Difference between revisions of "Diving the Cape Peninsula and False Bay/Alpha Reef"
Revision as of 13:53, 3 September 2009
The dive site Alpha Reef or Outer Spaniard Reef is an offshore rocky reef in the Pocklands Point area on the Cape Peninsula side of False Bay , 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.
It is a compact reef of medium depth and a pleasant dive, close to the slipway at Miller’s Point, but is not dived very often.
Names "Alpha Reef" and "Outer Spaniard"
The site was previously known as "Outer Spaniard", due to it's proximity to Spaniard Rock, but Alpha reef seems to now be more common usage.
S34°12.987’ E018°28.184’ (Highest point of reef)
This site is in a Marine Protected Area (2009)
Usually considered a boat dive 1.58km from Miller’s Point at 011° magnetic, but can be done as a shore dive from Rocklands Point. There is adequate parking on the gravel lay-bye on the seaward side of the main road M4, near the signpost warning against baboons. Access to the shore is poor. There are several steep eroded paths, some worse than others. Choose the one that looks best on the day. All are slippery and steep, with loose gravel. If you have a large group it may be worth arranging a rope for safety, otherwise a walking stick or staff could be useful. It is quite a long swim out to the reef. (about 420m).
See the site description for Spaniard rock for more information on shore access
The site is exposed to wind from all directions and waves from the south east and south west. The site will usually be at it's best in winter on days when the swell is low, but there are also occasional opportunities during the rest of the year. Conditions will probably be suitable if shore entry conditions are OK and there is no strong offshore wind. The return swim to shore could be a problem in a strong offshore wind (north west). If the south-easter is blowing there may be a slight current setting northwards, and the chop may make shore exit tricky.
Maximum depth is about 15m on the sand beyond the rocks. Average about 11m. Top of the reef at about 2m.
Granite of the late Pre-Cambrian Peninsula pluton
The reef is an outcrop of granite corestones in two main sections divided by an east/west gulley. The bigger southern outcrop is high, with the highest point within 2m of surface, sloping up from the south steeply at first, then more gradually to the top, then falling away nearly vertical to the bottom of the gulley. The north section starts from the gully and slopes gradually up to the north to about 4m above the sand, then drops quite steeply to the sand. Both sections slope down to the east, where the north section tapers down to nothing. The west end has a few outlying outcrops of various sizes. The south section is about twice the area of the north section and has a deep transverse crack just east of the high point. The reef extends approximately 160m from east to west and about 95m from north to south and is in a compact group, with few outliers. It has been reported (Zsilavecz 1998) that the reef continues inshore to Spaniard Rock, but there are some fairly large sandy gaps between rocks and it is not always possible to see from one to the next.
No site specific hazards have been reported. Offshore wind may increase in strength significantly during the dive, making a surface return swim difficult. The path is steep and slippery, specially after rain, and usually in poor repair.
No special skills are required for boat dives. The site is suitable for relatively inexperienced divers. Ability to navigate by compass, and reasonable fitness and agility are required for a shore dive.
(photographic equipment suggestions)
A compass is essential for shore dives to this site as there are sections where there are no reliable landmarks. A surface marker is recommended for warning boats of your presence during the long swim, and Nitrox may allow longer dive times without requiring decompression stops. It is theoretically possible to do the whole shore dive on Nitrox along the bottom, but carrying the required amount of gas down the hillside would be a major effort, never mind carrying the empty cylinders back up after the dive.
The reef has a zone of heavy red-bait at the top, with sparse Split fan kelp, and lower down is mostly covered by common feather stars with patches of Red chested and Mauve cucumbers, Striped anemones, and Strawberry anemones. The flatter deep sections have some fairly bare areas and quite a lot of urchins and black brittle stars. Also quite a few gorgonian sea fans in the deeper areas, many of which are partially or completely overgrown by other organisms.
Either swim out on the surface to the reef of go by boat. Position is most easily fixed by GPS. Dive round the reef. After you have seen the reef, either return to the boat or swim back to shore on a compass course. You may wish to visit Spaniard Rock on the way back
Views of the site from the shore.
Spaniard rock in the background seen from the road. The “path” starts in the foreground. Alpha reef is about in line with Spaniard Rock and about 250m further out.