Diving the Cape Peninsula and False Bay/Vulcan Rock
The dive site Vulcan Rock is reef in the outer Hout Bay area on the Atlantic seaboard of the Cape Peninsula, near Cape Town in the Western Cape province of South Africa. Information is provided which may assist in planning Recreational and Research Scuba diving at this site, and links to photographs of marine organisms that have been found there.
Vulcan rock is the highest point of a large granite reef and breaks the surface at some states of the tide. It is low and flat on top and big enough to park a car. If there are extensive whitecaps it may be difficult to see from a distance, so it can be tricky to find on a day with low swell and a strong South easterly wind unless you have GPS. A spectacular dive if the visibility is good.
Name "Vulcan Rock"
The rock marking the site is shown on charts of the area as Vulcan Rock.
This site is in a Marine Protected Area (2009)
The site is acessible only by boat. it is about 5.5km from Hout Bay Harbour. Anchoring is possible, but the bottom is very rugged and anchors often foul.
The site is exposed to south westerly swells, which can cause a strong surge. The site is usually at it's best in summer but there are also occasional opportunities in autumn and winter.
This is an area which sometimes has upwellings, caused by strong south easterly winds, resulting in cold clear water, which may develop a plankton bloom over a few days, which will reduce the visibility again.
Keep a lookout for times when the south west swell is low and short period, and there is not too much south easterly wind forecast.
Maximum depth is over 30m but this is some way to the north of the rock.
Granite of the late Pre-Cambrian Peninsula pluton
Vulcan rock is the top of a very big granite tor. It is made up of large corestones on top of more of the same, down to at least 25m or so. There are lots of crevices, overhangs and fairly narrow gaps. Boulders are often several metres high. There is usually a knocking sound as loose boulders are rocked by the swell.
Cold water, Strong surge in cracks and swim-throughs. Sea urchins. Strong offshore winds may develop over a short time, making it tricky to spot divers on the surface, and a wet trip back.
No special skills required.
Good site for photography, specially close-up shots of invertebrates.
The site is cold and relatively deep, and a dry suit is recommended. This is a dive site where the use of Nitrox can be worthwhile to extend no-stop time. A reel with DSMB, Light and Compass are also recommended.
Heavy growth of red bait in shallower parts, Some kelp, probably mostly Split-fan kelp, Heavy encrustation of sponges, sea fans, bryozoans and colonial hydroids on steep faces, and particularly under overhangs. Flatter rock surfaces in deep areas are often covered by urchins and grey cucumbers.
Choose a route to suit your desired profile. For greater depth go north past the north pinnacles which do not break the surface. There is a large swim-through near the pinnacle. at about ??m depth