Aliwal Shoal scuba diving

About Aliwal Shoal

Aliwal Shoal lies a few kilometres off the coast at Umkomaas, south of Durban in KwaZulu-Natal. It is not a coral reef but a ridge of ancient sand dunes that turned to rock long ago and was later drowned by the rising sea. Over time, corals, sponges and seaweeds have colonised the rock, and its gullies, caves, overhangs and pinnacles now shelter an enormous amount of life.

The shoal takes its name from the ship Aliwal, which nearly ran aground on it in 1849. Today it is protected as the Aliwal Shoal Marine Protected Area, with zones that limit fishing and set rules for diving. Like other South African marine protected areas, diving here needs a permit, which dive centres can explain.

Aliwal Shoal is easy to reach from Durban, which makes it one of the most dived sites in South Africa and a natural first stop on a KwaZulu-Natal dive trip. It suits a wide range of divers on calm days, though current, swell and visibility vary a lot from day to day.

The raggies: Aliwal's winter visitors

Aliwal Shoal is best known for raggedtooth sharks, called "raggies" locally and known elsewhere as sand tiger or grey nurse sharks. Each year, roughly from June to November, raggies gather on the shoal, where they are thought to mate before the pregnant females move north to warmer water. They look fierce, with long ragged teeth showing, but they are calm, slow-moving sharks that tend to hover in the gullies and caves.

Seeing a dozen or more raggies resting in a cave is one of South Africa's classic dives. The rules are simple: stay calm, keep low, do not block their way out of a gully, and do not touch them. Your guide will show you how to position yourself so the sharks swim past you naturally.

Aliwal Shoal dive sites

1. Cathedral

   Raggie season highlight · Amphitheatre

   A large, roofless amphitheatre in the reef with an arch-like opening, and the most famous raggie site on the shoal. In season, raggies circle slowly inside it. Divers wait at the edges rather than swimming in among the sharks.

2. Raggie Cave

   Raggies · Overhangs

   An overhang where raggies like to rest during the winter. Out of season it is still a good reef dive, with soft corals, fish and the chance of turtles.

3. The pinnacles and gullies

   Reef · Range of depths

   Much of the shoal is a maze of pinnacles, ledges and sandy gullies. Look for moray eels, rays, turtles, big shoals of reef fish and the many small creatures living on the rock: nudibranchs, shrimps and octopus.

4. Baited shark dives

   Offshore · Blacktips and tiger sharks

   Away from the reef, operators run baited dives in open water, where blacktip sharks are the regular visitors and tiger sharks may join in the warmer months. These dives are run to strict briefings and divers stay together in the water column. Read more in our guide to shark diving in South Africa.

Wrecks near the shoal

Two shipwrecks lie close to Aliwal Shoal, and many dive trips combine a reef dive with a wreck dive. The Produce, a cargo ship, sank near the shoal in 1974, and the Nebo, a steamship, sank in 1884. Both are now covered in marine life and home to big fish, and both are deeper than the shallower parts of the shoal, so they suit divers with some experience. Our wreck diving in South Africa page has more on them and on the other wrecks around the country.

Conditions and the launch

Boats launch from the Umkomaas river mouth and run out through the surf, much like at Sodwana Bay. Hold on, follow the skipper's instructions and keep your gear secured. Dives are usually done as a group from the boat, often as drift dives with a surface marker buoy, and the skipper follows the group.

The water is warm for most of the year thanks to the Agulhas Current, and a 5 mm wetsuit suits most divers. Visibility can be excellent on good days and limited after rain or rough weather, when the rivers bring sediment into the sea. The current on the shoal can be strong, and the swell can make the shallower parts surgy, so dive centres pick sites day by day.

When to go

For raggedtooth sharks, plan for roughly June to November. For tiger sharks on the baited dives, the warmer summer months are the usual season. Humpback whales pass along this coast in winter and spring, and dolphins are seen all year. If you want to add the Sardine Run, it usually reaches the KwaZulu-Natal coast in mid-winter in the years when it comes this far north: see our Sardine Run diving guide.

Aliwal Shoal combines well with Protea Banks, a little further south, for divers who want deeper, more advanced shark diving.