the clicking of frogs beside a backwater pool.
Add to that the geological drama and floral extravaganza on display on Table
Mountain, and you understand something of the mountain’s appeal.
Table Mountain’s waterways are in a constant state of fluctuation. Parched
streambeds in summer transform into gushing torrents in winter. Few perennial
streams occur on the mountain. Some of the ravines that carry water throughout
the year include Platteklip Gorge (lower reaches only), Disa Gorge, Window
Gorge and Skeleton Gorge. Even these often end up half-dry by late summer (February
/ March), their water reduced to an underground seep, only to burst into life
again in June at the onset of winter. Some hiking routes leading up ravines
become treacherous and nigh on impassable during the winter months, when sections
are transformed into foaming streams.
Skeleton Gorge is such a route; graded A (technically the easiest
grade), it feels more like a C-grade after a winter storm.
Mountains
are known to be the birthplace of rivers. Table Mountain with its flat
summit catches a lot of rain that drains down the many ravines dissecting the
mountain. The mountain’s proximity to the sea barely allows its streams to grow
into fully-fledged rivers. During the winter months, a single deluge can
transform a placid stream into a raging torrent. Runoff is fast and furious due
to the steep terrain, and there is little water retention; less so in summer,
when the mountain is parched and acts as a sponge. Hiking Table Mountain in
winter, one has the privilege of tracing streams right to their source, where
they start their journey to the sea as seeps near the summit. Hundreds of seeps
merge to form a stream, in turn joining other streams and swelling into torrents that thunder down the mountain.
I
often get asked about waterfalls on Table Mountain. These only really come into
being during winter, when Table Mountain receives 70% of its annual rainfall.
Well-known and conspicuous waterfalls include Hell’s Gates in Disa Gorge, the
cataract in Skeleton Gorge at its junction with the Contour Path, Blinkwater
waterfall, Grassy waterfall and Fountain waterfall, taking the names of the
ravines in which they occur. Grassy waterfall must rank as one of the longest and
strongest on the mountain, as it can easily be seen from a kilometer away,
appearing as a white ribbon on the eastern slopes. Located high
up the mountain in an inaccessible area, no one bothers to make the arduous
trek to its base. (Watch this space: I plan to make the trek this winter and
get some pictures)
A
detail often remarked on about Table Mountain’s water is its amber color. Streams
in the Western Cape are often referred to as blackwater streams, as the amber
color takes on a black appearance in deep pools. The color is caused by
chemical compounds, called polyphenols, leaching out from dead leaves. Plants
on Table Mountain produce polyphenols as defense against herbivores, as it
makes the leaves unpalatable. The presence of polyphenols only affects the
water’s color, not the taste. And it’s perfectly safe to drink. Some streams on
Table Mountain filters through clay soils, allowing the polyphenols to bond
chemically with the surfaces of the clay granules, ridding the water of its
amber hue. A good example is the Platteklip Stream, whose water emerges
crystal-clear at a point just above the Contour Path in Platteklip Gorge.
Which
brings us to the existence of subterranean streams on Table Mountain. I know of
three places on the mountain where water mysteriously emerges or disappears;
and no doubt more such places exist. One is the Platteklip Stream, mentioned
above, lifeblood of Cape Town up until the 1880s. Obvious along the
gorge’s lower reaches, the stream disappears a short distance above the Contour
Path, never to be seen again. Even in high winter, with water flowing down all
the ravines on the mountain, the middle and upper reaches of Platteklip Gorge
remain virtually waterless. In the Valley of Isolation on the Twelve Apostles, a small cave
allows one to see water flowing through
the mountain – east to west – its outflow still a mystery.
Another
unique aspect of Table Mountain’s water is its presence on the upper plateau
(the actual tabletop). For much of the year, large parts of the summit plateau
are waterlogged. The eastern table is known for its bogs, and even
features a lakelet, or small natural pool. About a meter deep during winter, it
gets topped up by the moisture-laden Tablecloth cloud-formation during the
long, dry summer months, when at times it dwindles to barely more than a marsh pit. As
for swimming possibilities, it’s too cold to enjoy in winter and too shallow in
summer, but fun and invigorating to wallow in on sultry spring days, when the
water level is fairly high.
Last
but not least are the springs of Table Mountain – those rare places where a
seep or drip can be found even in summer, when the mountain bakes under a
torrid sun and the heat shimmers off dust-dry watercourses. Several springs exist
on Table Mountain – and no one can profess to know the whereabouts of them all.
Back in the early days of mountaineering, hikers and climbers relied on springs
for their water supply. In the 1940s and 1950s, some were graced with small
ponds to pool the water for convenient drinking. Nowadays, hikers and climbers
carry their own water, only resorting to springs when their own supply run dry.
The
history of Cape Town and its people is entwined in the streams that flow off
Table Mountain. The city has the mountain to thank for its existence. As hikers
and climbers, we continue to draw sustenance from Table Mountain’s streams,
sometimes to quench a thirst or revive the body, but more often to drink in the
vitality and peace it brings to the surroundings.
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