Also known by some as Bangsak Wreck, Boonsung Wreck is a very popular place, both for divers to visit and for a vast amount of marine life to call home. The visibility is usually not great near the surface, but the abundance of fish and invertebrates more than makes up for this. The location is ideal for easy day trips from Khao Lak as well as for the final dive of Similan Islands liveaboard cruises. The depth is suitable for Open Water Divers and for those who want a shallower dive at the end of a diving safari.
Boonsung Wreck is not a shipwreck. It’s an old dredging vessel that had been used for decades mining tin. There are various rumours about how it ended up where it is. These include its owners deciding the easiest and cheapest thing to do with it after it had ceased to become worthwhile was just sink it, and others claim that it sank by accident after a toilet became flooded. Anyway, after it sank parts of it were too near the surface. So the Royal Thai Navy deliberately destroyed parts of the wreck to make it safer for passing ships, and this caused it to spread out across the sandy sea bed. It was further broken up by the devastating 2004 Asian tsunami.
Even trained wreck divers should not try to penetrate this wreck though. Swimming around inside is very risky for several reasons. These include small chambers with no room to turn around, the high chance of silt being stirred up and reducing visibility, and the dozens of camouflaged Scorpionfish and thousands of sharp edges all over it. In recent years the locals have placed some concrete statues around the edges, including dolphins and even a porcelain toilet.
The location of Boonsung Wreck
The location of Boonsung Wreck makes it easily accessible for day trip boats from Tab Lamu Pier and from Bangsak Beach in Khao Lak. Even a two-dive daytrip boat doesn’t need to be a fast one, and you will be back well in time for dinner. Small groups often dive Boonsung from a long-tail boat. Only several kilometres from the mainland, from the boat you can easily see Khao Lak and the mountains behind.
Sea conditions are usually calm at the surface during the high-season months of November to April. Under the surface, the visibility is always a topic of conversation and it can range from great to dangerously low. In general, the visibility is approximately 10 metres, but when less than this you can still enjoy a great dive for the full planned duration. The bottom is a mixture of sand and silt, and is very flat in all directions. Currents are very rarely anything to talk about. They vary from nothing at all to very mild.
The depth of Boonsung Wreck
The depth of Boonsung Wreck is pretty consistent around the site, and only affected by the tides. On average, the sandy bottom is about 19 metres deep, and the wreck’s shallowest point approximately 14 metres. This means that Open Water Divers are able to enjoy all of it, and it’s even possible to do the final two dives of your Open Water Course at Boonsung. Also, those who are finishing a Similan liveaboard cruise at Boonsung can ensure that they don’t go too deep, and absorb unnecessary amounts of nitrogen. Saying this though, because there’s nothing shallower than 14 metres, it’s impossible to do a multi-level dive here, so you need to keep an eye on NDL (no decompression limits) which is the main number displayed on your dive computer.
Things to be aware of
Things to be aware of at Boonsung Wreck include venomous fish, such as the Scorpionfish & Lionfish, and the sharp edges of broken or decayed metal of the structure. A good diver can control buoyancy and knows not to touch anything. Therefore, a good diver shouldn’t need to need to worry too much, and there are never strong currents here, so controlling your position in the water is easy. However, divers without good buoyancy skills or those who need to hold on to the structure in order to get the best photo or video footage need to be very careful. This includes which parts of Boonsung Wreck are safe to touch with your hand as well as minding where other parts of your body are, such as your knees if you dive in a shorty wetsuit. The numerous Honeycomb Moray Eels have extremely sharp teeth and retractable jaws, but they will always hide from divers rather than bite.
The marine life at Boonsung Wreck
The marine life at Boonsung Wreck is always the highlight. Very occasionally a Whale Shark pays a visit, but these sightings are extremely rare. To be honest, they probably pass by more often than divers are aware due to everyone looking at the resident marine life and the low visibility. What you can be absolutely guaranteed to see here is plenty of nudibranchs, Pufferfish & Porcupinefish, Lionfish & Scorpionfish, Honeycomb Moray Eels, and huge shoals of juvenile species including Snapper, Barracuda, Fusilier and more. You will soon forget about any low visibility after being immersed in a shoal of fish, or distracted by the thousands of creatures that call this home.
Everyone has their own idea of which species are the stars of Boonsung Wreck. Some divers prefer the huge schools of juvenile fish that use Boonsung as a nursery before they mature and swim out into the ocean. Others like the brave, and sometimes in-your-face, Pufferfish and Porcupinefish. Honeycomb Moray Eels are quite rare out at sea around the Similan Islands, where you can see plenty of Giant and White-Eyed Morays. But here at Boonsung you will only see Honeycomb Morays, and plenty of them. Nudibranch lovers will not be disappointed with diving at Boonsung Wreck, either. There are thousands of individuals all over, and many different species & genera. Venomous fish are also abundant here, with lots of Scorpionfish and Lionfish guaranteed to be seen on every dive.