Difference between revisions of "Diving the Cape Peninsula and False Bay/SATS General Botha"
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This article is a travel topic
The Dive site "SATS General Botha" also known as just the "G.B." is a deep historical wreck site in the central offshore area of False Bay, near Cape Town in the Western Cape province of South Africa.
This site is considered one of the more interesting wreck dives of False Bay, and the depth appeals to the more adventurous divers.
S34°13.679’ E018°38.290’ (Estimated midships)
Approximately 15.2km from Millers Point slipway bearing 113° magnetic. 19.8km from False Bay Yacht Club and 21.6km from Gordon’s Bay harbour.
This is NOT in a Marine Protected Area. A permit is not required.
The HMS Thames, an 1886 built River-Class cruiser (sister ship to the “Forth”, “Mersey” and “Severn”), was purchased from the Royal Navy by the philanthropist T.B. Davies in 1920 and donated to the South African Government as a training ship for seafarers. The vessel was renamed the South African Training Ship (SATS) General Botha, in memory of the first premier of the Union of South Africa, General Louis Botha, who had died in 1919.
The General Botha was scuttled by gunfire from the Scala Battery in Simon’s Town on 13th May 1947
Maximum depth is 54m on the sand, the top of the hull is at about 47m.
Topography and structure
The wreck lies on a sand bottom listing about 15° to port. The bow of the wreck faces approximately south west, with the centreline on an axis of approximately 236° magnetic. The hull is substantially intact from the ram bow to some metres abaft amidships, approximately level with the aft gun sponsons. Behind this the upper part of the structure is broken up and it is hard to see what is under the jumble of wreckage. The davits on the port side are still intact, and the tubular steel fore-mast lies on the sand to the port side at right angles to the hull just aft of the forward davits There is some sort of crosstree arrangement part way along the mast. The plating of the upper deck and upper topsides has wasted aft of the mast but the frames retain the shape of the vessel in this area (about a third of the length of the ship). There are small projections from the topside plating where the wing turrets were originally mounted. The bows are fairly intact and an impressive sight, with the stem sweeping down and forward towards the ram tip, which is at or below the level of the sand. The starboard side of the wreck forward of the collapsed area is in reasonable condition. The sponsons are clearly distinguishable and largely intact. Forward of the sponsons the upper deck is collapsed for an unreported distance, possibly all the way to the bow. There is a vertical cylindrical structure about central on the foredeck which may be supporting structure from the original forward gun mount. The hull plating on the side is partially wasted and there are large areas with lots of holes, and other areas where the plating is still closed. Near the sand there are areas of buckled plating which indicate that the wreck has probably subsided under its own weight as the structure was weakened by rusting. The conning tower (bridge superstructure) is missing altogether, as is the upper deck in this area, but there is a large roughly rectangular hole in the deck where it probably used to be. There are a number of built openings in the decks leading into the hull, and other openings resulting from corrosion of the plating.
Geology: The bottom of the bay is flat sand in this area
Low and short period swell is recommended, as the bottom time will be short and this is almost always a decompression dive. The trip to the site and back is also long and will be unconfortable in steep waves or strong wind.
This is an area which often has a significant variation in temperature between the surface and bottom waters, and sometimes a distinct thermocline
Keep a lookout for times when the sea is flat, the visibility is good and the wind is light. If the wind comes up during a dive, you just have to live with it, so check the forecast on the day.
Boat dive. This site is a similar distance from Simon’s Town, Gordon’s Bay, Kalk Bay or Miller’s Point, and it is a matter of convenience which is used.
A steel wreck of historical interest. The marine life is not particularly abundant on the wreck, but this allows a better view of the structure, which is quite spectacular if conditions are good.
This is a spectacular site in good visibility, which is not frequent. Wide angle for scenic shots, and powerful external lighting or strobes, as it is almost always quite dark. If you prefer macro photography, you will probably be better off at a shallower site.
No particular routes are recommended. The bow area is less broken up and better known. Much will depend on where the shot line is placed, as the wreck is large and your time will be limited.
Entrapment in wreckage, disorientation inside wreckage, Nitrogen narcosis, decompression sickness, surfacing out of sight of the boat, deteriorating weather and sea conditions.
Skills and competence appropriate to the depth and dive plan are recommended. Several divers have died at this site as a result of poor planning and inadequate equipment.
The depth of the site makes Trimix a preferable option. Nitrox and Oxygen decompression gases can significantly reduce decompression times. DSMBs or a Jersey upline are also strongly recommended in case the shot line can not be reached for ascent, and a light is also strongly recommended as it may be quite dark due to the depth. A dry suit is also recommended, particularly if much decompression is planned. It is considered prudent to use two boats for dives at this site, in case one has to leave early due to a problem, and to pick up divers surfacing away from the shotline. Penetration is not recommended, as the wreckage may be unstable.