Scuba Diving the Cape Peninsula and False Bay: A Guide to Cape Town's Waters

The Cape Peninsula from space: the Atlantic seaboard on the left, False Bay on the right. (Photo: NASA, Public domain)

The waters around Cape Town, South Africa, hold over 300 named dive sites with recorded positions, all within a day trip by road from anywhere in the city, which is a lot for any single destination. This guide is for divers who are already qualified, whether local or visiting. Conditions change fast here, so treat it as a starting point and check everything on the day.

The lie of the land and sea

The Cape Peninsula is a narrow, mountainous finger of land, at most 11 km wide and just over 50 km long, running south from the city to Cape Point. Table Mountain (1,085 m) forms its backbone. Its western shore faces the open Atlantic; its eastern shore faces False Bay, a roughly square bay about 30 km across, open to the ocean on its south side, shallow and gently sloping, with one true island, Seal Island. Locals call the west side "the Atlantic" and the east side "False Bay", or the Simon's Town side, and so does this guide.

Cape Point also divides two marine worlds: the cold-temperate waters to the west and the warmer Agulhas waters to the east, and the change in marine life between the two coasts is plain to see. Underwater, the reefs mostly look like the shore above them, because they were shaped as dry land during the ice ages. Granite makes big boulders, overhangs, holes and swim-throughs; sandstone makes ridges, ledges and small crevices.

Weather, water and when to go

The south-western Cape has a Mediterranean climate: dry summers and wet winters, unlike the rest of South Africa. The two coasts take turns.

Upwelling has a catch: the cold water is rich in nutrients, and a few days of sun can turn it into a plankton bloom, a red tide, that cuts visibility within hours. Tides are weak and currents rarely a problem, except around Rocky Bank and Bellows Rock at the mouth of False Bay. Forecast sites for wind and swell help, but reading the conditions takes practice; until you have the feel of it, ask local divers.

Winter diving in False Bay: the ride out may be wet. (Photo: Peter Southwood, CC BY-SA 4.0)

What lives here

The kelp forests are the signature habitat. Sea bamboo grows up to the surface in shallow water, the shorter split-fan kelp lives deeper, and near Robben Island a third, bladder kelp, joins them: one of the few places in the world where three kinds of kelp grow together. Sandy bottoms look bare but hold animals found nowhere else on the reef.

Kelp forest on an inshore reef. (Photo: Peter Southwood, CC BY-SA 3.0)

Many of the fish and invertebrates are found only in South Africa, and while they are not as bright as tropical fish, many are colourful. Look out for:

• Cape fur seals, which come to look at divers. If they are relaxed, there are probably no great white sharks hunting nearby.
• Sevengill sharks (cowsharks) at a few sites, and catsharks almost everywhere.
• Shoals of yellowtail now and then, and on lucky days sunfish, whales or dolphins.
• Southern right whales, which visit False Bay in large numbers every year, though a diver rarely meets one.

Cape fur seals come to look at divers. (Photo: Peter Southwood, CC BY-SA 3.0)

A sevengill cowshark. (Photo: Peter Southwood, CC BY-SA 3.0)

Wrecks. The Cape of Storms sits on one of the world's great shipping routes, with a rough coast and few shelters, so there are many wrecks, from 3 or 4 m deep to more than 65 m. Many have never been found, and many are broken up or buried, but several can be dived and now act as artificial reefs. In South African law a wreck becomes a protected historical wreck 60 years after it sank.

Divers on the wreck of the Cape Matapan in Table Bay. (Photo: Peter Southwood, CC BY-SA 3.0)

What to bring

Most sites are shallow enough for air and ordinary recreational gear: a full wetsuit of at least 5 mm with hood, boots and gloves; cylinder, regulator and gauge; buoyancy compensator; mask, snorkel and fins; ditchable weights; and a dive computer or tables. Rental cylinders usually have DIN valves with plug adaptors for yoke regulators, so check before booking. Some tips:

• A dry suit is recommended for most Atlantic dives, and anywhere deeper than about 20 m in water colder than 13°C.
• Open-heel fins and hard-soled boots suit the rough walk to most shore entries.
• Carry a delayed surface marker buoy (DSMB) on boat dives; a towed buoy snags endlessly in thick kelp.
• A compass helps you swim back under the kelp or away from boats.
• Nitrox is widely available; rebreathers, sidemount and full-face masks are uncommon but workable if arranged in advance.

A backward-roll entry from a rigid inflatable dive boat. (Photo: Peter Southwood, CC BY-SA 4.0)

Permits and respect

Most sites lie in the Table Mountain National Park Marine Protected Area or the Robben Island MPA, and scuba diving in any MPA needs a permit: annual ones from some Post Office branches, and temporary ones, valid for a month, from dive shops and boat operators. Night dives need notice to SANParks and are not allowed between 23:00 and 04:00.

On the reef, keep your buoyancy, keep your fins off the bottom and touch nothing fragile, especially the false corals, sea fans and anemones. If you need a handhold in the surge, use the lower part of the kelp stipes or the tough red bait sea squirts. Do not move animals for a photograph, and do not collect anything without a permit.

Staying safe

• Weather. A south-easter can rise from a calm, clear day to near gale force while you are under water, so plan your exit. On a hot Atlantic day the air can pass 30°C while the water is below 10°C: overheating and hypothermia on the same outing.
• Shore dives. Getting in and out is often harder than the dive: a scramble over boulders, sometimes from a car park 50 m above the sea. Know your exit, and how it looks from the water, and tell someone ashore your plan.
• Boats. Tow a bright buoy with a dive flag at busy sites near Miller's Point, and do not trust every skipper to keep clear.
• Great white sharks use False Bay, especially the west side from Muizenberg to Simon's Town. Spotters' records show more sightings in summer, in water of 16 to 20°C, and from the waning moon to new moon.
• Stings and spines. Bluebottles (Portuguese men o' war), electric rays, sea urchins and bristle worms: gloves and a wetsuit help, and nothing here is likely to be serious.
• On land. Theft from parked cars is the biggest danger. In the southern peninsula, baboons open unlocked car doors in search of food; lock up and never feed them.

The one-fin electric ray can give an unwary diver a startling shock. (Photo: Peter Southwood, CC BY-SA 3.0)

In an emergency, call a paramedic service such as Netcare 911 (082 911) or Metro Rescue (10177), and the DAN Southern Africa 24-hour hotline (+27 82 810-6010, toll-free 0800 020 111), which will make further arrangements for its members. If you must take a casualty yourself, go to the Claremont Hospital Emergency Unit, whose staff know diving accidents. Send the casualty's dive computer along, with someone from the group who can answer questions. The National Sea Rescue Institute is on +27 21 449-3500.

Sources

• "Diving the Cape Peninsula and False Bay" from Wikivoyage, by its contributors, under CC BY-SA 4.0. Changed: rewritten in hubnx's own words and condensed from the full guide; the lists of dive shops, schools, charters, slipways and individual dive sites left out (the original links them); each photo under its own licence, credited in its caption. This page is shared under CC BY-SA 4.0.