Happily for Koh Samui, beaches line about 90% of its coastline, one reason for its global fame as a top beach holiday destination. These beaches include everything from the four kilometres of unbroken sand on Chaweng to sandy coves of just 50 metres secreted among the huge granite boulders on the southeast coast. Several beaches, like Lamai, Chaweng and Bophut, are wall-to-wall with hotels and resorts while others have barely a bungalow for each kilometre of coconut fringed sand, as on the south and west coasts.
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All beaches are public land in Thailand, we should note, from the highest high tide mark down, and open to all citizens. Resorts like to claim theirs is a 'private' beach, and while it may be effectively true, it is based only on their monopolizing all access to a beach because outsiders cannot cross their land. Anyone, however, may come ashore on any beach in Thailand by boat – even if hotel security guards try to tell you otherwise.
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The beauty of Samui's beaches is almost legendary. Many of the images that sell Thailand to the world show crystal waters calmly lapping white sands, with coconuts swaying above and green mountains towering behind. That's Samui through and through. Visitors to Thailand are often disappointed when they reach the beaches along the mainland coast, and find they have no resemblance to the stunning beauties in the travel promos. They had probably seen a Samui beach, or a beach on another of Thailand's many resort islands.
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The sand on Samui's beaches varies radically, from the super fine powder on Chaweng Beach to the mini-stones of Lamai; ground up granite particles. But even this sand, coarse enough for a back scratch when you lie on it, makes a beautiful beach. However, Samui's beaches have lots of sand, and be it white, yellowish or granular, and it's mostly very clean.
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The water clarity too, is usually excellent through the calm, high season months. The Gulf of Thailand is shallow, and especially so close to Koh Samui. When storms and waves blow up the local seas are soon stirred and the clarity lost. November to January is the northeast monsoon season in Samui, do remember, and the water is mostly rough and murky then.
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Shade on the beach – another critical issue in a place as hot as Samui – is provided in most places by big beach trees that have been preserved or planted long ago. However, there are some more barren, hot zones where the resorts have cut the trees in favour pools and hotel facilities right up against the sand. Here Guests are often forced indoors during the hottest hours of the day, even during the 'winter' months. When checking hotel photos, remember the importance of thick, natural shade close to the beach – not all resort developers do.
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Beach massage comes in an avalanche on Samui beaches, with freelance masseuse ladies found under shady trees on all of the major beaches, politely beckoning passers-by. As the number of masseuse hopefuls has risen over the years, prices have remained low, below $10 per hour.
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Beach vendors are found in small numbers on the busier beaches, with the largest concentration on Chaweng. Those selling fruit and local food like som-tum, roast chicken and sticky rice do a booming business, with their services clearly appreciated by the many customers. Those selling clothing, sarongs and souvenirs are less appreciated, and sometimes more intrusive. In general, though, Thai beach vendors are polite.
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Samui's many unseen beaches; one of the most potent forces behind this island's global fame is the number of beaches that few people ever see. Many little beach gems are secreted away in remote bays that mainstream tourists neither see nor even suspect exist. Romantic hideaways lie hidden in picture-perfect coves crowded by huge granite boulders. And in many cases one simply cannot get to the beach without checking into a high-class resort, or hiring a boat. See Samui's 7 perfect, unseen beaches .
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Koh Samui and its neighbouring islands of Phangan and Koh Tao are far enough south in the Gulf of Thailand to get away from the ever-murky water trapped in the enclosed, top sector of the gulf. There, several rivers dump the sediment of about 30 million careless people into the sea. When swimming around these southern islands you won't run into the constant barrage of hard-to-see plastic bags that annoys swimmers at Pattaya and nearby beach destinations.
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The waters of the Gulf of Thailand average only 60 metres in depth, though around Samui things get even shallower. While the clarity is generally good to excellent in calm periods, it is easily stirred by both monsoon storms and the strong spring tides that rush back and forth each 14 days. Meeting ideal conditions for diving and snorkelling is thus a game of chance, and checking tide charts.
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During the northeast monsoon from November to January things are constantly stirred up, so forget diving and snorkelling during these months. The mini high season that Samui often serves up in July and August can be good diving months.
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Diving is popular in Samui, though divers are generally taken to sites in open water well away from the shore. Dedicated divers mostly head to Koh Tao, the top dive destination on this side of Thailand. Some dive companies use fast boats to run the 55 kilometres to Koh Tao in good weather. However, nowhere on the Gulf side of the country ever sees the extraordinary water clarity that is common along the islands off Thailand's Andaman Coast during the 6-month calm season.
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Snorkelling around the fringes of Samui is quite nice when water clarity is good, particularly along the southeast coast – but it's no longer exciting. Colourful, live coral reefs that enchant snorkelers are limited to little patches, though the big granite boulders do create some interesting topography. Few fish as big as a kilogramme can be seen. Sadly, the waters around this island have been so thoroughly fished out that few of Samui's original fishermen can now make a living from the sea, and there is not a lot of ocean life to entertain snorkelers either.
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Strangely, Koh Samui often experiences only two tides each 24 hours instead of the normal four. It can affect holidays here for those who are intent on using the water a lot. It means that you may experience low tide through the whole day, without enough water to swim, or high tide with most of the beach submerged throughout the day.
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This effect of halving the number of tides is a phenomena exclusive to enclosed bodies of water like deep bays or gulfs, and is known around the world. When both incoming and outgoing water has to pass the same channel, the receding flow cancels or reduces the incoming one. See more about the strange tides of the Gulf of Thailand here.
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In general, expect high tides through the day in November to March, and low water all day from May to October. However, if swimming and the depth of water in front of your resort is critical to your holiday, check for a beach without the offshore reef, like Maenam, or the southern ends of Chaweng and Lamai. Then, to choose the right month with high water during the day, consult the tide charts online. Or leave your chances to the moon.
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The fringing offshore reefs that trap sand and make so many tropical beaches shallow are also common on Samui, exacerbating the problems of shallow water caused by freak tides. Luckily, a number of beaches on the east and north coast are free of these annoying reefs, including south Chaweng and Lamai, Maenam and Bophut. Virtually all of the west and south coasts are enclosed by such a reef, and have such shallow water that swimming is difficult or impossible at all but high tide.
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by John Everingham