Difference between revisions of "Diving the Cape Peninsula and False Bay/Kanobi's Wall"
Revision as of 12:18, 6 September 2009
The dive site Kanobi's Wall is an offshore rocky reef in the Karbonkelberg headland area on the Atlantic seaboard of the Cape Peninsula, near Cape Town in the Western Cape province of South Africa.
It is a good site for rugged topography, biodiversity and depth range.
This site can only be accessed by boat. It is about 6.9 km from Hout Bay harbour.
The blinder just south of the rock furthest off Duiker Point which extends above sea level.
This site is in a Marine Protected Area (2009). A permit is required.
This blinder off Duiker Point was named "Kanobi’s Wall" by Odette from Pisces Diving in 2005. It has been speculated that this may have some connection with the character Obi wan Kenobi in the Star Wars movies, but this has not been confirmed.
Maximum depth is about 25m, and the reef breaks the surface at one place.
Relief above 18m is quite spectacular. Huge stacked boulders, with tunnels, overhangs and caves of various sizes, and lots of vertical walls, some probably 10m or more in height. Deep narrow gaps and crevices. No sand seen. A knocking sound suggests a loose boulder somewhere, which is moved by the surge. There is a small cave at S34°02.358’ E018°18.103’, a low, wide cave at S34°02.347, E018°18.102’, 19m deep, and a swim-through from S34°02.349’ E018°18.116’, 13m deep to S34°02.358’ E018°18.125’, 13m deep.
Geology: Granite of the late Pre-Cambrian Peninsula pluton.
The site is exposed to westerly swells and wind, and also, though the fetch is relatively short, to south easterly winds and wind chop. The wind chop will not usually affect the diver when underwater, bur can make recovery by the boat relatively difficult, particularly if there is wind driven spray. South westerly swell will significantly affect diving due to surge conditions, as the site includes quite shallow areas and a number of narrow gullies and swim-throughs, which can focus and magnify the water movement to an awesome surge, and can provide some adrenalin rushes for the unwary diver. The site is usually at it's best in summer but there may also be occasional opportunities during autumn and early winter. Note that in summer the south east wind may pick up from a calm morning to strong or even gale force by afternoon. This is reasonably predictable and the weather forecast should be consulted.
This is an area which sometimes has upwellings, caused by the south easterly wind, resulting in cold, clear water, sometimes followed by a plankton bloom, which reduces the visibility again.
Keep a lookout for times when the forecast is for low short south westerly swell and light winds, as this will indicate a reasonable chance of good conditions.
Typical of the big reefs of the Atlantic coast. Heavy growth of red bait in shallow areas, Split-fan kelp on top surfaces of the reef in moderate depths. Walls, caves and overhangs are covered with a wide variety of sponges, corals, ascidians and other invertebrates.
Good site for photography if the surge is not too strong.
Drop in near the pinnacle and swim around the rocks at various depths. Start deep and work your way up, inspecting the various zones. It is necessary to keep away from the blinder when surfacing, as the surge over the top can be dangerous to both divers and boats, so it is advisable to swim well away during the ascent, and for this reason a DSMB and compass are recommended.
Cold water, Strong surge in gulleys and swim-throughs. Breaking waves over exposed rock. Sea urchins. Strong offshore winds may develop over a short time.
Ability to deploy a DSMB is useful, as is ability to use a compass. Divers should be adequately skilled at buoyancy control in surge, and able to fin fairly strongly, unless the swell is exceptionally weak.
Take a light to see into dark places, like overhangs and swim-throughs. A compass is useful to keep track of where you are, and a DSMB is useful if you surface away from the reef, which is desirable as the waves break over the blinder. Nitrox may extend your dive time if you are well insulated.