South Africa's coastal waters can be divided into a number of biogeographical regions, though there is generally not a sharp distinction between them where the boundaries have been placed. There is more of a gradual change along the coast, from the tropical waters of northern KwaZulu-Natal to the cooler waters of the south coast.

The one place where there is a relatively distinct change over a short distance, is at Cape Point, where the waters of the east and west sides of the Cape Peninsula support noticeably different ecologies, and even here there is a significant overlap of resident organisms.

There are a large proportion of endemic species along this coastline, particularly along the South Coast.

The marine ecoregions

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The regions of interest to recreational divers are the coastal ecoregions, which are accessible and shallow enough to dive. These are considered to extend from the shoreline to the break of the continental shelf, so most of the area is far too deep to dive.

• The cool temperate Benguela ecoregion extends from Sylvia Hill in Namibia to Cape Point. The cold Benguela Current is the major influence, and the region is characterized by large-scale intensive upwelling and nutrient rich water. At the south eastern end of this region, the break at Cape Point is very distinct in the inshore depth ranges, but in deeper areas it has been chosen as the depth contour at of 150 m, to approximately south of Cape Agulhas. This line is more consistent with the mixing zone of the Benguela and Agulhas currents, and is roughly parallel to the shelf edge.
• The warm temperate Agulhas ecoregion extends from Cape Point to the Mbashe River. The Mbashe River was chosen as the most appropriate boundary between the subtropical Natal province to the north, and the warm temperate Agulhas region to the south, but change is gradual between these regions. Upwelling on the south coast of South Africa is largely driven by the Agulhas current and the continental shelf. This form of upwelling forces cold deep water up onto the continental shelf, but not necessarily above the thermocline. In the region east of the Agulhas bank, wind enhanced upwelling, occurring mainly in summer, augments the current driven upwelling bringing the colder deeper waters to the surface. This enhances biological productivity by supply of nutrients to the euphotic zone (where plants have sufficient light to flourish) which fuels phytoplankton production, and rocky shores that are supplied with the nutrient rich water support rich algal biomass. The annual chokka (squid) spawning takes place largely in this region.
• The subtropical Natal ecoregion extends from the Mbashe River to Cape Vidal. This area has high riverine input, but the Agulhas Current is the major influence on the Natal ecoregion. Reef habitat is limited and the major reef areas include Aliwal Shoal and Protea Banks. The rocky reef communities are distinct from the coral reef communities further north as stony corals decline with increased turbidity to the south. The Natal ecoregion supports endemic soft corals. The annual sardine run is a feature of the southern portion of this region.
• The tropical Delagoa ecoregion extends from Cape Vidal northwards into Mozambique. A clear change in marine community structure at Cape Vidal is indicated by the intertidal habitat, seagrass and mangrove distribution patterns, and tropical seabird and cetacean species ranges.

Ordinary recreational scuba diving equipment is sufficient for most dive sites in most of the regions. The largest variation in requirements being for exposure suits. In the tropical north-east, where water temperature is usually at or above 24°C, wet suits are worn as much for protection from the sun and stings as for warmth, while on the west coast a 7 mm wet-suit is barely sufficient, and dry suits are becoming more popular with divers who enjoy being comfortable at the end of a dive in water temperatures as low as 8°C. Most dive sites are relatively shallow — few are deeper than 40 m, and the majority are in the 10 to 30 m range.

There is no legal requirement in South Africa for certification as a recreational diver. You are legally allowed to buy equipment and dive with it with no training, certification, experience or competence whatsoever. There is also no legal constraint preventing you from going to sea and jumping over the side of the boat of your own free will wearing only a weightbelt, but there are more comfortable and convenient ways to kill yourself.

Most, if not necessarily all, of the dive charter operators will insist that you are certified to dive to the depth and in the conditions expected at the dive site, or are accompanied by a certified instructor. This is not only because they are concerned for your safety, but also it cuts down on the paperwork if there is an accident. It is bad for business to have your clients die during an outing, so most operators are fairly diligent in ensuring that clients are informed of the probable conditions and site specific risks and the recommended level of certification. Waivers are required in most cases, and the diver assumes responsibility for his or her own actions, and unless there is strong evidence of negligence or illegal actions on the part of the operator, litigation after the event is unlikely to make the dependants wealthy.

Some operators will cancel a dive if the conditions look like they will be unpleasant, and probably all will cancel if the conditions look dangerous. However, this does not mean that the conditions will necessarily be safe for you if the dive is on. You are expected to judge for yourself what you can handle, and whether the situation will be within your capabilities on the day, and make your own decision. The crew can advise, but cannot think for you.

If you are a trainee on a certification programme, you have the right to expect the instructor to advise you on risk and safety, but unless you have no certification at all you are expected to be able to make a reasonable and responsible choice for yourself.

The Western Cape province is the most south western province in South Africa. It includes a large proportion of South Africa's tourist destinations and attractions, amongst which are several of the better known diving destinations.

Cape Town

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Main topic: Diving the Cape Peninsula and False Bay

-33.93318.4676 Cape Town is a major port city and the legislative capital of South Africa. The waters of Cape Town include the Atlantic seaboard, on the west of the Cape Peninsula which is cool to cold temperate, and False Bay, which is also cool temperate, but significantly influenced by the warmer waters brought down the east coast by the Mozambique current and the Agulhas current, and has some ecological similarity to the south coast.

Cape Point is accepted as the boundary between the cool temperate Benguela ecoregion of the west coast, and the warm temperate Agulhas ecoregion of the south coast. Unlike the other boundaries between the marine bioregions, which are diffuse, the ecosystems vary quite distinctively over a short distance at Cape Point, due to the change from the dominating influence of the warmer Agulhas current to the east to the cold Benguela current to the west.

There are many endemic species of fish, invertebrates and seaweeds, as well as a variety of other more widely distributed organisms, and a large number of shipwrecks, some of which are highly regarded as dive sites. False Bay is sometimes host to wandering fish from warmer regions, and occasionally even turtles, brought in on the currents from the east coast.

The mountainous Cape Peninsula, which separates the Atlantic Ocean from False Bay, also protects the coastal waters on each side from wind and waves from the other side, making it possible to have year round diving, but seasonal variations in where to dive and what to see, as there is a significant and noticeable difference between the ecosystems on the alternative shorelines.

There are three marine protected areas associated with the coastal waters of Cape Town: The Table Mountain National Park Marine Protected Area which includes most of the reef dives and a large number of the wrecks, the Robben Island Marine Protected Area, with mostly wrecks, but not so many and some quite deep, and the small Helderberg Marine Protected Area, with very few dive sites.

Gansbaai

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See also: Diving the west coast of South Africa#Gansbaai

-34.583319.333310 Gansbaai is a small harbour town in the Overberg district of the Western Cape, well known for cage diving with great white sharks, and the wreck of HMS Birkenhead.

The Eastern Cape is a province on the south coast of South Africa on the coast of the eastern part of the Agulhas ecoregion, which is rich in endemic marine species. Diving is very dependent on weather conditions, and visibility is mot often good, but when it is good there is a lot to see. The water is generally warmer than the Western Cape, but there are occasional cold upwellings.

Tsitsikamma

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Main topic: Diving the Tsitsikamma

-34.02258323.898816 The Tsitsikamma National Park Marine Protected Area extends along the western part of the Eastern Cape coast and a small part of the Western Cape coast on the Garden Route.

Port Elizabeth

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Main topic: Diving in Port Elizabeth

-33.96725.619 Port Elizabeth is a major port city in the Eastern Cape on the shores of Algoa Bay, The dive sites are both inside the bay and to the west of Cape Recife, in and area known as the Wildside, which is more exposed to south-westerly swells, but is deeper and has more extensive reefs.

KwaZulu-Natal is a province on the east coast, between Mozambique to the north and the Eastern Cape to the south.

Umkomaas and Scottburgh

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Main topic: Diving Aliwal Shoal

In 1849, after a ship, the Aliwal, nearly collided with an uncharted reef, its captain reported the position of this reef that later became known as the Aliwal Shoal. It is about 60 km south of Durban. The closest towns are -30.20130.79424 Umkomaas and -30.2833330.7525 Scottburgh, both of which provide extensive tourist facilities, including for scuba divers.

The shoal is a fossilised sand dune lying roughly parallel to the coast, about 5 km from the shore. It comprises a narrow northern part, the crown, some 250 m wide, becoming about 800 m wide and finally with a wider landward ridge to the south, greater than 2 km in width. The crown varies in depth from about 6 m at the Northern Pinnacles to around 30 m on the seaward side. The mean depth of the crown area is 12.5 m. The southern wider area includes several protrusions that reach from a depth of some 30 m to around 15 m (e.g. Howard's Castle, Landers Reef). In the crown area, many dive sites, (e.g. Raggie Cave and Chunnel) have a large amount of uneven topography with small caves, ledges and swimthroughs rich in sea life, both in fish and invertebrates.

The shoal region has a subtropical climate with mean monthly air temperatures ranging from 17.0°C (Jul) to 23.9°C (Feb). The sea temperatures tend to be somewhat warmer, due to the warm, tropical, southward-flowing Agulhas current, resulting in 21-26°C throughout the year.

Main topic: Diving inland in South Africa

The inland dive sites are spread over a large area and include:

• -25.931130.71058 Badgat: — a flooded asbestos mine near Mbombela in Mpumalanga province.
• -26.508928.06569 Bass Lake: — A disused dolomite quarry near Meyerton south of Johannesburg in Gauteng province.
• -27.92166723.64166710 Boesmansgat: — A sinkhole, near Kuruman in the Northern Cape province.
• -25.78826.36711 Marico Oog: — a spring between Rustenburg, Zeerust and Lichtenburg, in North West Province
• -25.67720627.75771112 Miracle Waters: — a flooded chromium mine near Brits in the North West Province
• -26.8692526.8692513 Wondergat: — a dolomite sinkhole near Mafikeng in the North West Province

The annual sardine run is a notable event that moves along the south coast as the sardines migrate. Divers and other enthusiasts either follow the run along the coast or meet it as it passes major centres. Huge numbers of sardines are predated on by whales, sharks, dolphin, gamefish, seabirds and of course, humans.

There are recreational diver training schools at most diving destinations in South Africa. Affiliation is with a wide range of internationally recognised Recreational and Technical diving agencies, including PADI, CMAS-ISA, NAUI, IANTD, SSI, SDI/TDI and RAID. Certification from these agencies is generally accepted worldwide. The quality of training available depends more on the instructor and the school than the agency, as is the case in most parts of the world. South Africa has its share of quick turnover and never mind the standards, but also has some really good instructors. Read the standards and make sure you get what you pay for.

South Africa is also a destination of choice for Commercial diver training, as the certification is recognised by the International Diver Recognition Forum, and is much cheaper than in Europe.

There are concerns regarding the impact of sport diving on the reef ecology. Some of these may be legitimate, and study is necessary to test whether this is a real problem. The number of dives in the region has increased significantly over the years, but there is no reliable numerical data available. The number of sites has also increased, so the frequency of dives at most sites will not have increased proportionately.

Recreational divers are generally in favour of conservation, and as they are not permitted to collect or capture any marine life on Scuba in South African waters, generally do not consider themselves to make a significant environmental impact. There is evidence that some damage is done by contact with reef organisms and by disturbing the sediment. The question then, is how significant is this impact in comparison with other pressures?

The South African National Spatial Biodiversity Assessment 2004 Technical Report indicates that "Non-Extractive Recreational Activities" has been identified as a potential threat to marine biodiversity. This category is ranked 7th of the nine categories and includes Diver based activities such as snorkelling, scuba diving and cage diving to view sharks, as one of five subcategories. The identification and ranking of the potential threats was made by "Summed Expert Ratings", a procedure similar to the scoring method for competitive dancing, gymnastics and similar sports.

The authors claim that it has been established that scuba diving and associated activities can cause significant damage to coral communities by destructive contact (anchoring and diver damage), resuspension of sediments and by hand-to-coral contact. They also mention that coral reefs in South Africa are confined to the Greater St Lucia Wetland Park where anchoring or mooring is prohibited, and that current research has indicated that the coral reefs of this region have not experienced serious diver damage.

They also state that most divers cause very little damage to coral reefs although underwater photographers have been identified as a group that causes more damage to reefs than other users.

Their findings also show that the prevalence of predominantly soft corals on South African reefs makes them fairly resilient to diver damage.

Unfortunately the government department of Marine and Coastal Management has made use of this report and surveys on tropical coral reefs to support an effort to make money out of recreational diving on the reefs in all marine protected areas by imposing a permit system as a recreational diver tax. No surveys of temperate reefs can be produced to justify their claims that divers are a threat to the reef ecology, and it seems unlikely that their interference will benefit either the ecology or the diving industry.

At the time the policy was perceived as a thinly disguised attempt to tax what department political appointees appeared to see as a wealthy but politically powerless minority group. However, there was an immediate reaction by the recreational diving industry and the recreational divers who use the affected areas, to the effect that the proposed permit fees were reduced significantly and the industry is more united than it had ever been before. The non-profit organisation Underwater Africa was formed to represent the recreational divers and recreational diving industry and it has fought tirelessly for the rights of its constituency.

Even in its restricted scope the permit system may have damaged the industry, as a number of dive charter operators have subsequently gone out of business, and the main effect appears to be that divers are harassed by officials of MCM while poaching has increased.

There is no evidence that the permit system has achieved any of its stated aims of providing finance for improved conservation in the MPAs. It is questionable whether it even covers the cost of its own administration, and may be merely an employment opportunity for the otherwise unemployable.

Marine and Coastal Management has (2010) gone through a period of major change as the government split its responsibilities between two departments. Fisheries have been transferred to the Department of Agriculture Forestry and Fisheries (DAFF), and conservation has gone to Department of Environmental Affairs (DEA). Internal turf wars at upper levels appear to be continuing to reduce effectiveness, and the working staff seem to have difficulty getting their jobs done. The most notorious of the previous management appear to have been transferred sideways rather than fired. So it goes.

Marine Protected Areas

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Marine Protected Areas of the Cape Peninsula and False Bay

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Tsitsikamma Marine Protected Area

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Marine protected areas of Port Elizabeth

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Marine protected areas of Aliwal Shoal

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Marine protected areas of Sodwana and northern KZN

A large number of the most popular dive sites of South Africa are in proclaimed Marine Protected Areas, and a permit is required to scuba dive in any MPA. The permits are valid for a year and are available at some branches of the Post Office. Temporary permits, valid for a month, are usually available at dive shops or from dive boat operators who operate in MPAs. The permits are not expensive, but the requirement to have them present at the site is an annoyance, as they are paper, and the printing on them states that the original permit, the invoice, and the holder's original identity document or passport must be produced on demand.

The department has officially specified that notarised copies are acceptable, but this information does not appear to have been passed on to their staff, who are frequently reported as insisting on the originals, and their generally uncouth and threatening attitude is notorious. The same personnel are seldom available to take action when complaints of poaching are made. It is not clear whether this is because the poachers tend to react violently to interference, while recreational divers have a long history of non-violence, or because they are on the take.

There have been accusations of corruption against personnel of MCM, which have not been cleared up, and the fact that a large part of the department's income derives from marine products confiscated from poachers is seen by many to be a conflict of interests, as this income would dry up if poaching was stopped.

It should probably be mentioned that the policies of MCM regarding recreational diving restrictions are in many cases not supported by members of their research staff, though obviously these are private opinions.

As of 2010 MCM has been split between the Department of Agriculture, Forestry and Fisheries (DAFF) and the Department of Environmental Affairs (DEA). The situation has not improved after the split, and it is not clear, apparently even to the personnel of the two departments, who is responsible for what in the field of marine conservation. Some political officials appear to be attempting to gain short term popularity by trying to open reserves to artisanal fishers, in complete contradiction of the conservation policies, and enforcement is no better than before. Poaching goes on unabated, and divers are still harassed because it is much safer than attempting to apprehend the poachers, who tend to be armed and dangerous.

DAFF and DEA were recombined, with Agriculture split out, to form DEFF, the Department of the Environment, Forestry and Fisheries, which seems to be working a bit better. More MPAs have been proclaimed, mostly offshore in the Exclusive Economic Zone, but it is not clear if and how they are being protected.

A lot of ships have been wrecked on South Africa's long, rugged and dangerous coastline during the last 500 years. Due to its strategic location on the historical trade route between Europe and the East, at least 2700 vessels are known to have sunk, grounded, been wrecked, abandoned or scuttled in South African waters.

Wrecks and their associated artifacts can be impressive and interesting sites for recreational scuba diving and underwater photography. The diversity of wrecks around the South African coast offers divers a wide range of sites to visit and explore. At the same time, historical wrecks are a unique, fragile and non-renewable cultural heritage resource of great archaeological value. We all have a responsibility to conserve this heritage for future generations.

Divers are free to visit most wreck sites, but should remember that they are privileged to have access to these sites, which are an important part of our collective cultural heritage.

The complex and delicate nature of wreck sites requires that divers are especially careful when visiting them. To preserve them for future generations to enjoy and learn from, it is important that you appreciate the importance of wrecks, dive responsibly and treat shipwrecks with care and respect.

Wrecks are also important habitats for marine life. Avoid damaging wrecks by carelessly touching them with your hands, knees or fins. The disturbance of protective coverings of sand, plant growth or the products of corrosion that have formed on wrecks can greatly increase the rate at which a wreck and its contents decay. This reduces the wreck's value as an historical resource and dive site and divers should avoid doing anything that will disturb the delicate equilibrium of a wreck site.

Anchoring into wrecks can cause severe damage to artifacts and the structure of the wreck. If you need to anchor, ensure that you do so well off the wreck. Remember that a wreck site is non-renewable, and won't regenerate like a damaged reef. Dive with care and leave the wreck as you found it.

These vary by region. Refer to the regional dive guide.

• Compressed breathing air quality from commercial suppliers is required by law to comply with SANS 10019. This is of an internationally acceptable standard. The filling station is obliged to keep a record of the results of air quality testing on site and show them to a user on request. This requirement is not usually stringently enforced, nevertheless, where there is competition for business, the air is usually good.
• Compressor Operators who fill cylinders are legally required to be competent in terms of South African National Standard SANS 10019, but there is no requirement for certification, and this requirement is not often enforced. The CMAS-ISA Compressor operator certificate is generally considered within the recreational diving industry to be a sufficient indication of competence, though not a necessary one.
• Compressed breathing gas fills are required by SANS 458:2005 table A.1(b) item 4 to be within 5% of the nominal fill pressure corrected to 20°C, and it is illegal to fill a cylinder to a higher pressure than a developed pressure equivalent to the working pressure stamped on the cylinder at 20°C, corrected to actual temperature when filled. The pressure must be checked before you leave the filling station, or it will be virtually impossible to prove deficiency. All filling stations are required to provide an accurate and calibrated pressure gauge if requested. In practice the gauges are seldom recently calibrated.
• Scuba cylinder colour coding is prescribed by SANS 10019 to be canary yellow with a french grey shoulder. Nitrox and trimix cylinders should have been cleaned for oxygen service before first use with mixed gases, and be labeled for the service. Technically a commercial filling station may not fill a cylinder that is not the right colour or is not in date for visual inspection and hydrostatic tests. Privately owned, filled and used cylinders are not restricted in the same way.
• Nitrox fills will normally be mixed on demand, and the customer is expected to personally test or observe the test for oxygen content and sign for it. After that it is your own business what you do with it. You may be asked to show Nitrox certification, but that is up to the seller, and is not required by law. Cylinders to be filled with Nitrox are required by law to have a label showing the composition of the contents, but the specifications for the label are so mind bogglingly incompetent that filling stations may require more rationally useful labels than legally required. Most stations will accept cylinders with the old style labels, as they at least provide adequate information. Composition is usually written on masking tape with a waterproof marker and stuck to the shoulder of the cylinder. This may or may not be legal, as the authorised experts are not keen to admit either way, and it is the standard procedure.
• Cylinders to be filled with Trimix are also required to be labelled with the contents. The size and position of the label is specified, but it is not required to actually be visible, and it is a position commonly covered by tank bands if the cylinders are twinned. Additional labels which can actually be seen are not forbidden, and may be used.
• Cylinders dedicated to 100% oxygen for breathing must be black with a white shoulder, but Nitrox cylinders may be filled with 99% Oxygen, and Nitrox mixes only need to be analysed to the nearest 1% accuracy. If you have a Nitrox cylinder filled with Oxygen for decompression gas, label it as 99% and it will be legal.
• Medical oxygen specifically intended for surface first aid purposes should be carried in the official black cylinder with white shoulder. Most have a pin index valve, but this is not a legal requirement, and a bullnose fitting as is used on bulk cylinders, or a scuba pillar valve may also be used, depending on the regulator available. As it is not a legal requirement to carry medical oxygen on a dive boat, it is also not a requirement to use any specific type of regulator. The regulators marketed by DAN are popular, and possibly the best for purpose, as they allow 100% on demand for conscious users and can also supply free-flow to a medical mask for unconscious users. Other types may be diving regulators which will only supply a demand regulator, and some older free-flow systems intended for general first aid purposes.
• The law requires that cylinders which are to be filled with gas mixtures containing more than 23% oxygen must be cleaned before the first fill with such gas mixture. Filling stations often require that there is an Oxygen clean label on the cylinder if it is to be filled by partial pressure blending, but this is not a legal requirement.
• Oxygen is carried by most dive charter boats, and this is considered the industry standard, though not required by law.
• First aid kits are required by law to be carried on boats.
• Skippers of dive boats are required by law to be certified for the category of vessel they operate, and to have a diving endorsement to the certificate. This certificate must be carried on the boat, so you can expect to be shown it if you ask at a reasonable time. If the boat is launched through the surf, the skipper's certificate must also be endorsed for surf launching. Unfortunately the certificate does not guarantee competence, but most of the skippers get good or get out.
• Skippers are also required to be trained in basic first aid, but this is very basic and does not include decompression illness.
• Dive boats are obliged by law to carry safety equipment and pass a safety inspection every year. This is shown by a certificate and a decal on the boat.
• Vessels used for any commercial purpose must be licensed or registered in terms of the Merchant Shipping Act.
  • Small craft licensing: You can recognise and identify a licensed vessel by the license number it must display on the sides. The number consists of a prefix identifying the licensing authority, followed by a number identifying the vessel, and any applicable category letters.
    • South African Maritime Safety Authority (SAMSA) uses DT plus a letter identifying the port of origin. DTC is Cape Town. The number may be followed by a class letter indicating the waters the boat is licensed and equipped to operate in.
    • South African Deep Sea Angling Association (SADSAA) uses club identification prefixes.
    • South African Sailing (SAS) uses SA for sailing vessels and ZA for motor vessels
    • South African Small Craft Association (SASCA) uses U followed by the category and then the number.
    • South African Institute for Skippers (SAIS) uses A
    • South African Police Service (SAPS) uses SAPS

• Malaria is endemic to some regions in the north east of the country. For divers this is mainly northern KwaZulu-Natal.
• Bilharzia is also endemic to some regions on the east coast, but only affects fresh water, so is not generally a problem to divers.
• HIV is widespread. However it is not really a particular problem for recreational divers.

All major diving centres in South Africa have recreational diver training schools. Most of the major international diver certification agencies are represented in South Africa. See also the regional dive guides for local details.

These include:

• PADI
• NAUI
• CMAS
• SSI
• IANTD
• TDI/SDI
• RAID

Technical diver training is available at the major centres such as Cape Town, Durban and Johannesburg, and at Badgat, also marketed as Komati Springs, where the site is suitable for deep and cave diving throughout the year. Rebreather training is available, but only where there is an instructor certified to train the specific equipment. This varies from time to time.

(Including scientific diving and public safety diving)

The South African Department of Employment and Labour certifications in Commercial Diving are recognised by the International Diver Recognition and Certification Forum. Divers holding certification that is recognised by the IDRCF may legally work as commercial divers in countries represented on the forum, provided that other visa and work permit conditions are complied with.

There is not a great deal of commercial diving work in South Africa, and the pay is not very good by world standards, but the training is cheaper than in most other countries on the IDRCF, and as a result South Africa has become a training destination for foreign commercial divers. Learner divers from Europe have commented that the cost of training at home covers the training costs, medical examination, travel and living expenses and enough change for an additional vacation in South Africa. South African commercial diver training is also popular with learner divers from many countries where there is no officially sanctioned commercial diver training system, and the certification, though there is no guarantee of employment, allows the holder to apply for lucrative work in the international offshore petrochemical industry.

A reasonable ability to communicate in English is a prerequisite, and medical fitness to dive must be verified by a medical practitioner registered as a Diving Medical Practitioner with the South African Department of Employment and Labour. Foreign medical certificates of fitness to dive are not recognised for commercial diving.